0530756 COVER SHEET FOR PROPOSAL TO THE NATIONAL SCIENCE FOUNDATION NSF 05-527 03/11/05

COVER SHEET FOR PROPOSAL TO THE NATIONAL SCIENCE FOUNDATION
PROGRAM ANNOUNCEMENT/SOLICITATION NO./CLOSING DATE/if not in response to a program announcement/solicitation enter NSF 04-23
NSF 05-527
NSF PROPOSAL NUMBER
03/11/05
FOR CONSIDERATION BY NSF ORGANIZATION UNIT(S)
FOR NSF USE ONLY
0530756
(Indicate the most specific unit known, i.e. program, division, etc.)
CMS - NEES RESEARCH
DATE RECEIVED NUMBER OF COPIES DIVISION ASSIGNED FUND CODE DUNS#
FILE LOCATION
(Data Universal Numbering System)
009214214
EMPLOYER IDENTIFICATION NUMBER (EIN) OR
TAXPAYER IDENTIFICATION NUMBER (TIN)
IS THIS PROPOSAL BEING SUBMITTED TO ANOTHER FEDERAL
AGENCY?
YES
NO
IF YES, LIST ACRONYM(S)
SHOW PREVIOUS AWARD NO. IF THIS IS
A RENEWAL
AN ACCOMPLISHMENT-BASED RENEWAL
941156365
NAME OF ORGANIZATION TO WHICH AWARD SHOULD BE MADE
ADDRESS OF AWARDEE ORGANIZATION, INCLUDING 9 DIGIT ZIP CODE
Stanford University
651 Serra Street
Stanford, CA. 943054125
Stanford University
AWARDEE ORGANIZATION CODE (IF KNOWN)
0013052000
NAME OF PERFORMING ORGANIZATION, IF DIFFERENT FROM ABOVE
ADDRESS OF PERFORMING ORGANIZATION, IF DIFFERENT, INCLUDING 9 DIGIT ZIP CODE
PERFORMING ORGANIZATION CODE (IF KNOWN)
IS AWARDEE ORGANIZATION (Check All That Apply)
(See GPG II.C For Definitions)
TITLE OF PROPOSED PROJECT
MINORITY BUSINESS
IF THIS IS A PRELIMINARY PROPOSAL
WOMAN-OWNED BUSINESS THEN CHECK HERE
NEESR-SG: Controlled Rocking of Steel-Framed Buildings with
Replaceable Energy Dissipating Fuses
REQUESTED AMOUNT
PROPOSED DURATION (1-60 MONTHS)
1,600,000
$
SMALL BUSINESS
FOR-PROFIT ORGANIZATION
48
REQUESTED STARTING DATE
10/01/05
months
SHOW RELATED PRELIMINARY PROPOSAL NO.
IF APPLICABLE
CHECK APPROPRIATE BOX(ES) IF THIS PROPOSAL INCLUDES ANY OF THE ITEMS LISTED BELOW
BEGINNING INVESTIGATOR (GPG I.A)
HUMAN SUBJECTS (GPG II.D.6)
DISCLOSURE OF LOBBYING ACTIVITIES (GPG II.C)
Exemption Subsection
PROPRIETARY & PRIVILEGED INFORMATION (GPG I.B, II.C.1.d)
INTERNATIONAL COOPERATIVE ACTIVITIES: COUNTRY/COUNTRIES INVOLVED
or IRB App. Date
HISTORIC PLACES (GPG II.C.2.j)
(GPG II.C.2.j)
SMALL GRANT FOR EXPLOR. RESEARCH (SGER) (GPG II.D.1)
VERTEBRATE ANIMALS (GPG II.D.5) IACUC App. Date
PI/PD DEPARTMENT
PI/PD POSTAL ADDRESS
Civil & Environmental Engineering
PI/PD FAX NUMBER
240 Terman Engineering Center
Stanford, CA 943054020
United States
650-723-7514
NAMES (TYPED)
HIGH RESOLUTION GRAPHICS/OTHER GRAPHICS WHERE EXACT COLOR
REPRESENTATION IS REQUIRED FOR PROPER INTERPRETATION (GPG I.E.1)
High Degree
Yr of Degree
Telephone Number
Electronic Mail Address
ph.d
1988
650-723-0453
ggd@stanford.edu
PhD
1997
650-723-4125
billington@stanford.edu
PhD
1988
612-626-8225
hajjar@struc.ce.umn.edu
PI/PD NAME
Gregory G Deierlein
CO-PI/PD
Sarah L Billington
CO-PI/PD
Jerome F Hajjar
CO-PI/PD
CO-PI/PD
Page 1 of 2
Electronic Signature
B. PROJECT SUMMARY
Our built infrastructure needs to be made less vulnerable and easier to repair after a major earthquake. Of
particular concern are certain conventional systems, such as concentrically braced steel frame buildings,
which are quite prevalent and designed with excessive reliance on inelastic deformations – often more
than they can provide. In the most extreme cases, this can result in a serious life safety risk and, in many
other cases, can result in damage that is very expensive to repair. Performance-based earthquake
engineering provides an objective means both to assess the performance of conventional systems and to
design innovative new seismic resisting systems that can meet the economic and safety needs of modern
society.
The proposed research aims to develop a new structural building system that employs rocking action and
replaceable structural fuses to provide safe and cost effective resistance to earthquakes. The system
combines desirable aspects of conventional steel-braced framing (or equally valid, of reinforced concrete
walls) with two alternative and complementary fuse concepts – shear panel fuses and axial column fuses.
Materials that will be investigated for implementing the fuses are high-performance fiber reinforced
cementitious composites and ductile buckling restrained steel components. Guided by performance-based
capacity design principles, the fuses are easily replaceable and can be tuned to provide optimal
performance. Through controlled rocking of the structure, concerns about damage to foundations and
primary structural elements are avoided.
The research will take full advantage of complementary features of the NEES MAST facility and Japan’s
E-Defense shaking table. With one of the key objectives being to validate the proposed seismic system
for reliable use in engineering practice, the E-Defense facility provides the unique capabilities to perform
dynamic shake table tests of a nearly full-scale building prototype.
Intellectual Merit: The proposed research will lead to seminal advances in concepts, techniques, and
models for the design of controlled rocking mechanisms for steel building systems using replaceable
energy dissipating fuses. The fuses utilize novel materials and components, including combinations of
high-performance fiber reinforced cementitious composite shear panels fuses, low-yield steel shear panel
fuses, and buckling-restrained axial column fuses. This combined computational and experimental
research investigates both component and complete system response, synthesizing the results through a
methodology for performance-based design that directly assesses life safety and life-cycle economic
factors. The proposed concept emphasizes damage prevention to foundations and other structural
elements that are difficult to repair; inelastic energy dissipation in structural fuses that are easy to replace;
story drift control so that nonstructural damage is reduced; and sufficient safety against collapse. The
research involves an international NEES/E-Defense collaboration, leveraging U.S. and Japanese facilities
and resources. Large-scale experiments will be carried out to validate the systems, coupled with the
development of new computational models on the NEESgrid for the novel materials involved. The
project team is committed to fully utilizing the simulation, visualization, and collaboration tools of the
NEESgrid to dramatically increase the rate of data assimilation, comprehension, and learning, within the
context of a distributed international project.
Broader Impact: The proposed research is expected to have a major impact on engineering practice,
providing the opportunity to design and construct damage tolerant, easy-to-repair, and cost effective
structural systems. A detailed data sharing and archiving plan for these complex large-scale tests and
parametric simulations will advance the state-of-art in model-based simulation and data archiving. The
project leadership team is comprised of co-PI's who are diverse in gender, age, and specialty, and who are
geographically well distributed at a non-NEES equipment site and a NEES equipment site. The project
has a natural engineering education component through the research participation of graduate and
undergraduate students. Diversity initiatives for high school, undergraduate, and graduate students will
leverage associations with outreach programs at two major universities and the education program of an
NSF-funded EERC.
TABLE OF CONTENTS
For font size and page formatting specifications, see GPG section II.C.
Total No. of
Pages
Page No.*
(Optional)*
Cover Sheet for Proposal to the National Science Foundation
Project Summary
(not to exceed 1 page)
1
Table of Contents
1
Project Description (Including Results from Prior
NSF Support) (not to exceed 15 pages) (Exceed only if allowed by a
specific program announcement/solicitation or if approved in
advance by the appropriate NSF Assistant Director or designee)
20
References Cited
5
Biographical Sketches
(Not to exceed 2 pages each)
Budget
10
16
(Plus up to 3 pages of budget justification)
Current and Pending Support
6
Facilities, Equipment and Other Resources
3
Special Information/Supplementary Documentation
2
Appendix (List below. )
(Include only if allowed by a specific program announcement/
solicitation or if approved in advance by the appropriate NSF
Assistant Director or designee)
Appendix Items:
*Proposers may select any numbering mechanism for the proposal. The entire proposal however, must be paginated.
Complete both columns only if the proposal is numbered consecutively.
D. PROJECT DESCRIPTION
D.1 - Project Participants
Table 1. Project Participants
Name
and
Title
Gregory G.
Deierlein
Professor
Affiliation
Stanford
University
Principal
Investigator
Sarah
Billington
Asst. Prof.
Stanford
University
Co-Principal
Investigator
Jerome F.
Hajjar,
Professor
University
of
Minnesota
Expertise
Role in Project
Research management,
performance-based earthquake
engineering, nonlinear analysis,
design of steel and composite
steel-concrete structures,
development of building code
provisions.
Design and behavior of
structural concrete and
HPFRCC materials and
systems, computational
modeling of cementitious
composites.
Large-scale structural testing ;
nonlinear structural analysis
and design; performance-based
earthquake engineering.
Co-Principal
Investigator
Helmut
Krawinkler
Professor
Stanford
University
Performance-based earthquake
engineering assessment and
design, experimental and
analytical simulations.
Building
Research
Institute
(Japan)
Seismic design and behavior of
steel structures, large-scale
testing and shake table
simulations, Japanese building
code standards
Other Senior
Personnel
Mitsumasa
Midorikawa
Research
Coordinator
of Building
Technology
Other Senior
Personnel
D-1
Project coordination (PI);
schematic design and planning of
building systems; planning and
design of shake table test at EDefense, coordination of
education and outreach activities.
Time
Commitment
(mos./year)
2-2-2-2
Planning, design, modeling and
testing of HPFRCC shear
dissipation panels, collaboration
on system test at MAST and EDefense; summer REU advising.
1-1-1-0.5
Planning, design and execution of
medium- and large-scale quasistatic system tests; data archiving
and curation to NEES repository;
project website; education and
outreach activities.
Design and seismic performance
assessment of rocking wall
systems, building system studies,
coordination of wall-frame system
test at E-Defense and large-scale
test at UMN.
Project coordination of Japanese
collaborators, development of
braced-frame rocking systems
following Japanese construction
practice, planning and design of
shake table test at E-Defense.
0.75-0.750.75-0.75
0.5-0.50.5-0.5
1-1-1-1
D.2 - Utilization of NEES Equipment Resources, E-Defense and Stanford Experimental Facilities
Major testing will be conducted at the NEES Multi-Axial Subassemblage (MAST) Large-Scale
Testing System at the University of Minnesota (UMN) and the E-Defense shake table in Japan. In
addition, material and small component testing will be conducted in the structural engineering laboratory
at Stanford University. Section I (Facilities, Equip., and Other Resources) includes further details on the
capabilities at these facilities and Table 2 shows the planned occupation at each site.
Table 2. Scheduling for NEES and Major Equipment Site Usage (* = 1 month)
Site
10/1/05 – 9/30/06
10/1/06 – 9/30/07
***
UMN Mast
***
***
***
***
***
***
10/1/08 – 9/30/09
***
***
E-Defense
Stanford
10/1/07 – 9/30/08
***
***
***
UMN MAST Laboratory: The MAST system will be used to conduct the three-dimensional large-scale
quasi-static cyclic tests of the controlled rocking structural systems investigated in this research. These
tests will characterize the progressive damage and inelastic response of the structure and will validate the
qualities of the system. With the MAST system, six degree-of-freedom control technology is employed
to manipulate a stiff steel crosshead that can statically apply combined axial load, shear, overturning
moments, and torsion. The system can accommodate structural subassemblages as large as 6.1 m (20 ft.)
square in plan and 7.6 m (25 ft.) high. The MAST facility has unique capabilities to apply large gravity
loads to the test specimen combined with unified overturning moments and shears that may be applied in
a cohesive, coupled fashion to separate bays of the test specimen, thus being able to apply precise loads
and displacements to the optimal locations in this frame system to investigate the controlled rocking
motions proposed in this research.
E-Defense Shake Table: The large 15 x 20 m shake table at the E-Defense facility in Japan will be used
to conduct dynamic tests of a large (near full-scale) building system with a hybrid rocking bracedmoment frame system with structural fuses. The E-Defense shake table is required to accommodate the
large-scale testing which is critical to investigate the energy dissipating fuse mechanisms and the hybrid
braced-moment frame system at a realistic scale. The large scale is necessary to accurately simulate the
behavior, which is necessary both from a scientific point of view (accurate representation and
understanding of the behavior) and to demonstrate the validity of the new rocking fuse system to
engineers and other stakeholders. Apart from its large size, the E-Defense facility provides other benefits.
