Pavement Types
Open Graded Friction Course PDF Print E-mail
Written by Carl Thodesen   
Open graded friction courses (OGFC) are typically characterized by an HMA mixture with a high void content, created by using a greater amount of coarse aggregate. Benefits commonly associated with this type of pavement include the rapid removal of water from the roadway surface, improved overall skid resistance, and reduced noise emissions.

Another aspect of OGFC pavements which requires attention is the selection of an appropriate binder for the mix. OGFC mixes generally require greater film thicknesses than dense graded mixes. For this reason, it is very common to use modified asphalts, as these tend to exhibit the necessary film thicknesses for OGFC applications. Asphalt rubber in particular has been used very often in open graded mixes and has been shown to maintain the "open" structure of the pavement even in extreme weather conditions. 
Last Updated ( Tuesday, 30 June 2009 22:35 )
Read more...
 
Stone Mastic Asphalt PDF Print E-mail
Written by Carl Thodesen   
Stone Mastic Asphalt (SMA) was initially developed in Europe to minimize the effects of studded tires on pavements. Since its introduction to the USA, it has primarily been used for its resistance to permanent deformation, noise reduction, and for its increased durability. 

SMA is composed of crushed coarse aggregate, crushed fine aggregate, mineral filler, asphalt cement, and a stabilizing agent. One of the main design requirements for an SMA mix design is the resistance to draindown of the binder. Research confirms that draindown can be prevented through the use of fibers and/or polymers. Studies have shown that asphalt rubber can be used without additional fibers to achieve the draindown requirements of SMA pavements. Additionally, the increased elasticity of asphalt rubber also prevents the formation of thermal cracking in SMA pavements.
Last Updated ( Tuesday, 30 June 2009 22:36 )
Read more...
 
Chip Seal PDF Print E-mail
Written by Carl Thodesen   
Monday, 08 December 2008 20:18
Chip sealing involves spraying an asphaltic material followed by the distribution of a thin layer of aggregate cover. Properly designed chip seals are economical, easy to place, and reasonably durable. They provide a water proff cover for the existing pavement surface and also resist surface abrasion by traffic. Additional performance benefits have been seen when chip sealing is done using rubberized asphalt binder. Due to the decreased temperature susceptibilityt of rubberized binders, rubberized chip seals typically demonstrate longer lives and provide smoother rides.










ECOPATH has extensive experience in suggesting the right pavement types to certain climatic zones/countries, moreover ECOPATH is dedicated to developing solutions with economic efficiency as a priority. Please contact us for further information on mix and binder design services. 
Last Updated ( Tuesday, 30 June 2009 22:36 )