7. High-Friction-Surface-Treatments.pptx (Read-Only)

2/9/15 I. What is High Friction Surface Treatment (HFST)?
II. Friction Number vs. Skid Number vs. Coefficient of Friction
III. Why friction matters?
IV. NCAT aggregate durability testing phase I
Jesse De Los Santos & Bruce Barrett
January 20, 2015
V. Aggregate cost comparison
VI. Methods of application
VII. Reusing aggregate
VIII. Causes of aggregate loss and delamination
High Friction Surface Treatment consists of:
1.  Calcined Bauxite, the wearing surface aggregate
• produced by heating at temperatures of 1650 to1700ºC.
• Imported from China and Guyana.
Source: Mike Moravec: Senior Highway Engineer Federal Highway Administration
2015 Nebraska Concrete Paving Associa9on Workshop 1 2/9/15 Resin + Hardener
Heat
2. Polymeric Binder Resin (proprietary mixtures)
• Epoxy-resin
• Polyester-resin
• Polyurethane-resin
• Acrylic-resin
• Methyl Methacrylate
→
Final Hardened Product
Source: “Quest for Calcined Bauxite”, Alison Tran,
www.ogneupor-spb.ru/besplatno/2.pdf
Table 1. Physical Requirements of the Polymer Binder Resin System
Property Viscosity Test Method ASTM D 2556 Polymer Binder Resin 7-30 poises Gel Time AASHTO M 235 10 minutes min. C o m p r e s s i v e ASTM C 579 1000 psi min. Strength*, 3 hr. C o m p r e s s i v e ASTM C 579 5000 psi min. Strength*, 7 days Ultimate Tensile
AASHTO M 235 @ 73
2500 psi min. deg. F Strength E l o n g a t i o n , a t AASHTO M 235 30-70% break point D u r o m e t e r ASTM D 2240 60-80 Hardness (shore D) Adhesive Strength
ASTM D 4541 250 psi min. or 100%
@ 24 hr substrate failure Cure Time, ”Dry
ASTM D 1640
3 hrs. max Through
Time” (prior to
traffic) LA Abrasion Test, Maximum Water Absorption AASHTO M 235 1% max *Mixed with aggregate.
Aggregate Gradation NDOR
HFST REQUIREMENTS
Rotation Direction of motion Friction Force, F µ=
Table 2: Bauxite Aggregate Requirements
20.0 100% Min. Passing No. 4
95.0 – 100% Passing No. 6
0.0– 5.0% Passing No. 16
0.0 – 1.0% Passing No. 30 AASHTO T96 0.20% AASHTO T255 Sodium Sulfate Soundness,
Maximum Loss 12% AASHTO T104 Aluminum Oxide Content,
Minimum 87% NDR C25 Moisture Content, Maximum 2015 Nebraska Concrete Paving Associa9on Workshop AASHTO T27 F
Fw
Eq. 1
The results of the locked-wheel test are reported as a friction
number (FN, or skid number [SN]), which is computed using
the following equation:
FN(V) = 100µ = 100*(F/W)
Source: 2009 NCHRP: Guide for Pavement Friction
2 2/9/15 Why Friction Matters
Double the Skid
Resistance & Halve
the Crashes
Friction Numbers Decrease with Age and Traffic Use
Source: 2009 NCHRP: Guide for Pavement Friction
Source: Investigation of Hot Mix Asphalt Surfaced Pavements Skid Resistance in Maryland State Highway Network
System, TRB 2006 Annual Meeting, Wenbing Song, et. al.
Ramps
Bridges
Curves
Stops
Friction Numbers for Portland Concrete using inverted Astro Turf
Source: MnRoad, April 2011, Tim Nelson, MnDOT
Skid Numbers for Nebraska’s Newly
Constructed Tined PCC are typically 54.
Skid Numbers for Nebraska’s Diamond Grinding
and Texturing Concrete Pavement are typically 46.
2015 Nebraska Concrete Paving Associa9on Workshop •Demand for friction increases when a driving
maneuver changes a vehicle’s speed or direction.
•When the demand for friction is greater than the frictional
force provided by the pavement, the potential for a crash
increases.
