The 7 Annual Wooden Bridge Competition

The 7th Annual Wooden
Bridge Competition
RULES & GUIDELINES
Organizer
AUD – ASCE Student Chapter
Competition Date
Saturday, March 21st, 2015
9:00 am to 5:00 pm
Location
The American University in Dubai
E-Building Lawn (Open Area Behind E-Building)
WINNERS OF THE 6TH ANNUAL WOODEN
BRIDGE COMPETITION – 2014
FIRST PLACE WINNERS – ABU DHABI UNIVERSITY
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SECOND PLACE WINNERS – AMERICAN UNIVERSITY IN DUBAI
THIRD PLACE WINNERS – AMERICAN UNIVERSITY IN DUBAI
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OVERVIEW
The Annual Wooden Bridge Competition provides an opportunity for engineering students
to shine outside the confines of classrooms. The event brings together a wide variety of
students from engineering schools for friendly competitions centered around wooden
bridge testing. The competition, initiated and first held in 2008, has involved numerous
entries from Universities across the Emirates including the following:
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American University of Sharjah (AUS),
University of Sharjah (UOS),
Abu Dhabi University (ADU),
United Arab Emirates University in Al Ain (UAEU),
Herriot Watt University (HWU),
Dubai Men’s College (DMC),
Manipal University (MU),and
American University in Dubai (AUD).
This seventh annual competition promises to attract continued and expanded
participation from civil engineering programs throughout the UAE and GCC. Much
appreciation and gratitude to the Society of Engineers - UAE for their continuous support
and commitment in making the wooden bridge competition a success.
OBJECTIVES
Design and construction of model bridges enables students to explore concepts learned
in the classroom in a fun, friendly, inter-collegial environment. Student teams are required
to design and construct the most efficient bridge subject to the constraints specified
herein. It is expected that the competition will:
1. Provide students with a valuable learning experience which will serve as a means
of translating theoretical knowledge into practical knowledge.
2. Encourage a sense of teamwork among the students and foster the development
of the academic community.
3. Enable students to develop a sense of economy when consuming materials and
an understanding of non-technical constraints on design and construction.
4. Provide an amusing and informal yet technical event to encourage interaction
between GCC students and professors.
Prizes are provided to the bridge with the highest result of the following formula:
Formula = Strength Ratio + Points for Prediction
Strength Ratio =
Load
Weight1.5
, where load and weight are measured in kg.
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Points for Prediction are given based on the ratio
Ratio Value
0.90–1.10
0.8–0.89 & 1.11–1.20
0.7–0.79 & 1.21–1.30
Outside of these ranges
Actual Load
Predicted Load
Points given
5
3
1
0
Note that Points for Prediction are based on the most accurate estimation of applied load
under the condition of providing calculations that support the predicted load.
Compressive and tensile strength of wood and shear strength of glue will be provided.
On-site competitions will also be held to enrich the event.
COMPETITION RULES AND INSTRUCTIONS
Description:
The competition will consist of the design, construction and load-testing of a model
wooden bridge by student teams. Each team will be provided with all materials necessary
to construct the bridge.
Eligibility:
The competition is open to all engineering schools in the GCC. Up to three entries may
be submitted from each school. Every entry must be designed and assembled by a
team of students without any external professional assistance.
Team Compositions:
Student teams must consist of at least two students and at most five students. Every team
member must be a currently registered undergraduate student at their represented
University. Both full and part time students are eligible to participate on the student teams;
however, each student may only participate on one team (i.e. a student may not be part
of two or more different teams and may not contribute to two or more submissions). Each
team must further have a minimum of one full-time student currently enrolled in an
undergraduate civil or architectural engineering program. As this is an undergraduate
competition, graduate students may not participate within the teams. During the load
testing competition, each team must designate one individual as the team spokesman
and representative and two other members responsible for placing the bridge on the
supports. Any objections or questions not administered by the team representative
will result in IMMEDIATE DISQUALIFICATION of the submitting team.
Bridge Constraints:
The constraints of the competition are modified from year to year to give student teams
different challenges. In this year’s competition, the materials for the bridge comprise of
wood, glue, and plywood for gusset plates. Bridges must also conform to all geometric
requirements. There is only one restriction on the design types utilized; the bridge
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has to be made of at least two bays. Bridges will be tested using single point loading
at the mid-span apex and teams must accommodate the loading conditions in their
design. Any design may be employed as long as it is in conformance with the geometric
requirements, accommodates mid-point loading at an apex joint (see attached figure) and
utilizes only the materials provided.
