High Friction Surfacing
High Friction Surfacing has a long history of proven use in saving lives by imparting the highest level of skid resistance onto a road surface. High Friction Surfacing is available as hot or cold applied systems. The cold applied technique involves the even application of a tough polymeric liquid binder onto the road surface followed by the application of calcined bauxite aggregate. The hot applied systems involve the application of a hot pre-mixed material consisting of binder and calcined bauxite.
The concept was first investigated in the USA during the 1950's using epoxy resin binders and was first known as “Anti-skid Surfacing”. In the UK, the first evaluation trials were conducted in 1967 for the Greater London Council. The study over a period of 12 months demonstrated a 50% reduction in accidents and casualties on roads treated with High Friction Surfacing.
The use of High Friction Surfacing was fairly limited in the 1970's due to its relative high cost and limited highway budgets. Applications grew steadily in the 1980's when Highway Engineers could balance the cost of High Friction Surfacing against a broader savings strategy. Effectively, budgets were allocated for Accident Investigation and Prevention, demonstrating returns on the investment in High Friction Surfacing at Accident Black Spots compared with the savings in casualty reduction.
The growth of High Friction Surfacing accelerated in the late 1980's and early 1990's, largely in parallel with the Traffic Calming Act and the development of alternative resin processes to the original epoxy resin systems.
When to Use High Friction Surfacing
- On sites where there is high risk of accidents resulting from collisions between vehicles or between vehicles and pedestrians e.g. on approaches to pelican crossings, roundabouts, junctions and crossings.
Cost effectiveness
- Tragic loss of life or serious injury has an immeasurable cost to the accident victims, their families and friends.
- Financially, there are major cost consequences for emergency services, local and national governments. It is estimated that one fatality on a non-motorway road costs £1.4M and on a motorway £1.7M.
Which roads can be treated with High Friction Surfacing?
- All classes of road, from single track, unclassified roads to high speed urban routes, trunk roads and motorways can and have been successfully treated.
- High Friction Surfacings can be specified in accordance with The Specification for Highway Works Clause 924.
Some important benefits and features
- Designed to enhance the skid resistance of trafficked surfaces
- A high strength veneer surfacing, typically 3-5mm thick
- Durable able to withstand high braking and shearing forces
- Should only be applied onto sound substrates that have been well prepared and are in fair to good condition
- Accredited for substrates with a texture depth up to 2mm
- Can be specified by referring to The Specification for Highway Works Clause 924 (PDF)
- Regulated in the UK under the Highways Agency BBA HAPAS scheme
- Accredited by the British Board of Agrément (BBA) certification scheme covering products and approved installers
- BBA "Type 1" High Friction Surfacing is the highest classification attained
("Type 3" lowest classification) - Design Manual for Roads and Bridges deals with the design standards for Highways. The relevant standards for High Friction Surfacing in these documents are: -
Environmental considerations
- Accident levels will be reduced by imparting the highest attainable skid resistance
- The rapid speed of the process means that disruption to road uses, local businesses and emergency services is minimised.
Life expectancy
- Careful attention to material selection and installation has provided service lifetimes of typically 5 - 10 years.
Summary
- High Friction Surfacing is an established, proven process for saving lives by imparting the highest level of skid resistance onto any road surfacing.
- It is an extremely cost effective solution when compared to the value prevention by avoiding collision related fatalities.
- Installed by specialist companies and organisations.
- Requires well trained operatives and specialist plant.
- Suitable for all vehicular traffic.
- Adaptable to cycleways or pedestrian surfaces.
- Commonly referred to as "Anti-skid" Surfacing.