The lab is developing an inertial system to apply gravity loads and seismic mass in multi-story building
models. This inertial frame will simplify the shake table test setup and make the test more economical.
Another benefit is that this proposed project will leverage financial and intellectual resources of a
companion Japanese project that will be funded by the Japanese government (see supporting letter from
Dr. Nakashima, Director of E-Defense).
STANFORD Structural Engineering and Materials Lab: The Structural Engineering and Materials
Lab at Stanford University has a strong floor and several loading frames that can be used for
development testing of the shear panel fuses. The laboratory is equipped with loading actuators,
measurement transducers, and data acquisition systems. The lab also houses equipment for fabrication,
curing and testing of high performance fiber reinforced cementitious composite (HPFRCC) materials.
For materials testing there are two MTS testing machines; one is an 89 kN (tension/compression), fatigue
rated machine with hydraulic grips, the second is a 245 kN (tension/compression), fatigue rated machine
with a 1 x 2 meter loading table. This facility has access to the high-speed Internet-2 and can be used for
internet-based collaboration (e.g. telepresence) and NEES data archiving for this project.
D-2
D.3 - Strategic Research Vision
Introduction: Recent advancements in performance (or consequence) based earthquake engineering have
provided objective means for assessing the performance of conventional structural systems, but equally or
more importantly, they provide effective techniques for developing and assessing new innovations that
will make our future stock of buildings less vulnerable to earthquake damage and easier to repair after a
seismic event. In conventional seismic systems reliance is placed on the primary structural components
deforming inelastically and thereby dissipating the energy imparted to a structure by a major seismic
event. Very often, insufficient attention is paid in conventional designs to balancing initial costs with life
cycle considerations, which include estimation of direct losses due to structural and nonstructural damage,
downtime losses, and repair of structural damage, in addition to life safety considerations.
The work proposed here addresses all these issues in the contexts of developing and testing innovative
fused rocking (pivoting) systems that limit the extent of structural damage and provide for quick,
efficient, and cost effective repair. The concept of structural fuses is not new, but it has not been
sufficiently developed because of past inability to provide an objective assessment of their costs and
benefits. Now the means for an objective assessment exist, and the emphasis of research needs to shift to
the development of cost-effective design improvements.
There are two ways to approach future system design. One is to improve incrementally on conventional
systems. The second, which is the approach taken in this proposal, is to devise new systems that provide
higher performance with greater resiliency. Let us use braced steel frames as an example. They are
known to be vulnerable because of questionable post-buckling behavior of braces (which may fracture)
and because of great difficulties in designing brace connections and column base plates that can sustain
significant inelastic deformations (see Section D.4.1). Improvement to conventional braced frames will
help, but a more effective design solution is to avoid all the conditions that create undesirable behavior of
braces and connections. This is where the fuse concept comes to bear, as its implementation intends to
prevent undesirable behavioral modes. The fuse concept has several objectives, including the following:
• Provide story drift control so that drift sensitive nonstructural damage is reduced
• Provide floor acceleration control so that acceleration sensitive nonstructural and content damage is
reduced (e.g., in a hospital or a museum)
• Provide controlled structural damage that can cost effectively be repaired after a major earthquake
• Prevent damage to foundations and other elements that are difficult to repair, and
• Provide sufficient safety against collapse.
Proposed Braced-Frame Fuse System:
As illustrated in Fig. 1, the proposed research focus is on the development of a
seismic force resisting system that combines desirable aspects of conventional
steel-braced framing (or equally valid, of
reinforced concrete walls) with two alternative and complementary fuse concepts – shear panel fuses and axial
column fuses. The framing configurations shown are two examples of possible
Figure 1 – Pivoting Braced Frame (a) single bent with shear
variants that can be envisioned with this
dissipating panels, (b) dual bent with shear dissipating panels and
system. The underlying concept of the axial dissipating strut
system utilizes controlled rocking
(pivoting) and a capacity design approach to concentrate inelastic deformations in the fuse components.
The configuration of Fig. 1a demonstrates the application of a shear panel fuse, where energy is dissipated
D-3
through the large shear strains developed across the shear panel between the braced frames. For a given
story drift, the magnitude of shear strain energy dissipated in the panel is proportional to the ratio of the
dimensions of the braced panel to the shear panel, i.e., the dimensions B/A shown in Fig. 1a. Thus, by
altering the geometry, one can achieve large amplifications in shear deformations, whereby large amounts
of energy can be dissipated at low drifts. Ideally, the shear panels should have a large elastic stiffness, a
well defined yield point, and large energy dissipation capacity. Two materials that will be investigated
for the shear panels are high-performance fiber reinforced cementitious composites (HPFRCC) and lowyield steel plates. The panels are connected to the frame with bolts (or dowels) and are designed for easy
access and replacement. This is in contrast to conventional systems, such as eccentrically braced steel
frames or coupled shear walls, where the shear links are integral with the structural system and difficult to
repair once they are damaged. Likewise, the inelastic hinge regions of moment frames are integral to the
structural frame and difficult to repair.
The configuration shown in Fig. 1b demonstrates the use of axial column fuses, which can either be
designed to work on their own or in combination with the shear dissipation panels. The axial deformations of a fuse are related to the bay width by the ratio of bracing panel width to story height (A/H). One
way to implement the axial column fuses is through the use of buckling-restrained columns (BRCs),
similar in concept to buckling-restrained braces (BRBs) that have been successfully introduced into
design practice over the past ten years [1]. Like their BRB counterparts, the BRCs would be designed to
dissipate energy through large inelastic deformations of a steel core, which is prevented from buckling by
some type of housing (often a steel tube filled with concrete). Another candidate for the axial column fuse
is a yielding base plate, such as Midorikawa et al. [2] have studied. The configuration of Fig. 1b
demonstrates where it may be advantageous to employ both axial column and shear panel fuses, so as to
improve response or redundancy of the systems.
For optimal building performance, the fused
bracing systems (Fig. 1) are intended for use with
a parallel system that provides an elastic restoring
force. As suggested by the framing plan in Fig. 2,
we envision that the parallel system to be a flexible moment resisting steel frame. The combination of the stiff fused braced frame and the flexible frame offers several advantages over
conventional systems or either system acting
alone. By balancing the strength, stiffness, and
inelastic deformation characteristics of the two
systems, the goal is for the moment frame to
remain essentially elastic under the design
earthquake, thereby providing a restoring force
that will reduce (or even eliminate) residual drifts.
This is in contrast to conventional dual systems,
where both systems are expected to deform
inelastically and their interaction is unknown.
After large earthquakes, when the fuses may be
damaged, the moment frame will stabilize the
system while the fuses are removed and replaced.
Figure 2 – Schematic framing plan for hybrid system:
energy dissipating braced frames with elastic moment
frames
Performance-Based Design: Recent advances in performance (or consequence) based assessment and
design [3-7] have made it possible to assess the benefits of various design enhancement techniques objectively by incorporating increases in up-front construction costs and projected benefits in terms of reduced
losses (direct losses and downtime losses) and increased (or collapse) safety.
D-4
Illustrated in Fig. 3 is the
Hazard
Structural System Domain
method that will be employed
Domain
to assess the value of the proCollapse
Hazard Curves
Mean IM-EDP Curves
posed braced system with fuses
Fragility Curves
for Design Alternatives
for Design
for Design
Alternatives
[8]. This method will address
E ( EDP | IM & NC )
Alternatives
the issues of losses in nonγ=0.2
γ=0.1
T =0.9 sec. γ=0.3
λ(IM)
P(C | IM )
γ=0.2
γ=0.1
T =1.8 sec. γ=0.3
structural drift sensitive subSa(T )/g
Sa(T )/g
Sa(T )/g
Sa(T )/g
systems (NSDSS), nonstructural acceleration sensitive
subsystems (NSASS), the
T =0.9sec.
structural subsystem (SS), and
T =1.8sec.
the issue of losses due to
collapse.
Provided that
intensity measure (IM) hazard
P(C|Sa(T )/g)
IDRavg.
FAavg.
µavg.
curves and
mean loss– λ(Sa(T )/g)
engineering demand parameter
NSDSS
NSASS
SS
(EDP)
curves
of
the
Expected
subsystems are known (or can
Total $Loss
(in
millions)
be estimated), this figure
illustrates
how
various
structural systems can be
EDP=Avg. of max.
EDP=Avg. of max.
EDP=Avg. of max.
story drift ratios,
evaluated using the mean IMfloor accelerations, stories ductilities,
IDR
FA (g)
µ
EDP curves of structural
E ( $ Loss | EDP & NC )
E ( $ Loss | C )
systems without and with fuses.
$Loss Curves
$Loss Value
As alternative configurations
(No Collapse)
(Collapse)
are tested, the properties of the
structural system can be tuned
$Loss Domain
such that the system’s IM-EDP
Figure 3. Illustration of conceptual performance-based design process
curve shows explicitly how
much can be gained by
utilizing the fuses, measured in terms of loss reduction and improved collapse safety. Use of the fuses
will come at a cost whose benefits can be assessed from the reduction in losses.
1
1
1
1
1
1
2.0
2.0
2.0
2.0
1.5
1.5
1.5
1.5
1.0
1.0
1.0
1.0
0.5
0.5
0.5
0.5
1
1
0.0 0.005 0.01 0.015 0.02 0.025
Expected Subsystem
$Loss ( in millions)
10/50
2/50
0. 5
0.0
0.5
1.0
1.5
2.0
2.0
4.0
6.0
0%
50%
100%
1
12.0
12.0
12.0
10.0
10.0
10.0
8.0
8.0
8.0
6.0
6.0
6.0
4.0
4.0
4.0
2.0
2.0
2.0
0.0
0.0 0.005 0.01 0.015 0.02 0.025
avg.
0.0
0.5
1.0
avg.
1.5
2.0
Expected Total $Loss at
Collapse ( in millions)
50/50
1
2.0
4.0
6.0
12.0
10.0
8.0
6.0
4.0
2.0
0.0
avg.
These concepts for performance-based design are an extension of performance-assessment tools, which
have been developed through research supported by the NSF (e.g., the Pacific Earthquake Engineering
Research Center, http://peer.berkeley.edu, the Mid-America Earthquake Center, http://mae.ce.uiuc.edu),
FEMA (e.g., FEMA 273 and ATC 58), and other organizations.
NEES/E-Defense Collaboration: The proposed research will be an international collaboration between
US and Japanese participants and will utilize the NEES MAST and the E-Defense facilities. With one of
the key objectives being to validate the proposed system for use in engineering practice, the E-Defense
facility provides the unique capabilities to perform dynamic shake table tests of a nearly full-scale
building prototype. The research topic is of mutual interest to the Japanese researchers and industry. A
team under the leadership of Dr. Midorikawa (Research Coordinator of Building Technology at the
Japanese Building Research Institute) has been identified; and, as indicated in the attached letter from Dr.
Nakashima (Director of E-Defense), funding for Japanese collaborators has been secured. The co-PI’s
have a long history of collaboration with Japanese researchers, and over the course of developing this
proposal we have corresponded extensively with Dr. Nakashima and Dr. Midorikawa. They both are
enthusiastic about collaborating with us on this project, and we have included Midorikawa as a co-leader
to direct the proposed collaborative testing at the E-Defense facility. Should this proposed be funded, we
also expect that the Japanese will become involved in the proposed testing at the NEES MAST facility
and send visiting researchers to the U.S.
D-5
D.4 - Background and Literature Review
D.4.1 Seismic Design and Performance of Steel Braced Frame Systems
The performance of braced frames in earthquakes has been a
major concern for researchers and engineers for many years.
Until 1985, there was no specific requirement in the UBC to
design bracing connections for anything but a 25% increase in
the code seismic design forces. Since then, code requirements
have tightened and the present requirements are to “design the
connection for the maximum force, indicated by analysis, that
can be transferred to the brace by the system” [9]. But recent
earthquakes and laboratory experimental studies have shown
that this general requirement does not safeguard sufficiently
against post-buckling fracture of braces or against brittle failure
modes in brace-to-brace, brace-to-column/beam, and columnto-base plate connections. Undesirable behavior has recently
been demonstrated in tests of a steel braced frame that was
designed according to current seismic design standards (AISC
2002). As shown in Fig. 4 [10], not only did the inelastic
deformations concentrate in one story, but they further
localized in local buckles that led to premature fracture under
cyclic loading. Other studies have raised similar concerns
Figure 4. Brace Buckling Failure Observed in Lab
[11,12] as have many local and global failures of braced frame
structures in recent earthquakes [13, 14], see Fig. 5. The brittle connection failures have a multitude of
sources, including fracture of net sections, impact loads due to straightening of slender members, out-ofplane buckling of gusset plates, fracture at weldments due to gusset plate buckling, or fracture in very
thick base plates such as those of the Oviatt Library in the 1994 Northridge earthquake [13, 15].
Clearly much research has yet to be done to evaluate and quantify each failure mode and its
consequences, and building code detailing provisions should be revised considerably, to safeguard against
all failure modes that may significantly affect the safety of
braced frame structures. Moreover, it is very likely that postelastic behavior in braces and their connections in an
earthquake will require extensive and costly repair actions.