Bridge Construction:
Each team will be required to design and build a bridge constructed from wooden
members and glue that will be distributed to each team entering the competition. It is not
necessary to use all types of materials distributed. No additional materials beyond
those distributed may be added. Materials will be weighed before distribution and the
bridge will be weighed before testing and the bridge will be inspected by the judges to
ensure that the bridge is in conformance with the material specification. The use of any
materials other than those provided will result in IMMEDIATE DISQUALIFICATION
of the submitting team.
Painting and Coatings
The bridge must be constructed using only the materials provided. No paint, stain or any
other coating or foreign substance is permitted on the bridge is allowed, of any sort.
GEOMETRIC CONSIDERATIONS
Design Span:
The clear design span is 2.0 meters (considered to be face of abutment to face of
abutment). The bridge should consist of a minimum of two bays. The bridge must be built
to accommodate additional seat lengths.
Bridge Seat Lengths:
Bridge seats, on each side of the bridge, cannot be longer than 25 centimeters. The total
length of the bridge is restricted to a maximum of 2.5 meters. Bridges more than 2.5
meters or less than 2 meters in total length will be disqualified.
Bridge Width (Out-to-Out):
Bridges must be between 400 and 500 mm wide measured (out-to-out dimensions as
measured from the outside left of the bridge to the outside right of the bridge perpendicular
to the bridge deck).
Height of Structure:
Each bridge must be between 300 and 500 mm high from the support level (overhead
clearance) and may have no more than 200 mm of underclearance (as measured from
the support level). The overall height of the bridge, as measured from the top chord
vertically to the bottom chord, may not exceed 700 mm total at any point.
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TESTING AND EVALUATION
Evaluation Criteria:
Bridges will be evaluated based on their load efficiency and load prediction accuracy. The
awards will be given to the highest values resulting from the formula.
Formula = Strength Ratio + Points for Prediction
Strength Ratio =
Load
Weight1.5
, where load and weight are measured in kg.
Points for Prediction are given based on the ratio
Actual Load
Predicted Load
to the teams that provide
calculations prior to testing the bridge.
Ratio Value
0.90–1.10
0.8–0.89 & 1.11–1.20
0.7–0.79 & 1.21–1.30
Outside of these ranges
Points given
5
3
1
0
For example, a bridge that carried 1050 N, weighing at 5 kg, and a predicted load of 1000
N will have a formula value of:
Formula =
1050N / 9.81m/
(5kg)
1.5
+ 5* = 14.57
*With a ratio of 1.05 in the range of 0.90–1.10, the bridge is awarded 5 points
For calculations, compressive and tensile strength of wood and shear strength of
glue will be provided.
Bridge Weight:
All materials will be weighed before distribution and each bridge will be weighed and
compared to the distributed material weight prior to testing. Again, any bridge which
weighs more than the material received will be immediately disqualified.
Testing Order:
Teams will be chosen for testing in random order. The order will be determined prior to
testing.
Judging Panel:
A judging panel, consisting of faculty members from participating universities (one faculty
per university), will validate whether the entry bridges have satisfied the competitions
requirement prior to testing. Disqualification will occur when and where the requirements
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have been violated. Faculty judges will further oversee the load testing of the structures.
The judges will only be available for validation of bridges from 9:30 am to 10:30 am.
Teams failing to show up within the allocated timing will be disallowed participation
in the bridge competition.
Test Load:
Load testing will be performed gradually with a steadily applied load by means of a frame
loading system (see attached picture). The load will be applied at mid-point loading at an
apex joint (see attached figure). Loading will be performed until failure. Failure occurs
when either members or joints rupture or buckle thereby prohibiting the structure from
carrying additional load or when the structure exceeds the maximum deflection of 5 cm
as recorded at mid-span.
Maximum Vertical Bridge Deflection:
The maximum allowable bridge deflection is 5.0 cm. This will be measured and recorded
at the mid-span of the bridge at support level.
Minimum Load:
The minimum allowable load to qualify for awards is 900 N (91.7 kg). This will be
measured as the load is applied at the apex of the bridge.
ON-SITE COMPETITIONS
Fun events will be held throughout the day to permit schools to compete in events
complementary to the bridge load testing. The following events are expected:
- Tug-o-War
- Apple-in-a-Bowl
- Three-legged Race
- CE Jeopardy
Additional fun events are being planned to enhance the on-site fun. The rules and
constraints will be distributed on-site and all participating schools will have the opportunity
to form teams for each competition.
AWARDS
There will be two categories of awards:
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Bridge Load Efficiency and Prediction Awards: The Society of Engineers - UAE
has generously supported and sponsored this event and allocated the following
awards for the first three winners:
- First Place: AED 5,000
- Second Place: AED 3,000
- Third Place: AED 2,000
On-Site Events Awards: Awards will also be given to the teams who win the onsite events held throughout the day.
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We look forward to hosting our largest and best competition yet
See you on March 21st
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