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 Marquette Interchange Friction Surface Treatment
What is a High Friction Surface Treatment (HFST)? Pavement surfacing overlay system with: Exceptional skid-resistant properties that are not typically acquired by conventional materials. And retains the higher friction property for a much longer time. Generally applied in short sections to improve spot locations where friction demand is critical. Estimated cost is around $22 per sqyd.
What is a High Friction Surface Treatment (HFST)? Materials Aggregate- Generally calcined bauxite or slags with high resistance to polishing, but flint, granite and other materials have also been used. Resin Binder System- Generally Epoxy or Methyl Methacrylate Resins used.
Aggregate Durability Study Taconite Emery 15 Steel Slag Silica Basalt Flint 100 Bauxite Granite
Why High Friction Surface Treatments? Maintaining pavement friction is critical for safe driving HFST significantly increases surface friction for automobiles Safety treatment Speed countermeasure
A Safety Design Alternative Works well for reducing stopping distance and loss of control at Sites with high occurrences of skid related crashes, such as Sharp horizontal curves Intersection approaches Loop ramps At 60 MPH on wet or dry pavement, HFST can reduce stopping distances up to 40%.
Other Locations where HFST has been Used Nationwide Kentucky In 2010, Kentucky applied HFST at 75 locations. Went from 483 crashes in previous 3 years to 61 in the 3 years since the HFST application. South Carolina Between Oct 2008 and Nov 2010, South Carolina installed HFST at 6 locations. Overall crash reduction of 70% at those locations.
So What about Missouri?
High Friction Surfaces in Missouri
High Friction Surfaces in Missouri
High Friction Surfaces in Missouri
High Friction Surfaces in Missouri
Tuesday, November 27, 2007 U.S. Route 54 at Jefferson Street Fiery tanker crash and explosion near bridge Route 54 and Jefferson Street closed during incident and traffic detoured
High Friction Surfaces in Missouri 50 40 30 20 10 0 2000 2005 2010 2013 U.S. 54 Curve Crash History
High Friction Surfaces in Missouri
High Friction Surface Treatment
Surface Preparation? Job spec? Aggregates and binders? How to Have Successful Project Application Method? Weather Limitations?
High Friction Surfaces in Missouri Materials Aggregate Calcined Bauxite was required, which has shown the highest resistance to polishing Resin Binder System Epoxy or Methyl Methacrylate Resins allowed Weather Limitations Dry surface with Air and Pavement temperatures above manufacturer s recommendation Surface Preparations Thoroughly cleaned, joints/cracks > ¼ inch filled HFST not placed over markings or rumble strips
High Friction Surfaces in Missouri Job Specifications Used language from Caltrans and AASHTO As well as some of our own to develop the best fit for MoDOT Application Methods Applied by either mechanical or manual techniques Work Zone Traffic Management Plan One month to complete 14 days of work Night work Traffic Control by MoDOT forces Project Awarded for around $84,000
High Friction Surfaces in Missouri
High Friction Surfaces in Missouri
How is the HFST Working? Friction did improve: HFST section friction value - 85 Adjacent pavement around 40 Crashes have reduced: Comparison of crash data in both EB and WB directions for same 2 month period from 2011 to 2013 (Nov.1 Mar.1) 20 15 17 10 13 5 0 3 2011 2012 2013
High Friction Surface Treatment
HFST in Missouri What s NEXT?
HFST in Missouri What s NEXT? Aggregate might be others that work Received funding for peer exchange in KY Applying for AID to get $1M (accelerated implementation and deployment) Every Day Counts Exchange in June
Questions? More Information?