For these reasons it should be a most attractive alternative to
avoid all these undesirable failure modes by designing braces
and connections such that they respond elastically, and calling
upon controlled energy dissipation modes in which the
dissipative mechanisms are predictable, reliable, and easily
replaceable. This is the objective of the proposed work.
D.4.2 Controlled Rocking (Pivoting) Seismic Systems
Figure 5. Collapse of a Braced Frame, Kobe Earthquake, 1995
One of the two energy dissipating fuse mechanisms to be investigated is that associated with controlled
rocking (or pivoting) at the base of a braced frame. In concept, this mechanism can be represented by
adding a rotational base spring whose yield moment and elastic and post-elastic stiffness provide the
mechanism for controlling the force transfer into the structure. If the spring yield moment is zero, the
consequence is unrestrained pivoting. Analytical studies (see Section D.4.6) will identify what spring
properties best serve the objective of achieving desirable performance. Knowing the desired
characteristics, the challenge is to achieve these through energy dissipating pivoting mechanisms that are
(a) cost effective, (b) reliable, and (c) easily replaceable after a damaging event.
D-6
The pivot point itself may consist of a mechanical
(true) pivot, or more likely a compact region of
steel that is designed to undergo cyclic rotations
without damage. Most of the energy dissipation
is expected to come from devices inserted
between the chords of the braced frame (or wall)
and the foundation. Potentially attractive devices
are buckling restrained columns and other steel
elements that dissipate energy effectively in
bending or shear (or in friction in case of friction
damping devices). As one example Midorikawa
[2] has conducted shake table tests of a rocking
braced frame that employs a flexural fuse in the
base plate (Fig. 6). Tipping Mar Associates, a Bay Figure 6. Rocking base fuse by Midorikawa et al. [2].
Area Consulting Firm, is proposing to use a
similar system, with plate bending in steel angle sections to dissipate energy at the base of a rocking
braced frame and prestressed cables along the chord members as a self-centering mechanism [personal
communication]. There are many options for cost effective and replaceable energy dissipation devices at
the base of pivoting braced frames (or walls) that can and will be explored in this work.
The concept of improving performance through either controlled or even uncontrolled rocking is not new.
Already Housner looked into the potential benefits of rocking [16]. Meek [17] conducted analytical
investigations into the behavior of a flexible single-degree-of-freedom system (inverted pendulum) on an
unbonded rigid foundation mat. He concluded that a reduction in base shear, upwards of 20%, is evident
during tipping when compared to a bonded system. Shaking table tests performed at the University of
California, Berkeley on a 9-story steel frame without tension tie-downs [18] experimentally demonstrated
that there is a distinct reduction in system base shear during transient uplift. They recorded a 30%
reduction in base shear and corresponding overturning moment in the test frame due to rocking. Other
important fundamental work on modeling rocking and/or foundation uplift is published in [19, 20]. An
interesting and related concept of a sliding concave foundation was recently introduced in [21]. Ajab et al.
[22] performed an analytical study in which rocking of wall-frame structures was augmented with
supplemental tendon systems to enhance damping. These and other studies (such as those performed on
rocking of bridge piers [e.g., 23, 24]) will form the background on which the proposed project will build.
The literature review has disclosed that in appropriate configurations rocking indeed is a beneficial
mechanism that can be taken advantage of to improve seismic performance. The review has also
disclosed that the proposed mechanisms, which rely on shear dissipating panels made of HPFRCCs and
on axial dissipation mechanisms, have not been a subject of thorough study. The potential benefits of
such mechanisms are illustrated in Section D4.6.
D.4.3 Buckling Restrained Braces
As mentioned previously with respect to Fig. 1b, components similar to buckling restrained braces BRBs
are envisioned as an attractive way to implement the axial column fuses in the lowest story of a braced
frame. Buckling restrained braces consist of a steel core (e.g., a plate or tube) surrounded by steel tubes,
concrete confined by an external tube, or other arrangements that enable the steel core to yield symmetrically in tension or compression, in particular without buckling while in compression. The great
advantage of these elements is that they have already found widespread application in the US, Japan and
Taiwan, that they are commercially available, and that much experimental research has been performed
on their cyclic behavior and their application as bracing elements. Recent research on buckling-restrained
braced frames provides an excellent foundation for understanding strength, stiffness, and ductility of these
components. Many component and system studies of BRB frames have been conducted [e.g., 25-35] and
have shown that systems designed with braces such as are currently available can provide high levels of
D-7
ductility and can be designed for large drifts. These
components show stable, symmetric hysteretic response, as
illustrated in Fig. 7 from a typical experimental test.
D.4.4 High Performance Fiber Reinforced Cementitious
Composites
High Performance Fiber-Reinforced Cementitious Composites (HPFRCC) are an example of a damage-tolerant, energy
dissipating material that that will be investigated for use as
shear panels between the proposed rocking braced frames.
The HPFRCC we will investigate exhibits fine, multiple Figure 7. Cyclic response of a BRB [25]
cracking and a strain hardening response in direct tension. The material is micromechanically designed to
achieve this response using a small volume fraction of polymeric fibers, typically less than 2% by volume
[36].When HPFRCC is reinforced with steel, the two materials exhibit compatible deformation where
both reach several percent strain when yielding [37]. As a result, bond stresses are low and typical failures due to bond splitting and spalling are not observed. Additionally, overall strength is increased
(because the HPFRCC unlike concrete, can carry tension to large strains) and larger portions of the steel
can yield than is the case with traditional reinforced concrete, allowing for larger hysteretic energy
dissipation. HPFRCC materials have been investigated recently for several applications for seismic
resistance [38-44]. In all cases, a consistent finding has been the extreme damage-tolerance of the
material, in that the multiple fine cracks close almost completely upon unloading, after large cyclic lateral
displacements (e.g. 10% drift) and no spalling is observed in compression. HPFRCC can be precast or
cast-in-place in large volumes.
Most closely related to this proposal is the research on shear behavior [45-47] and infill panel applications
[40] using HPFRCC materials combined with mild steel reinforcement. Shear stress vs. strain results
from Ohno shear beam tests [48] are shown in Fig. 8. Only the reinforced concrete specimen contained
mild steel. The HPFRCC systems (mix 1 with metal fibers and mix 2 with polymeric fibers) performed
very well in comparison with the concrete and traditional FRC specimens despite having no conventional
shear reinforcement. These results demonstrate how different HPFRCC mix designs can be used to give
different properties whether it be higher strength or higher ductility. Furthermore, a recent study on infill
panels subjected to a lateral shear load demonstrated that reinforced HPFRCC could result in over 60%
larger hysteretic energy dissipation than a reinforced concrete panel with the same reinforcement ratio
(Fig. 9) [40]. Finally, connection details of these infill systems have verified the ability of the material to
be connected using pre-tensioned bolts and withstand cyclic loading [46, 49]. This establishes HPFRCC
panels as replaceable components on a story-by-story basis. However, alternative details such as using
Applied Load (kN)
60
Actuator
HPFRCC
mix 1
HPFRCC
Panel
Reinforced
concrete
HPFRCC
mix 2
40
20
0
-2.50%
-1.50%
-0.50%
0.50%
1.50%
-20
Plain
concrete
-40
HPFRCC-1
HPFRCC-2
Reinf. Concrete
-60
Figure 8 Shear stress vs. strain cement-based
materials [45]
Figure 9 Hysteretic response of infill panels [40]
D-8
2.50%
Drift (%)
low strength steel on either side of the HPFRCC panel to form a sandwich system may prove attractive.
Prior research by Hossain and Wright [50] has shown ductile monotonic response of composite infill wall
systems that use corrugated metal deck with infill concrete. Zhao and Astaneh [51] have proposed a steel
plate shear wall system with reinforced concrete attached to one side of the steel plate with bolts to help
mitigate shear buckling of the plate. The system showed excellent ductile response. Based upon
alternative details such as those seen in prior research, in this work, the most cost-effective, ductile, and
replaceable use of HPFRCC shear panels will be explored.
D.4.5 Nonlinear Modeling and Simulation of Seismic Response
Nonlinear analyses that accurately simulate the inelastic response of structures are essential for
performance-based earthquake engineering assessment and design, particularly with regard to simulating
the initiation of damage up to the onset of collapse. Our plan is to utilize OpenSees [52] which is well
suited to this research and has recently been adopted as a computational simulation component of NEESgrid. OpenSees provides a versatile object-oriented framework, with modeling capabilities to capture
large-deformation stiffness and strength degrading response of structures subjected to large earthquake
ground motions [53-54]. Matlab prototyping tools [55] available through NEESgrid provide the ability to
conveniently develop and test new models, such as will be required to simulate the HPFRCC shear panel
fuses. In previous research, the PI and his students have implemented element and material models to
simulate inelastic behavior and large deformation response in beam-columns and beam-column joints [5758]. Other researchers have applied OpenSees to (a) exercise emerging performance-based assessment
techniques to evaluate the performance of real buildings and bridges [59], (b) simulate the response of a
pseudo-dynamic test of a full-scale composite frame [60], and (c) simulate shake table tests of a steel
frame with fracturing connections [61].
D.4.6 Performance of Pivoting Braced Frame with Energy Dissipation
The concepts of performance assessment for tuning the properties of braced frames with fuses to produce
desirable behavior have been illustrated in Fig. 3. Using braces with base fuses as part of a braced frame
– moment frame hybrid system, the following parameters can be varied to tune the behavior: moment
frame stiffness and base shear strength, braced frame stiffness and strength assuming a fixed base, and
pivoting rotational stiffness of the braced frame. It is the combination of these six global system
parameters that will govern the quality of performance.
The following simple example, a study of four structures subjected to a suite of 40 ground motions scaled
to a high earthquake hazard, illustrates the effect of these variables. The base structure, designated as
“frame” in Fig. 10, is a 9-story moment-resisting frame with a first mode period of 1.8 sec. and a base
shear capacity of 0.1W (details of the frame are presented in [63]). This frame is the common element in
three other dual moment-braced frame systems. In all three combinations the braced frame stiffness is
equal to twice the moment frame stiffness. The variant called “fixed” in Fig. 10 has an infinitely strong
braced frame with a fixed base. The other two cases have a rotational spring at the base. The case called
“pin” has zero rotational stiffness, whereas the cased called “fuse” has a rotational stiffness comparable
to the frame and a yield moment equal to 0.13WH. The first mode periods of the four configurations are
1.8 sec. for frame and pin, 1.26 sec. for fuse, and 0.96 sec. for fixed.
The median roof drift ratios of the four configurations are 1.5%, 1.4%, 1.1%, and 0.9%, respectively for
frame, pin, fuse and fixed. Median values of pertinent response parameters are compared in Figs. 10a-c.
The story drift profiles clearly show the benefit of stiffening with braced frames. The benefit of adding
an energy dissipating fuse, is comparable to that achieved by adding a fixed base braced frame, except in
the lower stories. Hinging the braced frame at the base, pin, forces the interstory drift to be rather
uniform over the height, with the maximum interstory drift of about 60% of that of the moment frame.
Consistent patterns are observed also for story shear force and overturning moment demands. Both are
increased by the addition of braced frames, by a very large amount for the fixed base braced frame, and
by much smaller amounts by letting the base pivot freely or providing an energy dissipating fuse.
D-9
The conclusion suggested by this study is that the widespread use of fixed base braced frames (or shear
walls) is an often ineffective way of achieving desirable performance. It requires the transfer of large
shear forces and overturning moments within the structure and to the foundation, and is not very effective
in reducing interstory drifts, with the possible exception of lower stories. This makes a strong case for
exploring hinged braced frames (or shear walls) and braced frames with energy dissipating fuses. In the
analytical studies, this will be investigated, with the objective being to provide definitive design
guidelines for selecting relative strength and stiffness properties to achieve desired performance with in
the context of the performance criteria illustrated in Fig. 3. Additional performance objectives are ease of
replacement of damaged fuses, and self-centering of the structural system due to the elastic strain energy
stored in the moment frame after removal of damaged fuses.
z/H
z/H
z/H
Maximum Interstory Drift Profiles (Medians)
The shear force and over1
turning moment demands
on the fixed base braced
(a)
0.75
frame are large and imply
the need for “inelastic” de0.5
fixed
sign and reliance on large
frame
0.25
“ductility” capacity. This
fuse
pin
raises challenges associated
frame
fixed
pin;
0
with inelastic response of
0
0.005
0.01
0.015
0.02
0.025
0.03
fuse
Max IDR
conventional braced frames,
Maximum Story Shear Profiles (Medians)
Maximum Floor Over Turning Moment Profiles
(Medians)
ranging from undesirable
1
1
post-buckling behavior of
(b)
(c)
0.75
braces, to difficulties in de0.75
signing gusset plates and
0.5
0.5
base plates so that they perframe
fixed
fixed
form well when braces
0.25
0.25
frame
buckle or columns get
fuse
pin
pin fuse
0
overloaded, to great diffi0
0
0.2
0.4
0.6
0.8
1
0
0.1
0.2
0.3
0.4
0.5
0.6
Max Shear / W
culties in repairing foundaMax OTM / WH
tion and structural damage Figure 10. Median Story Responses of 9-story Structures (a) Interstory Drifts, (b)
after a strong earthquake. Story Shears, (c) Story Overturning Moments
All these difficulties can be
mitigated by employing the proposed fuse concepts, which concentrate inelastic behavior in the
replaceable fuses and shelter the braced frame from excessive force demands.
