2018 NACE Conference Wisconsin Dells, WI. Joseph Cheung P.E. FHWA Office of Safety

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1 2018 NACE Conference Wisconsin Dells, WI Joseph Cheung P.E. FHWA Office of Safety

2 Skid related crashes are determined by many factors: Tire issues Weather Conditions Friction Demand Road Geometry Vehicle Speeds Driver Actions Vehicle Characteristics

3 Forces Acting on a Vehicle R N F c W N = centrifugal force = weight = normal force f = side friction V = vehicle speed e = superelevation R = curve radius f W f F c e Arizona ITE/IMSA Spring Conference March 2 nd, 2017

4 What is a High Friction Surface Treatment? High Friction Surface Treatments (HFST) are pavement surfacing overlay systems with: - exceptional skid-resistant properties that are not typically acquired by conventional materials - and retains the higher friction property for a much longer time. Commercially available resin-based products and processes Generally applied in short sections to improve spot locations where friction demand is critical.

5 Why High Friction Surface Treatment? HFST is effective in reducing crashes: Horizontal Curves and Ramps Intersections or braking conditions Grades Combination of all of the above Picture Courtesy Illinois DOT

6 Texas Curve Margin of Safety Margin of Safety = Friction Supply Friction Demand Recommended Distance Upstream of the PC to Begin HFST Application Curve Locations: Point of Curvature (PC) Middle of Curve (MC) Point of Tangency (PT)

Epoxy-Resin 3-4 hours 70+ F Rosin-Ester As soon as it reaches ambient

7 Bonding Agents Binder Quickest Curing Time* Curing Temperature Binder Curing Time Curing Temp. Epoxy-Resin 3-4 hours 70+ F Rosin-Ester As soon as it reaches ambient temperature ambient temp. Polyurethane-Resin 2.5 hours Methyl Methacrylate 1.5 hours <20F to 100+F Polyester-Resin 2 hours <40F to 100+F

8 HFST Aggregates Recommended aggregate is calcined bauxite which provides the highest resistance to polishing. Typically referred to as a 3 mm aggregate Calcined Bauxite

9 Typical Macrotexture Depths & Friction Factors Textures that affects friction Microtexture W ave e gth 0.5 mm Amplitude mm Macrotexture Macrotexture Wavelength mm Amplitude mm Microtexture

10 Commonly used Aggregate for HFST consideration Aggregates Calcined Bauxite Taconite Basalt Emery Flint Granite Silica Steel Slag

11 NCAT Aggregate Durability Study Phase I Laboratory Samples

12 Manual Installation Manual mixing of epoxy material Manual application of epoxy with squeegee Hand broadcast and distribution of aggregate Production rates: SY/hr.

13 Manual Installation Video

14 Mechanically Assisted Installation Machine mixing of binder Machine assistance in getting aggregate close to final position Binder distribution often by pump but total reliance on squeegees to attain binder thickness Production Rates: 1800 S.Y./hr.

Mechanically Assisted Installation May or may not include machine mixing of binder Binder distribution may include a pump but total reliance on squeegees to

15 Mechanically Assisted Installation May or may not include machine mixing of binder Binder distribution may include a pump but total reliance on squeegees to attain binder distribution and thickness Aggregate is sprayed to final position Production Rates: 1800 S.Y./hr. This category also includes the aggregate sprayed on

16 Automated Installation Machine mixes binder Machine places binder at final location Binder depth monitored constantly by machine Aggregate is placed by machine at final location within seconds of binder Handwork is limited to irregular areas Production Rates: 2800 SY/hr.

17 Sprayed Aggregate Mechanically Assisted Installation Video

18 AUTOMATED APPLICATION

19 Manual vs. Fully-Automated Comparison A manual application of HFST was compared with a fully automated application. The fully-automated HFST process installed 350 sq. yd. of full lane width in approx. 8 minutes, while the manual application installed 100 SY in 15 minutes (6 times faster). Benefits of using the fully-automated processes include: Improved speed and quality result in reduced installation time; Consistent proven specification; Full lane width 12 continuous operation in one pass; No material component waste; Reduced exposure of workers to live traffic; and Even application of binder and aggregate.