3 2/9/15 Crashes at Horizontal Curves
• Roughly 28% of all fatal crashes occurred at horizontal curves.
s
ay
ew
Bik
source: 2007 National Highway Traffic Safety Administration/Fatality Analysis Reporting System
• The average crash rate for horizontal curves it approximately three
times the crash rate of tangent sections.
EDC- Accelerating Innovation Technologies Deployment
and Shortening Project Delivery
• Roadway departure crashes that result from crossing the centerline or
leaving the traveled way make up 52% of non-intersection fatal crashes.
Sidewalks
Morganza Spillway Bridge
78,000 gallons of binder resin
3.5 miles long
2.5 Million pounds of HFST aggregate
Joseph.Cheung@dot.gov
Source: John LeFante Interstate Road Management
Comparison of Surface Treatments
Chip Seals
Immediately after Application
at 12 Months
Failure segments at 12 months
Microsurfacing
Immediately after Application
SN of 28 to 57
Increased at 12 Months
SN of 40 to 60
Continuous decline after 12 Months
WHAT SKID NUMBERS OR FRICTION NUMBERS CAN WE
EXPECT FROM HFST?
NDORs specification states, “The minimum acceptable
friction number (FN40R) is 65.” Our test procedure is
based on ASTM E274.
NDOR skid tests with a locked wheel testing trailer.
SN 50-70
SN 44-52
SN 20-30
Ultra Thin Bonded Wearing (UTBW) course, initial
at 33 Months
SN 48 to 59
SN 32 to 39
Dense graded HMA overlays, initial
at 12 Months
SN 35 to 52
SN 30 to 40
Fog Seals reduce friction by 20 to 33% until they return to the original
SN after about 12 months.
Source: Shuo Li, Indiana Department of Transportation, Evaluation of Pavement Surface Friction Treatments.
Publication FHWA/IN/JTRP-2012/04. Joint Transportation Research Program.
2015 Nebraska Concrete Paving Associa9on Workshop 4 2/9/15 NCAT Aggregate Durability Study Phase I
Source: David Merritt (Transtec Group), Mike Moravec(FHWA), Mike Heitzman(NCAT), High Friction
Surface Treatment Aggregate Durability Study, 9/16/14.
Costs:
High Friction Surface Treatment
Bridge
1 layer $25/SY
2 layer $47/SY
Epoxy Polymer Overlay (Flint)
2 layer $43/SY
Calcined Bauxite, $725/Ton
Flint, $200/Ton
1 layer $5.43/SY
1 layer $1.50/SY
NCAT Aggregate Durability Study Phase I – Test Track
Sections
Additionally the cost of perpetuating HFST every 8 years
needs to be taken into consideration.
Flint
Bauxite
Source: David Merritt (Transtec Group), Mike Moravec(FHWA),
Mike Heitzman(NCAT), High Friction Surface Treatment Aggregate
Durability Study, 9/16/14.
2015 Nebraska Concrete Paving Associa9on Workshop 5 2/9/15 NCAT Aggregate Durability Study Phase I
– Test Track Sections
Source: David Merritt (Transtec Group), Mike Moravec(FHWA), Mike Heitzman(NCAT), High Friction
Surface Treatment Aggregate Durability Study, 9/16/14.