D.5 Objectives and Research Outcomes
Objectives: The primary objective of the proposed research is to advance the state-of-art in the research
and practice of earthquake engineering, through the rigorous performance-based development of an
innovative new concept of pivoting braced systems with energy dissipating fuses. Included within this
overall vision are the following specific objectives:
1. Develop new strategies for the seismic design of building systems that are guided by explicit focus on
the performance objectives of damage control under moderate to large earthquakes and collapse
safety as well as economical repair under major earthquakes.
2. Mitigate earthquake life safety and economic risks to society by the introduction of new structural
systems that utilize new materials and design concepts, based on advanced understanding of structural
response gained through complementary computational and physical simulation.
3. Advance understanding related to the seismic design of hybrid structural systems that combine
inelastic energy dissipating components with elastic restoring systems.
D-10
4. Increase our knowledge and use of high-performance fiber reinforced cementitious composite
materials and low-yield steels for inelastic fuse applications in seismic design.
5. Revitalize earthquake engineering education to emphasize innovative design through the introduction
of new materials and system innovations.
Expected Outcomes and Original Contributions: Our research vision is conceived to provide seminal
advances in earthquake engineering research, education and engineering practice. To successfully impact
all three of these areas, the proposal will explore new concepts, which while quite novel in concept are
readily amenable to implementation with construction materials and methods that have received
comprehensive testing at the component level and initial successful use in other related seismic
applications. Expected outcomes and original contributions include:
1. Development of a new approach to seismic design, suitable for all seismic zones, predicated on
controlled rocking of steel building systems coupled with replaceable energy dissipating fuses.
Through controlled rocking, foundation construction costs associated are reduced, and energy
dissipation occurs in replaceable components that ensure cost-effective and safe structures. These
systems will be developed within the context of a new methodology for performance-based design
that directly addresses the losses to structural as well as non-structural components (e.g., through
control of story drifts and floor accelerations). The final deliverable will synthesize this research
with related past work to propose appropriate design provisions suitable for adoption in practice.
2. Adoption of new materials and components, including HPFRCC, low-yield strength steel, bucklingrestrained columns, and braced-frame pivots, being used to their best advantage for practical
construction applications that help mitigate serious seismic deficiencies in conventional
construction. Both constitutive modeling and large-scale testing of these materials and components
will underpin the validation testing conducted in the NEES facilities and E-Defense.
3. Creation of the NEES/E-Defense initiative, whereby new collaborations will be forged with
Japanese partners at E-Defense with mutual investigation of these systems through integrated
computational and physical simulation, including testing that imposes three-dimensional loading at
both US and Japanese facilities, one through quasi-static cyclic testing, the other through dynamic
shake table testing. These facilities thus enable premier validation of the rocking fuse structural
systems so as to expedite their acceptance into practice.
D.6 Strategic Research Plan
As illustrated in Fig. 11, the research plan is organized around a central spine of activities that integrate
the data and results of the experimental simulations into a coherent systems design approach, culminating
in the development of design implications and recommendations for the new structural framing systems.
The details associated with each task are described later in sub-sections of Section 7.1. Briefly, the main
features of the plan are the following:
Task 1 – Schematic Design of Prototype Systems: Much like in engineering design practice, the research
will begin with a detailed schematic design effort to articulate and quantify the important issues and
parameters for the subsequent experimental and analytical studies. Performance-based design thinking
will guide this effort with consideration given to life-cycle and post-earthquake repair costs.
Task 2- Computational Simulation: As schematic designs are developed, computational models will be
created and tested to simulate the nonlinear seismic response of the structures. Included will be development of models to simulate unique features of the rocking behavior and inelastic fuses, utilizing existing
data on low-yield and BRB steels (from previous research) and HPRFCC panels (obtained from Task 3).
Task 3 – Characterization and Design of HPFRCC Panels: Guided by sizing and performance parameters
identified through the schematic design effort of Task 1, this task will focus on the development of
HPRFCC panels. Data from HPRFCC material and panel testing and computational modeling will
D-11
provide input to characterize the panels
response in the macro-simulations (Task
2) and large-scale validation tests at
MAST (Task 4). A complementary effort (upper right box of Fig. 11) will
synthesize data on BRBs and low-yield
strength steel for energy dissipation.
Task 4 – Development and Large-Scale
Validation of Energy Dissipating Rocking Frames (MAST):
This task
integrates data from the schematic
designs,
computational
simulation
results, HPFRCC shear panel study
(Tasks 1 to 3), low-steel shear panel and
BRC elements, to design and test the
rocking braced frame subassembly and
fuses.
Quasi-static tests will be
conducted at large scale in the MAST
facility, with the primary goals to (a)
Figure 11 – Strategic Research Plan
characterize the shear panel and axial
column fuses, and (b) validate that the system and components (e.g., the brace pivot) work as intended.
Task 5 – Parametric Design and Performance Evaluation of Building Systems: Building upon the schematic designs (of Task 1), the simulation models (Task 2), and the experimental simulation data (Tasks 3
and 4), the parametric design studies pull together the information to conceive and assess a number of
alternative designs. One outcome of this task will be data to plan and design the shake table specimens to
be evaluated at E-Defense (Task 6). The other outcome will be information feeding into the design
implications and recommendations of Task 7.
Task 6: Large-Scale Shake Table Simulation (E-Defense): Data, models and knowledge gained from
Tasks 1-6 will be synthesized and validated through the planning, design and simulation testing of a
large-scale frame on the E-Defense shake table. The frame will be designed as a test bed to permit
simulation of alternative fuse concepts and will be a focal point of US-Japan research collaboration.
Task 7 – Design Implications and Recommendations: The data and information collected and made
accessible through NEES-grid will provide a unique opportunity to accelerate research dissemination on
rocking braced systems with fuses into engineering practice. Design implications and recommendations
will be developed with the participation of professional engineering organizations.
D6.1 Detailed Project Tasks
Task 1: Schematic Performance-Based Design of Prototype Systems -- Input and participation from
engineering practitioners will be applied in the structural design of a variety of prototype building systems
that utilize the fuse details. These will serve as prototypes for computational and physical simulations in
subsequent tasks. The structures will be hybrid systems that involve the energy dissipating braced-frames
acting in combination with moment frames. The plan configurations and number of stories will be varied
as needed to cover the range of likely building applications. Likewise, the merits of alternative braced
frame-fuse configurations will be evaluated.
At least 20 prototype structures will be designed and documented, using a performance-based approach,
for the desired performance targets. For comparison with conventional practice, the resulting designs will
be compared to the strength and stiffness requirements of existing design provisions for standard concentrically and eccentrically braced steel frames. The number of stories will be varied from 2 to 20 to cover
D-12
the full range of configurations for which the proposed rocking braced-frames designs may be
economically feasible and structurally effective. The schematic frame designs will be analyzed using the
nonlinear computational simulation models described under Task 2 in order to provide an initial performance evaluation in terms of the global engineering demand parameters (peak and residual interstory drifts,
peak floor acceleration) and local cumulative damage indices in the fuses.
Task 2: Computational Simulation of Energy Dissipating Rocking Braced Frame Systems -- The
research will make extensive use of nonlinear analysis to simulate the inelastic response of the building
framing systems, including braced frames, moment frames, and the inelastic fuses. Computational
simulations will be conducted using OpenSees (http://opensees.berkeley.edu/), the features of which were
described previously in Section D.4.5. In addition to creating and analyzing building system models
using existing features of OpenSees, this research will include the development, implementation, and
calibration of component models to simulate the inelastic hysteretic properties of the various fuse types.
The fuse mechanisms will be implemented as concentrated multi-degree of freedom springs. Development and implementation of the models will be coordinated and validated through the other tasks dealing
with system and component (braced frame and fuse) performance.
Building system response will be evaluated using nonlinear static (pushover) and inelastic time history
analyses. The latter will be conducted using a strategy termed “incremental dynamic analysis”, where
key parameters of the system response are evaluated under increasing intensities of earthquake ground
motions [62, 64]. The analyses will make use of reliability tools in OpenSees to characterize the sensitivity of the building performance to uncertainties and design variations of the input parameters –
particularly those associated with the relative stiffness of the braced-frame to moment-frame in the elastic
and inelastic response realms.
A
Task 3:
Characterization and Design of
HPFRCC Energy Dissipating Shear Panels -- To
develop the energy-dissipating shear panels for the
large-scale rocking braced frame tests will require
HPFRCC
Shear Panel
two main research tasks: (1) Finite element (FE)
modeling to identify optimal HPFRCC properties
and their combination with steel reinforcement,
and (2) Reduced-scale panel testing to evaluate
panel properties and verify connection detail
A-A
A
behavior. FE modeling will be used to identify the
Figure 12 Shear panel test set-up
trade-offs of stiffness, strength and energy
dissipation with various materials and reinforcement details. For instance, as the percentage of fine
aggregate in HPFRCC is increased, the stiffness will increase but the ductility will decrease, thus
reducing the ability of the HPFRCC-steel combination to dissipate significant hysteretic energy. The
finite element modeling will build upon recent research on modeling HPFRCC materials under cyclic
loading [40, 41, 44, 65, 66], including rate dependent tests on HPFRCC that are currently underway at
Stanford. Based on the finite element modeling, various combinations of reinforcement and HPFRCC
mix design will be investigated under quasi-static cyclic shear loading to verify strength, stiffness,
ductility and damage to the shear panels. The reduced-scale panels will be tested as shown in Fig. 12.
The experiments will also serve to validate again the robustness of the bolted connections. A sandwich
panel design using HPFRCC will also be investigated for potential advantages in reduced damage and
ease of replacement.
Task 4: Development and Large Scale Validation of Energy Dissipating Rocking Braced Frame
Components (MAST) -- A series of experiments will be conducted in the MAST Laboratory to
investigate the cyclic performance of the braced-frame rocking system and components. Figure 13 shows
a typical configuration of the test specimen for a multi-story, multi-bay braced frame system with
HPFRCC shear panels, low-yield steel shear panels, BRC energy dissipating fuses, and structural pivots
D-13
at the base of the system. The dimensions will reflect those of the braced bent in the lower stories of the
prototype structures studied in Task 1, modeled at approximately one-third to one-half scale. This setup
will permit testing of several configurations of HPFRCC shear panels, the low-yield steel shear panels,
the axial column fuses, the pivots at the base connections, and the connections of these components to the
braced frame. The crosshead will be attached to pinned loading attachment points for each individual
braced frame to permit more independent motion of each frame, as shown in the figure. Quasi-static
loading will be primary in-plane (including gravity loading) with modest out-of-plane (orbital) loading to
simulate the realistic loads and deformations that would be experienced in a real building.
The purpose of these tests is to document the progressive inelastic response and damage in the complete
rocking system, with a primary focus on assessing the detailed response and robustness of the fuses, the
pivot assembly of the braced frames, and the connections of the fuses (both the HPFRCC and low-yield
steel shear panel fuses and BRC axial column fuses) to the braced frames. Because the energy dissipating
fuses are replaceable, several tests will be conducted using the braced frame system. The shear panel
fuses will be tested without axial column fuses, as well as with pairs of column fuses as shown in Fig. 13,
or with four column fuses as shown in Fig. 1. The specimens will be heavily instrumented so as to
provide comprehensive information for Task 7 on performance-based design of this structural system.
The Krypton system will also be ideal for documenting both the rocking component of the motion and the
shearing response of the HPFRCC and/or low-yield steel panels.
Telepresence Plan at MAST: The MAST Laboratory provides premier capabilities for remote teleparticipation for the other project participants, including those in Japan. Teleobservation will be achieved
through a set of ten remotely-controllable digital video cameras with directional audio microphones and
eight remotely-controllable high-resolution digital still image cameras spaced around the perimeter of the
specimen, and through an array of sensors (e.g., strain gages, displacement sensors, and rotation sensors).
Each video and still image camera is mounted on a robotic arm that can be extended vertically to increase
the coverage of the camera. Integrated teleoperation is provided for all cameras and the robotic towers so
that project participants may interact directly with the viewing environment. It is envisioned that the
project participants will work as a team during the experiments to study the response and make decisions
about the appropriate loading protocols. This is critical for this project, as it permits the contributions of
each researcher to this project to be brought to bear on the execution of these pivotal tests. All sensor,
video, audio, and still image information is streamed out over Internet2 for both private clients (i.e.,
project participants and other interested researchers) and
public clients (see discussion in Section D.7 on education
and outreach). Interfaces have been developed and
integrated into NEESgrid for use of these MAST-specific
features, providing a content rich environment to facilitate
detailed scientific interactions during these experiments.
Task 5: Parametric Design and Performance Assessment of Energy Dissipating Rocking Braced Frame
System -- Performance evaluation of the complete
structural system is a key aspect of the proposed research.