20 The Marquette Interchange Milwaukee, WI Systems interchange Junction of I-94, I-43, & I-794 Reconstruction completed in August 2008

21 Marquette Interchange

22 TOTALS Before HFST (11/08 8/11) 2 years, 10 months 219 crashes HFST Applied 9/21/2011 After HFST (10/11 8/14) 2 years, 11 months 9 crashes

25 Install HFST Summer of 2012

27 How Long Does HFST Last? The most significant issue is existing pavement condition We are expecting 10+ years based on accelerated test track results and current project experience But it depends on having a good specification and a good installation

28 Pavement Distresses Rutting Block Cracking Severe Fatigue Cracking Transverse Cracking 28

29 HFST Safety Effectiveness Study Total Crashes Ramps CMF = 0.48 Curves CMF = 0.63 Wet Road Crashes Ramps CMF = 0.21 Curves CMF = 0.37 Details: 8 State Naïve Study (includes a 25% penalty per HSM)

30 HFST Safety Effectiveness Study Total Crashes Ramps CMF = 0.65 Curves CMF = 0.76 Wet Road Crashes Ramps CMF = 0.14 Curves CMF = 0.48 Details: Study with comparison sites (includes a 25% penalty per HSM)

PA DOT Implementation of HFST RwD Safety Implementation Plan - 2012 PA DOT utilized the curve sections identified in the plan to install HFST to reduce RwD crashes and wet crashes using HSIP

31 PA DOT Implementation of HFST RwD Safety Implementation Plan PA DOT utilized the curve sections identified in the plan to install HFST to reduce RwD crashes and wet crashes using HSIP funding Using Bauxite and an epoxy binder for HFST Conduct Benefit/Cost Analysis Collect crash data for 15 locations in 2 counties approx miles of roadway HFST installations of three years or longer

Average Cost Benefit Table (15 locations) All 15 locations Annual Reduction Annual Reduction per locations Crashes Fatalities Major/moderate/ minor injuries PDO Unknown Severity

32 Average Cost Benefit Table (15 locations) All 15 locations Annual Reduction Annual Reduction per locations Crashes Fatalities Major/moderate/ minor injuries PDO Unknown Severity Economic Savings Due to Reduction in Fatality/Injury $5,361, $357, Benefit/Cost ratio :1 Averaged.04 lives saved per location

33 State DOT HFST Status Active implementation as of 12/1/2017 MA MD NJ, DE, No curves One curve 2 10 curves curves curves Over 100 curves Over 2 million S.Y.

34 HFST A Game Changer Something so simple could be this effective at stopping Run-Off the Road Crashes Keep Vehicles on the road - Eliminate the needs to replace roadside hardware Compensate for distracted drivers and driving too fast for the conditions the only safety countermeasure that require minimal human interaction. Reduced both wet and dry crashes. Dramatic crash reductions Marquette Interchange from 219 crashes (2 year, 10 months) to 9 crashes (2 year, 11 months) Cost effectiveness CA DN-199, $14,000,000+ for curve realignment to approx. $250,000 for HFST. Realignment takes 2 to 5 years to 4 to 6 months for HFST. Negligible environmental impact no additional impervious area created Minimize traffic delay - maintain 1 lane of traffic and eliminate the need for detour and reduce secondary crashes- reopen to traffic the same day

Questions and Discussion Joseph.cheung@dot.

35 Questions and Discussion

High Friction Surfaces In Missouri

High Friction Surfaces In Missouri Next Exit Nicole Hood, P.E. Assistant State Design Engineer Before High Friction Surface Treatment The Marquette Interchange After High Friction Surface Treatment The