Vacuum and Sweep to Remove Loose Aggregate
Causes of Aggregate Loss
• Inadequate depth of resin applied
• Inadequate mixing of the binder components
• Use of damp aggregate
• Foot or vehicular traffic after gelling but prior to curing
Causes of Delamination
• Surface moisture too high
• Improper surface preparation
Recovered Calcined Bauxite can be
reused if:
• Free of debris
• Meets gradation & moisture
requirements
2015 Nebraska Concrete Paving Associa9on Workshop 6 2/9/15 Weather Limitations:
Pavement temperatures must be between 60º F and 100º F
PROJECTS
2014
77-2(161), BNSF/Middle Creek, CN 13089
10,462 SY
1 layer $25/SY
17779 SY
2 layers $47/SY
275-7(193), Waterloo South, CN 22463
By Change Order
3332 SY
2 Layers, $65/SY
2015
275-7(1044), Waterloo Viaduct Friction Course, CN 22613
47031 SY $17.25/SY 1 layer
680-9(34), SB I680 to EB I80 Ramp, Omaha, CN 22596
10444 SY $20.50/SY 1 layer
Jesse De Los Santos & Bruce Barrett
January 20, 2015
2015 Nebraska Concrete Paving Associa9on Workshop 7 2/9/15 ž  Cramer
ž  Project
& Associates – Prime
Includes HFST Installation
•  McGill Restoration (Omaha, NE) – Sub-Contractor
ž  Bridge
Rail Sealing
ž  Expansion Joint Repair
•  Work Performed in 2015
ž  Grade
Beam Installation (North End)
•  Work Performed in 2015
ž  New
Approaches (North End)
•  Work Performed in 2015
ž HFST
installed on Four Structures
•  BNSF Viaduct – 2 Structures
–  Lengths were approx. 1760’ to 1770’
•  Middle Creek – 2 Structures
–  Lengths were approx. 350’
ž Concrete
Pavement
ž Asphaltic Pavement
2015 Nebraska Concrete Paving Associa9on Workshop ž Overall
Lengths on 4-Lane HWY 77
Including Shoulders
•  SB Approx. 2900’ x 2 Lane
•  NB Approx. 3100’ X 2 Lane
ž Ramps
In Addition to Mainline
•  SB HWY 77 Off Ramp to Rosa Parks Way – 430’
•  NB HWY 77 On Ramp from Rosa Parks Way – 615’
8 2/9/15 ž  Husker
Football
•  4 Home Games In One
Month
•  Off Road 3:00 pm Friday
Prior to Home Games
•  Allowed back on Road
9:00 am following
Sunday
ž  Labor
Day
•  Off Road by 3:00 pm
Friday Before
•  Back on Road Tuesday
following holiday
ž SB Inside Lane
•  Began Surface Prep on 8/24
•  Test Strip Installed 8/25
•  Work Called off for week due to rain
•  Labor Day Weekend
•  Unable to Begin work until Tuesday 9/2
–  Surface prep during day, HFST overnight
–  High Surface Temps
•  Off Road on 9/5
–  Home Football Game
•  Finished ¾ length of SB Inside Lane
2015 Nebraska Concrete Paving Associa9on Workshop ž Summer Heat/Direct Sun Exposure
•  Causes Surface Temp to raise above Spec.
–  Maximum Surface temp of 100˚F
•  Night Work
ž Cooler Weather
•  Temp Can’t drop below 55˚F within 8 hrs. of
placement.
ž Rain/Moisture
•  Any moisture penetrating surface negates
moisture test, and another will be performed
ž  SB
Outside Lane and NB Inside Lane
•  Began Preparing Surface Sunday 9/7
–  Surface prep during day, HFST installed day and night
–  Cooler Temps
•  Able to work from 9/7 to 9/19
–  No Home Football Game
•  Finished remainder of first lane and two additional lanes
ž  NB
Outside Lane
•  Began Surface Prep on 9/21
–  Surface prep during day, HFST installed day and night
–  Cooler Temps
•  Off Road on 9/26
•  Finished One Lane
9 2/9/15 ž Completed
Installation of Approximately
28,500 SY of HFST WITHIN 34 DAYS!