The performance evaluation will be conducted using the
basic framework methodology, originally developed
within the PEER Center and now being translated into
design guidelines through the ATC 58 effort. The primary
engineering performance metrics will be those related to
reparability (as inferred from residual drifts and damage
accumulation in the fuses) and safety (as inferred through
the mean annual frequency of collapse). The engineering
demand parameters (EDPs) will be processed through
D-14
Figure 13. Schematic Test Specimen of Steel
Braced Frame with Replaceable Energy
Dissipating Devices for MAST Laboratory
fragility (loss) curves to determine generalized decision variables, such as annualized losses to structural
and nonstructural systems and building content. A matrix of performance criteria will be established,
which will serve as the basis for an objective evaluation of various design options, including conventional
braced frame and moment frame designs and appropriate energy dissipating rocking systems. The
performance will be evaluated using incremented nonlinear time history analyses using the OpenSees
platform, including statistical evaluation of response data at various levels of intensity.
The variables that will receive attention in this parametric design and performance evaluation include:
•
•
•
•
Building configuration variables, such as plan size and number of stories
Relative strength and stiffness of energy dissipating braced frame and elastic moment frame
Systems with alternative fuse types and configurations, including single versus multiple fuses
Ground motion variables (intensity, frequency content, near-fault effects, etc.)
Task 6: Large Scale Validation of Energy Dissipating Rocking Braced Frame System (E-Defense) -The large-scale frame tests planned for the E-Defense shake table in Japan will integrate the results from
Tasks 1 to 5 and serves as a focal point to facilitate international research collaboration. The shake table
simulations, representing salient features of the complete structural system, will provide unprecedented
understanding of the interactive effects of braced frame rocking, energy dissipative fuses, and the elastic
restoring frame system. Conducting the tests at full-scale (or near full-scale) is important to accurately
represent the interactive behavioral effects of components and systems in the structural frame, the fuses
and their connections to the frame, and the slab/concrete floor deck. Our schematic design for the fourstory test frame (see Fig. 14) is configured to provide a versatile test-bed that can be used to evaluate
multiple types of fuse dissipaters. Aside from its large size and capacity, the E-Defense facility is
developing an innovative inertial mass system, which will dramatically simplify and reduce the cost of the
shake table test. As one of the important outcomes of the large-scale test is validation of our
computational simulation models, detailed response prediction analyses will be conducted prior to testing
(using OpenSees) and we will
encourage outside researchers
to make blind predictions of
the response.
The E-Defense facility is
uniquely suited to perform this
ultimate validation test. It is
the only one available,
worldwide, that permits closeto-full-scale shake table testing of a comprehensive
assembly that replicates all important interactions taking
place between all the components of a complete structure.
Such a validation test cannot be accomplished elsewhere,
and it comes at a small cost because of the great interest and
extensive complementary efforts of the Japanese project
collaborators.
Task 7: Design Implications and Recommendations -The combined experimental and analytical studies of Tasks
1 to 7 will result in a wealth of data and quantitative
information that need to be synthesized to become of direct
use to the engineering professions in the US and Japan. The
targeted audiences for these design recommendations are
code committees, guideline writers, professional
organizations, and individual practicing engineers. We will
D-15
Figure 14. Schematic Steel Frame
Specimen for E-Defense Shake Table Test
present concepts for these design implications and recommendations at least once per year to our external
advisory board, which will include several leading structural and earthquake engineering practitioners. In
particular, working committees of ongoing guideline development efforts, such as ATC 58, BSSC, and
the SEAOC Seismology Committee will be consulted during the course of this research and invited to
teleparticipate in testing. The PI (Deierlein) is a member of the ATC 58 committee, co-PI’s Hajjar and
Billington are active in other organizations that create standards (ASCE, ACI, FEMA, etc.). Midorikawa,
our Japanese counterpart, is active in building code committees of the Architectural Institute of Japan.
D6.2 Project Implementation
Team Organization, Management Plan, and Schedule: The project leadership team is diverse; led by a
PI from a non-NEES equipment site, with co-PI’s from both NEES and non-NEES sites; faculty are at
different stages in their careers, of different genders, and with different specialties (structural materials,
computational simulation, and earthquake engineering); our external advisory board of practicing structural engineers will have strong input; and our Japanese collaborator is assembling a complementary
research team in Japan. The organizational chart for our project is shown in Fig. 15. The management is
divided between four major initiatives, three of which encompass the major research task, with the fourth
being education and outreach (described in Sec. D.7). All the investigators and students will work integrally on the project, with each of the co-PI’s having a lead responsibility in one of the major thrusts.
Within each initiative are specific sub-tasks, which are the primary responsibility of the individuals listed.
The project will support three
PhD students, each of whom
will have the lead role on one
component of the research
with supporting roles on other
tasks. A functional budget for
the overall project is provide in
Sec.
D6.5,
which
is
supplemented
by
further
details in the full budgets and
budget justifications presented
later. The schedule of the
proposed tasks (as described in
Figure 15 – Project Management Organization
the previous section) is
summarized in Table 3.
During the development of this proposal, the co-PI’s have solicited input from practicing engineers and
developed effective working relationships, which they look forward to continuing throughout the project.
Input from a group of practicing structural engineers and building constructors will be formalized through
the creation of an external advisory board to whom the co-PI’s will provide with periodic updates and
meet with annually. The co-PI’s are already making regular use of commercial teleconference and webmeeting facilities, and they look forward to utilizing the enhanced collaboration technologies offered
Table 3 - Timing and Scheduling of Research Tasks
Proposed Task
Task 1 – Schematic Designs
Task 2 – Comp. simulations
Task 3 – HPFRCC Panels
Task 4 – Braced Bent w/Fuses
Task 5 – Parametric Designs
Task 6 – Braced Frame w/Fuses
Task 7 – Design implications
Report and Paper Publication
10/05 –
3/06
******
***
******
4/06 –
9/06
**
******
******
***
***
D-16
10/06 –
3/07
**
******
******
******
******
**
4/07 –
9/07
Dates
10/07 –
3/08
**
******
******
******
***
**
******
******
******
******
**
**
4/08 –
9/08
10/08 –
3/09
**
**
******
**
**
******
******
**
******
******
**
4/09 –
9/09
*****
******
******
through the NEESgrid. Interaction between the co-PI’s and sites is expected to be an on-going activity,
with formally scheduled web-meetings occurring at least once per quarter over the course of the project,
with at least one in-person meeting each year.
Risk Mitigation: All of the co-PI’s and senior personnel have experience with large projects involving
multiple organizations, large-scale testing, and international collaboration. As such, they appreciate the
challenges and risks to successful completion of the project. Details of a formal risk management plan
will be established upon the project award. Briefly, our primary strategy for risk mitigation will be
through (a) careful planning of the research activities, (b) paying careful attention to activities that can be
impacted by external factors (e.g., lab delays) and are on the critical path, (c) continuous monitoring of
our own progress, and (d) effective communication with team members, equipment sites, NEESinc, contractors, and others whose work progress will affect the overall project schedule. Budgeting of large tests
is another concern. We have been in contact with the UMN-MAST and E-Defense facilities, and we
think we have an accurate assessment of the testing expenses built into our budget. In the event of unforeseen cost over-runs (e.g., larger than expected bids from contractors to build the specimens) we do
have contingency plans to reduce test specimen sizes and modify the testing scope if necessary.
Use of NEESGrid Resources: NEESgrid resources are integrated into this research and education plan in
four fundamental ways:
• Telepresence activities as discussed in Task 4 (with similar expectations for Task 6 at E-Defense)
• Data sharing and archiving plans as discussed in Section D.6.3
• Education and outreach plans, specifically through the establishment of a public telepresence website
as discussed in Section D.7
• Extensive utilization and model development for the OpenSees platform [Tasks 2, 5], which has been
adopted as part of NEESGrid.
D6.3 Data Sharing and Archiving Plan and Dissemination to Earthquake Engineering Community
The MAST Laboratory provides outstanding facilities related to archiving of all sensor data (including
resistance strain sensors, displacement and rotation sensors, and 3D deformation data measured by a
Krypton LED-based system), video and audio data, and still image data. This data is synchronized and
archived on site at the MAST Laboratory during the experiment. Subsequent to the test, curation of the
data to the NEES national data repository is enabled with assistance from the MAST Laboratory staff.
The investigators have been leaders in advising on the establishment of data models and policies for data
curation within NEES (Hajjar sits on both the NEES Information Technology Committee and the NEES
Data Sharing and Archiving Committee; Deierlein and Krawinkler are on the NEES Board of Directors,
which has reviewed and approved these policies). It is our intent that this project serve as a model for
data curation, data sharing, and documentation of the research. Prior to conducting any experiments or
substantial analyses as part of this project, we will work with our students and the staff at MAST, EDefense, and NEESit to (1) establish key elements of data and metadata for timely and comprehensive
data documentation and curation, and (2) develop algorithms for data analysis and processing, such that
processed test data can be viewed and compared to analytical simulations during the tests. These steps
will help ensure that the data and metadata is posted to the NEES national data repository, consistent with
the policies of the NEES Consortium, Inc. We are committed to the NEES policy of uploading and
releasing the processed data to the NEES national data as soon as practically possible, and certainly
within the maximum timeframe specified in the data policies set by the NEES Board. Staff and student
time at the equipment sites have been budgeted for this effort. A similar archiving of OpenSees data will
be executed for all significant structural analyses conducted in this research.
Significant findings will be promptly submitted for publication in journals, workshops, seminars and conferences, and comprehensive documentation will be published in report series (such as the proposed
NEES electronic journal). All investigators will utilize membership and/or committee services in
D-17
professional organizations, such as EERI, ASCE, SEAOC, AISC, ACI, BSSC, and SSRC to communicate
findings so as to bring research results to engineering practice in an effective and timely manner. Finally,
during the last year of the project, we will hold a small workshop with our advisory board and other
invited select experts from academia and practice, where we present our research findings to facilitate
technology transfer.
D6.4 Payload Projects
Payload projects provide excellent opportunities for leveraging the proposed work and for broadening
participation. We will actively encourage other researchers, particularly younger faculty and faculty from
underrepresented groups, to collaborate. Possible payload projects for this research include: (1) Investigating alternative fuse designs, by re-using the rocking braced frame specimens at the MAST or EDefense facilities; (2) Developing alternative column rocking base connections through additional testing
on the MAST specimen; (3) Exploring new technologies for recording and interpreting three-dimensional measurements (e.g., laser-based displacement measuring devices); and (4) detailed 3D continuum
modeling to complement testing and macro-analysis to be performed in this project.
D6.5 Functional Budget
The functional budget of Table 4 provides a breakdown of the allocation of resources between the various
categories of research, education/outreach, and data archiving/sharing. All of the figures include indirect
charges (i.e., gross charges) and reflect the personnel and other supporting costs associated with each
activity. So, for example, in addition to the direct costs of the frame test specimen, the funding allocation
to the E-Defense testing includes the portion of salary and travel costs associated with the co-PI and
graduate students for time spent planning and conducting the frame test at E-Defense.
Specimen Disposal: Budgets for testing include costs for specimen disposal at the MAST and E-Defense
facilities (see detailed budget justifications).
Table 4 - Functional Budget (Total $)
ITEM
Experimental Research
Stanford
NEES-MAST
E-Defense
Non-Experimental
Education and Outreach
Data Archiving/Sharing
TOTAL
Year 1
80,000
62,798
44,000
52,718
32,500
16,250
288,266
Year 2
57,000
194,618
166,140
69,734
33,800
33,800
555,092
Year 3
0
90,372
244,920
107,752
35,152
35,152
513,348
Year 4
0
14,976
100,088
55,114
36,558
36,558
243,293
Cumulative
137,000
362,764
555,148
285,318
138,010
121,760
1,600,000
D.7 Education, Outreach, and Training
As indicated in the management organization chart (Fig. 15), plans for education and outreach contribute
significantly to project plans. Four major education and outreach components are planned for the project:
(1) project website and public teleparticipation, (2) outreach to high-school students, (3) research
involvement for undergraduate students, and (4) research involvement for graduate students. Creating
opportunities for students from under-represented minority groups is emphasized throughout the plan by
leveraging associations with existing programs and initiatives at the participating universities, the
participating NEES site, and the Pacific Earthquake Engineering Research (PEER) Center - the latter
being facilitated by three of the co-PI’s (Deierlein, Krawinkler, and Billington) involvement in PEER’s
research and education programs (see http://peer.ucsd.edu/). All activities will be coordinated and linked
with the NEES Consortium education and outreach activities.
Website and Teleparticipation: A project website will be created to promote research collaboration
among the research team and outreach to other researchers, students, and the public. The site will provide
D-18
a schedule of testing, with links to teleparticipation resources at the MAST NEES and E-Defense sites to
permit observation of the test and test data as it is being generated through the public client
teleparticipation interface. This project-specific website for public telepresence will include content
about the research status (particularly ongoing experimental testing) targeted for four different age levels
(e.g., primary school, secondary school, the general population and the primary target audience of
undergraduates in all fields).
Outreach to High School Students: The UMN Civil Engineering Department has an ongoing relationship with four Minneapolis high schools, with large under-represented minority populations (50 to 85%),
which teach a nationally certified pre-engineering curriculum, Project Lead the Way (PLTW). The UMN
EERI Student Chapter (for which Hajjar serves as advisor) currently engages these schools as well as
elementary and middle schools with demonstrations on earthquake engineering, including use of a model
shake table. Co-PI Hajjar will invite PLTW high school teachers to the MAST Laboratory for a half-day
workshop to help shape an educational module on earthquake engineering research.
Involvement of Undergraduate Students: Undergraduate students at the University of Minnesota and
will be involved on an ongoing basis as laboratory assistants at the NEES site. Beyond this, the project
has targeted plans for participation of under-represented minority groups in an Earthquake Engineering
Scholars Course (hosted annually by the educational program of the PEER Center) and summer research
internships at one or more of the sites. Funding has been allocated to involve undergraduate summer
intern students during each year of the project. Addition funds to support one or two undergraduates from
Stanford are likely to be available through a program supported by the Stanford Vice Provost for Undergraduate Education. Student recruitment will be done through existing mechanisms of the Engineering
Diversity Program (http://emp.stanford.edu/EDP/) at Stanford University, the PEER Educational Affiliate
Program, recruiting visits by the co-PIs to selected schools with large under-represented minorities.
Involvement of Graduate Students: This project will provide research support for three PhD students.
Our goal is for at least one of these students to be from an under-represented minority group. The co-PI’s
are committed to actively recruiting diversity students, through the undergraduate programs described
above and through programs offered by the Stanford School of Engineering Diversity Programs
(http://soe.stanford.edu/edp/home/index.html), which has dedicated fellowship funding for graduate
students from under-represented minorities.
D.8. Intellectual Merit and Broader Impacts on Earthquake Engineering Research and Practice
Intellectual Merit: The proposed research will lead to seminal advances in concepts, techniques, and
models for the design of controlled rocking mechanisms for steel building systems using replaceable
energy dissipating fuses. The fuses utilize novel materials and components, including combinations of
high-performance fiber reinforced cementitious composites (HPFRCC) shear panels fuses, low-yield steel
shear panel fuses, and buckling-restrained axial column fuses. This combined computational and experimental research investigates both component and complete system response, synthesizing the results
through a methodology for performance-based design that directly assesses losses in structural and nonstructural components. The proposed concept emphasizes preventing damage to foundations and other
structural elements that are difficult to repair; localizing damage in elements that are easy to replace;
providing story drift control so that nonstructural damage is reduced; and providing sufficient safety
against collapse. The research includes an international NEES/E-Defense collaboration with Japan,
leveraging US and Japanese facilities and resources. Large-scale experiments will be carried out to
validate the systems, coupled with the development of new computational models on the NEESgrid for
the novel materials involved. The project team is committed to fully utilizing the simulation,
visualization, and collaboration tools of the NEESgrid to achieve a seminal increase in the rate of data
assimilation, comprehension and learning, within the context of a distributed international project.
Broader Impact: The proposed research is expected to have a major impact on engineering practice,
providing the opportunity to design and construct damage tolerant, easy-to-repair, and cost effective
D-19
structural systems. A detailed data sharing and archiving plan for these complex large-scale tests and
parametric simulations will advance the state-of-art in model-based simulation and data archiving. The
project leadership team is comprised of co-PI's who are diverse in gender, age, and specialty, and who are
geographically well distributed at two non-NEES equipment sites and a NEES equipment site. The
project has a natural engineering education component through the research participation of graduate and
undergraduate students, including three Ph.D. students, undergraduate assistants, and summer
undergraduate research scholars. Using mechanisms available both externally and within this project, the
co-PIs are committed to attract and involve under-represented minority graduate, undergraduate, and
high-school students in various phases of the research. Diversity initiatives for undergraduate and
graduate students will leverage associations with the Engineering Diversity Program at Stanford
University and the education program of the NSF-EERC PEER Center. Outreach to diversity students at
high schools will be facilitated by collaboration with Project Lead the Way at the UMN NEES site.
D.9 Results of Prior NSF Support
Deierlein, G.G., (CMS-9632502, CMS-9896368, 9/1/96-7/31/00, $240,000)
“Seismic Design and Behavior of Composite RCS Frames”
Part of the US-Japan Cooperative Research Program on Composite and Hybrid Structures, the outcome of this project were: 1) development of nonlinear analysis methods to evaluate the seismic performance of composite steelconcrete frames, 2) development of improved seismic design requirements for composite construction, and 3)
formulation of plans for a large-scale validation test. The project resulted in a methodology to assess the collapse
limit state of frame structures that incorporates a cumulative damage index for composite frame components to
account for uncertainties introduced by earthquake ground motions. This project culminated in a pseudo-dynamic
test of a full-scale three-story composite frame conducted through subsequent collaboration with researchers in
Taiwan. One masters student and two PhD students participated in this project, publications include [39, 68, 69].
Billington, S. (CAREER Award, CMS-9984127 and CMS-0342940: July 00-June 04, $276,000.)
“Innovative Materials for Civil Infrastructure Education and Research”
This project involved course development and research on high-performance fiber-reinforced cement-based
composites (HPFRCC) in precast, post-tensioned bridge piers for seismic regions. A course entitled, Structural
Materials Testing and Simulation, which combines physical experiments and computational simulation, has been
offered 3 times at the undergraduate and graduate levels. Small-scale precast bridge column tests and large-scale
column tests using HPFRCC were completed. Pilot creep and shrinkage tests on HPFRCC were performed. A
constitutive model for cyclic and seismic 2D nonlinear finite element analysis of HPFRCC was developed.
Research on assessing the impact of introducing new structural systems and materials to construction practice
through life-cycle cost modeling continues from this project. One Masters student, two PhD students and two Postdoctoral researchers have been supported. Publications include [40, 44, 65] along with twelve conference papers.
A. E. Schultz, J. F. Hajjar, and C. K. Shield (CMS-9632506, 9/15/96-8/31/00, $253,896).
“Seismic Behavior of Steel Moment-Resisting Frames with Composite RC Infill Walls.”
This project included an experimental and computational research program for the study of steel moment-resisting
frames with composite reinforced concrete infill walls subjected to seismic excitation. A one-third scale frame was
tested quasi-statically to determine the cyclic behavior of steel frame-RC infill composite wall systems. Twelve
full-scale cyclic shear specimens, comprised of steel wide-flange sections connected with shear studs to a concrete
panel, were tested to quantify the strength of stud connections under cyclic shear and axial tension. Data analysis
coupled with linear and nonlinear system analyses and prototype structure design served to establish preliminary
analysis and design recommendations. One Ph.D. student and one M.S. student, selected references [70-76].
H. Krawinkler (PEER/NSF Project 3382003, 10/1/2003–3/31/2005, $90,000)
“Criteria for Performance-Based Design”
In this project the main goal was to develop criteria and procedures for performance-based design (PBD) that permit
direct (rather than iterative) design of frame and wall structures for multiple performance objectives associated with
limit states of relevance for a subsequent rigorous performance assessment. This involved focusing on discrete
performance targets associated with discrete hazard levels and proportion structural systems for strength, stiffness
(drift limitations), and ductility based on expected losses and an acceptable probability of collapse. Two Ph.D.
students, selected references, [8, 77-84].
D-20
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3.
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4.
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5.
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E-1
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E-2
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Composite Reinforced Concrete and Steel Moment Frame Structures,” Journal of Structural
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70. Tong, X., Hajjar, J. F., Schultz, A. E., and Shield, C. K. (2005). “Cyclic Behavior of Composite Steel
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E-4
71. Saari, W., Hajjar, J. F., Schultz, A. E., and Shield, C. K. (2004). “Behavior of Shear Studs in Steel
Frames with Reinforced Concrete Infill Walls,” Journal of Constructional Steel Research, Vol. 60,
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Steel Frames with Composite Reinforced Concrete Infill Walls,” Composite Construction in Steel and
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Engineering Foundation, American Society of Civil Engineers, Reston, VA, 983-994.
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Interaction In Steel Frames with Composite RC Infill Walls,” Paper No. 2727, Proceedings of the
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77. Ibarra, L.F., Medina, R.A., and Krawinkler, H. (2005). “Hysteretic Models that Incorporate Strength
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of Moment-Resisting Frames", accepted for publication in Earthquake Spectra.
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Proceedings of the 13th World Conference on Earthquake Engineering, Paper #116, Vancouver,
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Response of Frame Structures,” Proceedings of the 13th World Conference on Earthquake
Engineering, Paper #239, Vancouver, Canada.
82. Adam, C., Ibarra, L.F., and Krawinkler, H. (2004). “Evaluation of P-Delta Effects in NonDeteriorating MDOF Structures from Equivalent SDOF Systems,” Proceedings of the 13th World
Conference on Earthquake Engineering, Paper #3407, Vancouver, Canada.
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3rd International Conference on Earthquake Engineering, Nanjing, China, Oct. 18-20, 2004, pp. 212218.
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Proceedings of the 2004 SEAOC Convention, Structural Engineers Association of California,
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E-5
PROPOSAL TO THE U.S. NATIONAL SCIENCE FOUNDATION
“NEESR-SG: Controlled Rocking of Steel-Framed Buildings with
Replaceable Energy Dissipating Fuses”
Submitted for review to:
NSF NEES-Research Program on March 11, 2005
REVISED JULY 18, 2005
Principal Investigator:
Gregory G. Deierlein, Stanford University (lead organization)
Co-Principal Investigators:
Sarah Billington, Stanford University
Jerome Hajjar, University of Illinois
Senior Research Personnel:
Helmut Krawinkler, Stanford University
Mitsumasa Midorikawa, Building Research Institute (Japan)
E-Defense Liaison:
Masayoshi Nakashima, E-Defense (Japan)
NOTE – This document includes excerpts of the proposal necessary for the NEES compliance
check. Since the time that the proposal was submitted, one of the co-PI’s (Hajjar) has moved
from the University of Minnesota to the University of Illinois. In conjunction with this move, we
are proposing to move some of the testing from the Minnesota-NEES (MAST) to Illinois-NEES.
We have modified the plan based on the new testing location; however, there may be some
remnant references to the MAST facility in this write-up. These references should be interpreted
as now pertaining to Illinois-NEES.
Additionally, to accommodate the reduced budget, the research plan will primarily focus on
inelastic fuses consisting of HPFRCC panels. Alternative fuses, such as the Buckling Restrained
Braces (BRB) which were envisioned in the original proposal will still be considered in the
analysis study. However, the extent to which these will be tested in the physical experiments
will depend on soliciting donations of pre-qualified BRB dissipation devices from industry
sources in the US and Japan.
CONFIDENTIAL – NOT FOR DISTRIBUTION
D-1
D. PROJECT DESCRIPTION
D.1 - Project Participants
Table 1. Project Participants
Name
and
Title
Gregory G.
Deierlein
Professor
Affiliation
Stanford
University
Principal
Investigator
Sarah
Billington
Assoc. Prof.
Stanford
University
Co-Principal
Investigator
Jerome F.
Hajjar,
Professor
University
of Illinois
Expertise
Role in Project
Research management,
performance-based earthquake
engineering, nonlinear analysis,
design of steel and composite
steel-concrete structures,
development of building code
provisions.
Design and behavior of
structural concrete and
HPFRCC materials and
systems, computational
modeling of cementitious
composites.
Large-scale structural testing ;
nonlinear structural analysis
and design; performance-based
earthquake engineering.
Co-Principal
Investigator
Helmut
Krawinkler
Professor
Stanford
University
Performance-based earthquake
engineering assessment and
design, experimental and
analytical simulations.
Building
Research
Institute
(Japan)
Seismic design and behavior of
steel structures, large-scale
testing and shake table
simulations, Japanese building
code standards
Other Senior
Personnel
Mitsumasa
Midorikawa
Research
Coordinator
of Building
Technology
Other Senior
Personnel
D-2
Project coordination (PI);
schematic design and planning of
building systems; planning and
design of shake table test at EDefense, coordination of
education and outreach activities.
Planning, design, modeling and
testing of HPFRCC shear
dissipation panels, collaboration
on system test at NEES Illinois
and E-Defense; summer REU
advising.
Planning, design and execution of
medium- and large-scale quasistatic system tests; data archiving
and curation to NEES repository;
project website; education and
outreach activities.
Design and seismic performance
assessment of rocking wall
systems, building system studies,
coordination of wall-frame system
test at E-Defense and large-scale
test at Illinois.
Project coordination of Japanese
collaborators, development of
braced-frame rocking systems
following Japanese construction
practice, planning and design of
shake table test at E-Defense.
Time
Commitment
(mos./year)
2-2-2-2
0.75-0.75-075
0.5-0.75-0.750.5
0.5-0.750.5
1-1-1-1
D.2 - Utilization of NEES Equipment Resources, E-Defense and Stanford Experimental Facilities
Major testing will be conducted at the University of llinois-NEES facility and the E-Defense shake table
in Japan. In addition, material and small component testing will be conducted in the structural
engineering laboratory at Stanford University. Table 2 shows the planned occupation at each site.
Table 2. Scheduling for NEES and Major Equipment Site Usage (* = 1 month)
Site
10/1/05 – 9/30/06
10/1/06 – 9/30/07
***
N-Illinois
***
***
***
***
***
***
10/1/08 – 9/30/09
***
***
E-Defense
Stanford
10/1/07 – 9/30/08
***
***
***
NEES Illinois Laboratory: The Illinois system will be used to conduct the large-scale quasi-static cyclic
tests of the controlled rocking structural systems investigated in this research. These tests will
characterize the progressive damage and inelastic response of the structure and will validate the qualities
of the system. The proposed testing entails the use of two multi-axial testing boxes mounted on the
strong wall, in addition to high-resolution data acquisition systems for measurement and archiving of
loads, displacements, strains, and video images.