•  Also completed all cleaning and sealing of the
rails
ž Minor
repairs to HFST were taken care of
in one day
2 LAYER
1 LAYER
ž 
Concrete Pavement
ž 
•  BNSF Viaducts
•  Short stretches between
BNSF Viaduct and Middle
Creek Bridges
ž 
Asphaltic Pavement
Bridge Decks
•  Middle Creek Bridges
ž 
ž 
SAFETY of HFST
Seal/Preserve Deck
•  South of Middle Creek
Bridges
ž 
Main purpose of HFST is to
enhance SAFETY
2015 Nebraska Concrete Paving Associa9on Workshop 10 2/9/15 ž  Aggregate
•  60 LB sample taken to Central Lab
•  Tested for
–  Gradation
–  Sodium Sulfate Soundness
–  Aluminum Oxide Content
–  Difficulty meeting Specification
–  Signed Certificate of Analysis from Supplier
ž  Epoxy
•  16 oz. sample of each component to Central Lab
•  Tested for
–  Viscosity, Gel Time, Compressive and Tensile Strength,
Elongation, others…
ž Grinding
ž Shot Blasting
•  Slow Process
•  Up to three machines
operating at a time
–  20” Blast Pattern
–  Multiple Passes
•  Removes majority of
contaminants
•  Difficulty Removing
Piant
–  Several Passes
ž Pre
•  Isolated locations
•  Pavement Control
Filling Any Significant Damage
•  Slurry of Epoxy and Aggregate
•  Limit Slurry to Maximum of 3 Inch Depth
Joints
ž Pre
•  Labor Intensive
ž Sand
Blasting
•  Mainly used for rail
•  Spot locations on
Fill Joints
•  Help Prevent “Heave” In Material
–  Epoxy Fills Void Entirely
–  Aggregate Settles and Displaces
–  Leaves High Spots
deck and pavement
2015 Nebraska Concrete Paving Associa9on Workshop 11 2/9/15 ž Preparations
Complete…Almost Ready
For Installation
ž  18”x18” Plastic
ž  2
Hour Minimum
ž  Visible
Moisture, Test
Fails
ž  Up to Four 330 Gallon Totes At One Time
ž  Pump and Mixer
•  Accurately Pumps 1:1 Ratio of Parts A and B
•  Mixed and Applied at up to 4 Gallons per Minute
–  Total of Approximately 18,000 Gallons Applied
2015 Nebraska Concrete Paving Associa9on Workshop ž Dump
Truck
•  Store Aggregate
ž Venturi
Driven Eductor Systems
•  Aggregate Movement
ž Epoxy
Storage
ž Epoxy Mixer/Pump
•  Epoxy Movement
ž Applied
to the Surface Through Hose and
Wand from Pump
•  Spread Evenly on Surface Using a Notched
Squeegee
12 2/9/15 ž Application
on Pump
Rate Monitored with Gauge
ž Known Width of Application
•  Able to Mark Rail at Known Lengths
–  Known # of Gallons per X Feet
–  Additional Monitoring of Application Rate
ž  Spilling
Surface
of Epoxy On To
•  Any Epoxy Not Mixed
Thoroughly
–  Isolate Location
–  Re Prepare
–  Do Not Attempt to Mix by
Hand
ž  Re-Filling of Totes
•  Attempted in Effort to Save
Time
•  Single Part Spilled On
Deck
ž  Spread Evenly on Surface Using a Notched Squeegee
•  25-32 SF/Gal (1/16”) Minimum Coverage for One Layer
•  12-16 SF/Gal Minimum Coverage Per Layer for Two Layer
•  Worn easily, keep eye on notch depth
ž  Venturi
Driven
Eductor System
•  Air Moves Aggregate
• 
• 
• 
• 
2015 Nebraska Concrete Paving Associa9on Workshop from Bed of Dump
Truck
Agg. Blown Through
4” Hoses
Hand Applied on
Visible “Shiners”
Limit Foot Traffic
Once Agg is down.
Prohibit Traffic
Before Epoxy Begins
to Gel
13 2/9/15 ž Night Work
•  Some Existing
ž Entire Surface Is Swept
•  All Excess Aggregate is Picked Up and Salvaged
–  Granted No Contaminants
•  Second Layer Installed Immediately After
Lighting
–  Not enough to
perform work
Sweeping
•  Sweeping Not Allowed Until Epoxy is Fully
ž  Additional
Lighting
Was Needed
•  Globe on Tail End of
Trailer
•  Enhanced Visibility
Greatly
ž  Pull
Off Test
•  3/Lot
•  Lot = 1000 Lane Feet
•  Total of 12 Pull Off
Tests
•  24Hrs After
Installation
•  250 PSI Minimum
Cured
ž Calcined
Bauxite Runs Approx. $1250/
SuperSack (2 Ton)
•  Before Shipping Cost
•  Every Effort Mad to Salvage Material
ž Cramer
And Associates (Prime)
•  McGill Restoration (HFST Contractor)
ž 28,500
SY Of HFST
•  Over 13,000 Lane Feet
ž 4 Weeks
•  Day And Night
ž Total
Bid of $2.5 Million
•  $1.1 Million For HFST
Video Provided by McGill Restoration
2015 Nebraska Concrete Paving Associa9on Workshop 14