E-Defense Shake Table: The large 15 x 20 m shake table at the E-Defense facility in Japan will be used
to conduct dynamic tests of a large (near full-scale) building system with a hybrid rocking bracedmoment frame system with structural fuses. The E-Defense shake table is required to accommodate the
large-scale testing which is critical to investigate the energy dissipating fuse mechanisms and the hybrid
braced-moment frame system at a realistic scale. The large scale is necessary to accurately simulate the
behavior, which is necessary both from a scientific point of view (accurate representation and
understanding of the behavior) and to demonstrate the validity of the new rocking fuse system to
engineers and other stakeholders. Apart from its large size, the E-Defense facility provides other benefits.
The lab is developing an inertial system to apply gravity loads and seismic mass in multi-story building
models. This inertial frame will simplify the shake table test setup and make the test more economical.
Another benefit is that this proposed project will leverage financial and intellectual resources of a
companion Japanese project that will be funded by the Japanese government (see supporting letter from
Dr. Nakashima, Director of E-Defense).
STANFORD Structural Engineering and Materials Lab: The Structural Engineering and Materials
Lab at Stanford University has a strong floor and several loading frames that can be used for
development testing of the shear panel fuses. The laboratory is equipped with loading actuators,
measurement transducers, and data acquisition systems. The lab also houses equipment for fabrication,
curing and testing of high performance fiber reinforced cementitious composite (HPFRCC) materials.
For materials testing there are two MTS testing machines; one is an 89 kN (tension/compression), fatigue
rated machine with hydraulic grips, the second is a 245 kN (tension/compression), fatigue rated machine
with a 1 x 2 meter loading table. This facility has access to the high-speed Internet-2 and can be used for
internet-based collaboration (e.g. telepresence) and NEES data archiving for this project.
D-3
EXCERPTS FROM PROPOSAL RELATED TO NEES-ILLINOIS TESTS
Proposed Braced-Frame Fuse System: As illustrated in Fig. 1, the proposed research focus is on the
development of a seismic force resisting system that combines desirable aspects of conventional steelbraced framing (or equally valid, of reinforced concrete walls) with two alternative and complementary
fuse concepts – shear panel fuses and axial column fuses. The framing configurations shown are two
examples of possible variants that can be envisioned with this system. The underlying concept of the
system utilizes controlled rocking (pivoting) and a capacity design approach to concentrate inelastic
deformations in the fuse components. The configuration of Fig. 1a demonstrates the application of a
shear panel fuse, where energy is dissipated through the large shear strains developed across the shear
panel between the braced frames. For a given story drift, the magnitude of shear strain energy dissipated
in the panel is proportional to the ratio of the dimensions of the braced panel to the shear panel, i.e., the
dimensions B/A shown in Fig. 1a. Thus, by altering the geometry, one can achieve large amplifications in
shear deformations, whereby large amounts of energy can be dissipated at low drifts. Ideally, the shear
panels should have a large elastic stiffness, a well defined yield point, and large energy dissipation
capacity. Two materials that will be
investigated for the shear panels are
high-performance
fiber
reinforced
cementitious composites (HPFRCC) and
low-yield steel plates. The panels are
connected to the frame with bolts (or
dowels) and are designed for easy
access and replacement. This is in
contrast to conventional systems, such
as eccentrically braced steel frames or
coupled shear walls, where the shear
links are integral with the structural
system and difficult to repair once they Figure 1 – Pivoting Braced Frame (a) single bent with shear
are damaged. Likewise, the inelastic dissipating panels, (b) dual bent with shear dissipating panels and
hinge regions of moment frames are axial dissipating strut
integral to the structural frame and
difficult to repair.
The configuration shown in Fig. 1b demonstrates the use of axial column fuses, which can either be
designed to work on their own or in combination with the shear dissipation panels. The axial deformations of a fuse are related to the bay width by the ratio of bracing panel width to story height (A/H). One
way to implement the axial column fuses is through the use of buckling-restrained columns (BRCs),
similar in concept to buckling-restrained braces (BRBs) that have been successfully introduced into
design practice over the past ten years [1]. Like their BRB counterparts, the BRCs would be designed to
dissipate energy through large inelastic deformations of a steel core, which is prevented from buckling by
some type of housing (often a steel tube filled with concrete). Another candidate for the axial column fuse
is a yielding base plate, such as Midorikawa et al. [2] have studied. The configuration of Fig. 1b
demonstrates where it may be advantageous to employ both axial column and shear panel fuses, so as to
improve response or redundancy of the systems.
D-4
For optimal building performance, the fused
bracing systems (Fig. 1) are intended for use with
a parallel system that provides an elastic restoring
force. As suggested by the framing plan in Fig. 2,
we envision that the parallel system to be a flexible moment resisting steel frame. The combination of the stiff fused braced frame and the flexible frame offers several advantages over
conventional systems or either system acting
alone. By balancing the strength, stiffness, and
inelastic deformation characteristics of the two
systems, the goal is for the moment frame to
remain essentially elastic under the design
earthquake, thereby providing a restoring force
that will reduce (or even eliminate) residual drifts.
This is in contrast to conventional dual systems,
where both systems are expected to deform
inelastically and their interaction is unknown.
After large earthquakes, when the fuses may be
damaged, the moment frame will stabilize the
system while the fuses are removed and replaced.
Figure 2 – Schematic framing plan for hybrid system:
energy dissipating braced frames with elastic moment
frames
NEES/E-Defense Collaboration: The proposed research will be an international collaboration between
US and Japanese participants and will utilize the NEES Illinois and the E-Defense facilities. With one of
the key objectives being to validate the proposed system for use in engineering practice, the E-Defense
facility provides the unique capabilities to perform dynamic shake table tests of a nearly full-scale
building prototype. The research topic is of mutual interest to the Japanese researchers and industry. A
team under the leadership of Dr. Midorikawa (Research Coordinator of Building Technology at the
Japanese Building Research Institute) has been identified; and, as indicated in the attached letter from Dr.
Nakashima (Director of E-Defense), funding for Japanese collaborators has been secured. The co-PI’s
have a long history of collaboration with Japanese researchers, and over the course of developing this
proposal we have corresponded extensively with Dr. Nakashima and Dr. Midorikawa. They both are
enthusiastic about collaborating with us on this project, and we have included Midorikawa as a co-leader
to direct the proposed collaborative testing at the E-Defense facility. Should this proposed be funded, we
also expect that the Japanese will become involved in the proposed testing at the NEES Illinois facility
and send visiting researchers to the U.S.
D.6 Strategic Research Plan
As illustrated in Fig. 11, the research plan is organized around a central spine of activities that integrate
the data and results of the experimental simulations into a coherent systems design approach, culminating
in the development of design implications and recommendations for the new structural framing systems.
The details associated with each task are described later in sub-sections of Section 7.1. Briefly, the main
features of the plan are the following:
Task 1 – Schematic Design of Prototype Systems: Much like in engineering design practice, the research
will begin with a detailed schematic design effort to articulate and quantify the important issues and
parameters for the subsequent experimental and analytical studies. Performance-based design thinking
will guide this effort with consideration given to life-cycle and post-earthquake repair costs.
D-5
Task 2- Computational Simulation: As
schematic designs are developed,
computational models will be created
and tested to simulate the nonlinear
seismic response of the structures.
Included will be development of models
to simulate unique features of the
rocking behavior and inelastic fuses,
utilizing existing data on low-yield and
BRB steels (from previous research) and
HPRFCC panels (obtained from Task
3).
Task 3 – Characterization and Design
of HPFRCC Panels: Guided by sizing
and performance parameters identified
through the schematic design effort of
Task 1, this task will focus on the development of HPRFCC panels. Data
from HPRFCC material and panel testFigure 11 – Strategic Research Plan
ing and computational modeling will
provide input to characterize the panels response in the macro-simulations (Task 2) and large-scale
validation tests at Illinois (Task 4). A complementary effort (upper right box of Fig. 11) will synthesize
data on BRBs and low-yield strength steel for energy dissipation.
Task 4 – Development and Large-Scale Validation of Energy Dissipating Rocking Frames (NEESIllinois): This task integrates data from the schematic designs, computational simulation results,
HPFRCC shear panel study (Tasks 1 to 3) and low-steel shear panel, to design and test the rocking braced
frame subassembly and fuses. Quasi-static tests will be conducted at large scale in the Illinois facility,
with the primary goals to (a) characterize the shear panel and axial column fuses, and (b) validate that the
system and components (e.g., the brace pivot) work as intended.
Task 5 – Parametric Design and Performance Evaluation of Building Systems: Building upon the schematic designs (of Task 1), the simulation models (Task 2), and the experimental simulation data (Tasks 3
and 4), the parametric design studies pull together the information to conceive and assess a number of
alternative designs. One outcome of this task will be data to plan and design the shake table specimens to
be evaluated at E-Defense (Task 6). The other outcome will be information feeding into the design
implications and recommendations of Task 7.
Task 6: Large-Scale Shake Table Simulation (E-Defense): Data, models and knowledge gained from
Tasks 1-6 will be synthesized and validated through the planning, design and simulation testing of a
large-scale frame on the E-Defense shake table. The frame will be designed as a test bed to permit
simulation of alternative fuse concepts and will be a focal point of US-Japan research collaboration.
Task 7 – Design Implications and Recommendations: The data and information collected and made
accessible through NEES-grid will provide a unique opportunity to accelerate research dissemination on
rocking braced systems with fuses into engineering practice. Design implications and recommendations
will be developed with the participation of professional engineering organizations.
D-6
D6.1 Detailed Project Tasks
TASK 3 – TESTING AT STANFORD UNIVERSITY
Task 3: Characterization and Design of HPFRCC Energy Dissipating Shear Panels -- To develop
the energy-dissipating shear panels for the large-scale rocking braced frame tests will require two main
research tasks: (1) Finite element (FE) modeling to identify optimal HPFRCC properties and their
combination with steel reinforcement, and (2) Reduced-scale panel testing to evaluate panel properties
and verify connection detail behavior. FE modeling will be used to identify the trade-offs of stiffness,
strength and energy dissipation with various materials and reinforcement details. For instance, as the percentage of fine aggregate in HPFRCC is increased,
A
the stiffness will increase but the ductility will decrease, thus reducing the ability of the HPFRCCsteel combination to dissipate significant hysteretic
energy. The finite element modeling will build
upon recent research on modeling HPFRCC
HPFRCC
Shear Panel
materials under cyclic loading [40, 41, 44, 65, 66],
including rate dependent tests on HPFRCC that are
currently underway at Stanford. Based on the finite
element modeling, various combinations of
reinforcement and HPFRCC mix design will be
A-A
A
investigated under quasi-static cyclic shear loading
Figure 12 Shear panel test set-up
to verify strength, stiffness, ductility and damage to
the shear panels. The reduced-scale panels will be tested as shown in Fig. 12. The experiments will also
serve to validate again the robustness of the bolted connections. A sandwich panel design using
HPFRCC will also be investigated for potential advantages in reduced damage and ease of replacement.
TASK 4 – TESTING AT ILLINOIS-NEES
Task 4: Development and Large Scale Validation of Energy Dissipating Rocking Braced Frame
Components (Illinois-NEES) -- A series of experiments will be conducted in the Illinois Laboratory to
investigate the cyclic performance of the braced-frame rocking system and components. Figure 13 shows
a typical configuration of the test specimen for a braced frame system with HPFRCC shear panels, lowyield steel shear panels, and structural pivots at the base of the system. The dimensions will reflect those
of the braced bent in the lower stories of the prototype structures studied in Task 1, modeled at
approximately one-third to one-half scale. This setup will permit testing of several configurations of
HPFRCC shear panels, the low-yield steel shear panels, the pivots at the base connections, and the
connections of these components to the braced frame. The top of the frame will be attached through
pinned fixtures to the NEES Loading and Boundary Condition Boxes for each individual braced frame to
permit more independent motion of each frame. Quasi-static loading will be primary in-plane (including
gravity loading) with modest out-of-plane (orbital) loading to simulate the realistic loads and
deformations that would be experienced in a real building.
D-7
The purpose of these tests is to document the
progressive inelastic response and damage in the
complete rocking system, with a primary focus on
assessing the detailed response and robustness of the
fuses, the pivot assembly of the braced frames, and the
connections of the fuses (both the HPFRCC and lowyield steel shear panel fuses) to the braced frames. To
the extent permitted by the budget or otherwise made
available through industry donations, vertical Buckling
Restraint Column (BRC) fuses will also be investigated.
Because the energy dissipating fuses are replaceable,
several tests will be conducted using the braced frame
system. The specimens will be heavily instrumented so
as to provide comprehensive information for Task 7 on
performance-based design of this structural system. We
would like to explore use of the Close-Range Digital
Photogrammetric System (or other optical methods) to
document both the rocking component of the motion
and the shearing response of the HPFRCC and/or lowyield steel panels.
Figure 13. Schematic Test Specimen of Steel
Braced Frame with Replaceable Energy
Dissipating Devices for Illinois Laboratory
Telepresence: The Illinois-NEES Laboratory provides premier capabilities for remote teleparticipation for
the other project participants, including those in Japan. Teleobservation will be achieved through a set of
remotely-controllable digital video and still image cameras spaced around the perimeter of the specimen,
and through an array of sensors (e.g., strain gages, displacement sensors, and rotation sensors). It is
envisioned that the project participants will work as a team during the experiments to study the response
and make decisions about the appropriate loading protocols. This is critical for this project, as it permits
the contributions of each researcher to this project to be brought to bear on the execution of these pivotal
tests. All sensor, video, audio, and still image information is streamed out over Internet2 for both private
clients (i.e., project participants and other interested researchers) and public clients.
Task 5: Parametric Design and Performance Assessment of Energy Dissipating Rocking Braced
Frame System -- Performance evaluation of the complete structural system is a key aspect of the
proposed research. The performance evaluation will be conducted using the basic framework
methodology, originally developed within the PEER Center and now being translated into design
guidelines through the ATC 58 effort. The primary engineering performance metrics will be those related
to reparability (as inferred from residual drifts and damage accumulation in the fuses) and safety (as
inferred through the mean annual frequency of collapse). The engineering demand parameters (EDPs)
will be processed through fragility (loss) curves to determine generalized decision variables, such as
annualized losses to structural and nonstructural systems and building content. A matrix of performance
criteria will be established, which will serve as the basis for an objective evaluation of various design
options, including conventional braced frame and moment frame designs and appropriate energy
dissipating rocking systems. The performance will be evaluated using incremented nonlinear time history
analyses using the OpenSees platform, including statistical evaluation of response data at various levels of
intensity.
The variables that will receive attention in this parametric design and performance evaluation include:
•
•
•
•
Building configuration variables, such as plan size and number of stories
Relative strength and stiffness of energy dissipating braced frame and elastic moment frame
Systems with alternative fuse types and configurations, including single versus multiple fuses
Ground motion variables (intensity, frequency content, near-fault effects, etc.)
D-8
Task 6: Large Scale Validation of Energy Dissipating Rocking Braced Frame System (E-Defense) -The large-scale frame tests planned for the E-Defense shake table in Japan will integrate the results from
Tasks 1 to 5 and serves as a focal point to facilitate international research collaboration. The shake table
simulations, representing salient features of the complete structural system, will provide unprecedented
understanding of the interactive effects of braced frame rocking, energy dissipative fuses, and the elastic
restoring frame system. Conducting the tests at full-scale (or near full-scale) is important to accurately
represent the interactive behavioral effects of components and systems in the structural frame, the fuses
and their connections to the frame, and the slab/concrete floor deck. Our schematic design for the fourstory test frame (see Fig. 14) is configured to provide a versatile test-bed that can be used to evaluate
multiple types of fuse dissipaters.
Aside from its large size and
capacity, the E-Defense facility is
developing an innovative inertial
mass
system,
which
will
dramatically simplify and reduce
the cost of the shake table test. As
one of the important outcomes of
the large-scale test is validation of
our computational simulation models, detailed response
prediction analyses will be conducted prior to testing
(using OpenSees) and we will encourage outside
researchers to make blind predictions of the response.
The E-Defense facility is uniquely suited to perform this
ultimate validation test. It is the only one available,
worldwide, that permits close-to-full-scale shake table
testing of a comprehensive assembly that replicates all
important interactions taking place between all the
components of a complete structure. Such a validation
test cannot be accomplished elsewhere, and it comes at a
small cost because of the great interest and extensive
complementary efforts of the Japanese project
collaborators.
Figure 14. Schematic Steel Frame
Specimen for E-Defense Shake Table Test
D6.2 Project Implementation
Team Organization, Management Plan, and Schedule: The project leadership team is diverse; led by a
PI from a non-NEES equipment site, with co-PI’s from both NEES and non-NEES sites; faculty are at
different stages in their careers, of different genders, and with different specialties (structural materials,
computational simulation, and earthquake engineering); our external advisory board of practicing structural engineers will have strong input; and our Japanese collaborator is assembling a complementary
research team in Japan. The organizational chart for our project is shown in Fig. 15. The management is
divided between four major initiatives, three of which encompass the major research task, with the fourth
being education and outreach (described in Sec. D.7). All the investigators and students will work integrally on the project, with each of the co-PI’s having a lead responsibility in one of the major thrusts.
Within each initiative are specific sub-tasks, which are the primary responsibility of the individuals listed.
The project will support three PhD students, each of whom will have the lead role on one component of
the research with supporting roles on other tasks. A functional budget for the overall project is provide
D-9
in Sec. D6.5, which is supplemented by further details in the full budgets and budget justifications
presented later. The schedule of the proposed tasks (as described in the previous section) is summarized
in Table 3.
During the development of this proposal, the co-PI’s have solicited input from practicing engineers and
developed effective working relationships, which they look forward to continuing throughout the project.
Input from a group of practicing structural engineers and building constructors will be formalized through
the creation of an external advisory board to whom the co-PI’s will provide with periodic updates and
meet with annually. The co-PI’s are already making regular use of commercial teleconference and webmeeting facilities, and they look forward to utilizing the enhanced collaboration technologies offered
through the NEESgrid. Interaction between the co-PI’s and sites is expected to be an on-going activity,
with formally scheduled web-meetings occurring at least once per quarter over the course of the project,
with at least one in-person meeting each year.
Risk Mitigation: All of the coPI’s and senior personnel have
experience with large projects
involving
multiple
organizations,
large-scale
testing,
and
international
collaboration. As such, they
appreciate the challenges and
risks to successful completion
of the project. Details of a
formal risk management plan
will be established upon the
project award.
Briefly, our
Figure 15 – Project Management Organization
primary strategy for risk
mitigation will be through (a) careful planning of the research activities, (b) paying careful attention to
activities that can be impacted by external factors (e.g., lab delays) and are on the critical path, (c)
continuous monitoring of our own progress, and (d) effective communication with team members,
equipment sites, NEESinc, contractors, and others whose work progress will affect the overall project
schedule. Budgeting of large tests is another concern. We have been in contact with the Illinois-NEES
and E-Defense facilities, and we think we have an accurate assessment of the testing expenses built into
our budget. In the event of unforeseen cost over-runs (e.g., larger than expected bids from contractors to
build the specimens) we do have contingency plans to reduce test specimen sizes and modify the testing
scope if necessary.
Use of NEESGrid Resources: NEESgrid resources are integrated into this research and education plan in
four fundamental ways:
• Telepresence activities as discussed in Task 4 (with similar expectations for Task 6 at E-Defense)
Table 3 - Timing and Scheduling of Research Tasks
Proposed Task
Task 1 – Schematic Designs
Task 2 – Comp. simulations
Task 3 – HPFRCC Panels
Task 4 – Braced Bent w/Fuses
Task 5 – Parametric Designs
Task 6 – Braced Frame w/Fuses
Task 7 – Design implications
Report and Paper Publication
10/05 –
3/06
******
***
******
4/06 –
9/06
**
******
******
***
***
D-10
10/06 –
3/07
**
******
******
******
******
**
4/07 –
9/07
Dates
10/07 –
3/08
**
******
******
******
***
**
******
******
******
******
**
**
4/08 –
9/08
10/08 –
3/09
**
**
******
**
**
******
******
**
******
******
**
4/09 –
9/09
*****
******
******
•
•
•
Data sharing and archiving plans as discussed in Section D.6.3
Education and outreach plans, specifically through the establishment of a public telepresence website
as discussed in Section D.7
Extensive utilization and model development for the OpenSees platform [Tasks 2, 5], which has been
adopted as part of NEESGrid.
D6.3 Data Sharing and Archiving Plan and Dissemination to Earthquake Engineering Community
The NEES-Illinois Laboratory provides outstanding facilities related to archiving of all sensor data
(including resistance strain sensors, displacement and rotation sensors, and optical deformation data,
video and audio data, and still image data. This data is synchronized and archived on site at the NEES
Laboratory during the experiment. Subsequent to the test, curation of the data to the NEES national data
repository is enabled with assistance from the NEES Laboratory staff.
The investigators have been leaders in advising on the establishment of data models and policies for data
curation within NEES (Hajjar sits on both the NEES Information Technology Committee and the NEES
Data Sharing and Archiving Committee; Deierlein and Krawinkler are on the NEES Board of Directors,
which has reviewed and approved these policies). It is our intent that this project serve as a model for
data curation, data sharing, and documentation of the research. Prior to conducting any experiments or
substantial analyses as part of this project, we will work with our students and the staff at NEES-Illinois,
E-Defense, and NEESit to (1) establish key elements of data and metadata for timely and comprehensive
data documentation and curation, and (2) develop algorithms for data analysis and processing, such that
processed test data can be viewed and compared to analytical simulations during the tests. These steps
will help ensure that the data and metadata is posted to the NEES national data repository, consistent with
the policies of the NEES Consortium, Inc. We are committed to the NEES policy of uploading and
releasing the processed data to the NEES national data as soon as practically possible, and certainly
within the maximum timeframe specified in the data policies set by the NEES Board. Staff and student
time at the equipment sites have been budgeted for this effort. A similar archiving of OpenSees data will
be executed for all significant structural analyses conducted in this research.
D6.4 Payload Projects
Payload projects provide excellent opportunities for leveraging the proposed work and for broadening
participation. We will actively encourage other researchers, particularly younger faculty and faculty from
underrepresented groups, to collaborate. Possible payload projects for this research include: (1) Investigating alternative fuse designs, by re-using the rocking braced frame specimens at the Illinois or EDefense facilities; (2) Developing alternative column rocking base connections through additional testing
on the Illinois specimen; (3) Exploring new technologies for recording and interpreting three-dimensional measurements (e.g., laser-based displacement measuring devices); and (4) detailed 3D continuum
modeling to complement testing and macro-analysis to be performed in this project.
D6.5 Functional Budget
The functional budget of Table 4 provides a breakdown of the allocation of resources between the various
categories of research, education/outreach, and data archiving/sharing. All of the figures include indirect
charges (i.e., gross charges) and reflect the personnel and other supporting costs associated with each
activity. So, for example, in addition to the direct costs of the frame test specimen, the funding allocation
to the E-Defense testing includes the portion of salary and travel costs associated with the co-PI and
graduate students for time spent planning and conducting the frame test at E-Defense.
Specimen Disposal: Budgets for testing include costs for specimen disposal at the Illinois and E-Defense
facilities (see detailed budget justifications).
D-11
Table 4 - Functional Budget (Total $)
ITEM
Experimental Research
Stanford
NEES-Illinois
E-Defense
Non-Experimental
Education and Outreach
Data Archiving/Sharing
TOTAL
Year 1
Year 2
Year 3
Year 4
62,000
49,000
34,000
41,000
25,000
12,000
223,000
44,000
151,000
129,000
54,000
26,000
26,000
430,000
0
70,000
190,000
84,000
27,000
27,000
398,000
0
12,000
78,000
43,000
28,000
28,000
189,000
Cumulative
106,000
282,000
431,000
222,000
106,000
93,000
124,0000
D.7 Education, Outreach, and Training
As indicated in the management organization chart (Fig. 15), plans for education and outreach contribute
significantly to project plans. Three major education and outreach components are planned for the
project: (1) project website and public teleparticipation, (2) research involvement for undergraduate
students, and (3) research involvement for graduate students. Creating opportunities for students from
under-represented minority groups is emphasized throughout the plan by leveraging associations with
existing programs and initiatives at the participating universities, the participating NEES site, and the
Pacific Earthquake Engineering Research (PEER) Center - the latter being facilitated by three of the coPI’s (Deierlein, Krawinkler, and Billington) involvement in PEER’s research and education programs (see
http://peer.ucsd.edu/). All activities will be coordinated and linked with the NEES Consortium education
and outreach activities.
Website and Teleparticipation: A project website will be created to promote research collaboration
among the research team and outreach to other researchers, students, and the public. The site will provide
a schedule of testing, with links to teleparticipation resources at the Illinois NEES and E-Defense sites to
permit observation of the test and test data as it is being generated through the public client
teleparticipation interface. This project-specific website for public telepresence will include content
about the research status (particularly ongoing experimental testing) targeted for four different age levels
(e.g., primary school, secondary school, the general population and the primary target audience of
undergraduates in all fields).
Involvement of Undergraduate Students: Undergraduate students at the University of Illinois will be
involved on an ongoing basis as laboratory assistants at the NEES site. Beyond this, the project has
targeted plans for participation of under-represented minority groups in an Earthquake Engineering
Scholars Course (hosted annually by the educational program of the PEER Center) and summer research
internships at one or more of the sites. Funding has been allocated to involve undergraduate summer
intern students during each year of the project. Addition funds to support one or two undergraduates from
Stanford are likely to be available through a program supported by the Stanford Vice Provost for Undergraduate Education. Student recruitment will be done through existing mechanisms of the Engineering
Diversity Program (http://emp.stanford.edu/EDP/) at Stanford University, the PEER Educational Affiliate
Program, recruiting visits by the co-PIs to selected schools with large under-represented minorities.
Involvement of Graduate Students: This project will provide research support for three PhD students.
Our goal is for at least one of these students to be from an under-represented minority group. The co-PI’s
are committed to actively recruiting diversity students, through the undergraduate programs described
above and through programs offered by the Stanford School of Engineering Diversity Programs
(http://soe.stanford.edu/edp/home/index.html), which has dedicated fellowship funding for graduate
students from under-represented minorities.
D-12