Pavement Preservation Journal - Fall 2011 - (Page 8)

Preservation Treatments Are Environmentally Sustainable By Jim Chehovits, P.E. and Larry Galehouse, P.E. oday’s pavement preservation treatments are environmentally sustainable strategies for road maintenance and life extension. Recent analyses of energy inputs and emissions outputs of pavement preservation treatments—compared T Table 1: Total Energy Use for Pavement Construction Materials (Chappat and Bilal, 2003) 8 to conventional rehabilitation and reconstruction practice— show that these treatments have significantly lower energy usage and greenhouse gas emissions than conventional rehab and reconstruction. In the analysis, the basics of energy use (inputs) and greenhouse gas (GHG) emissions for various pavement materials, construction processes, and pavement preservation techniques were considered. We also compared energy use and GHG emissions on an annualized life-extension basis. Any way it is looked at, pavement preservation techniques offer reduced energy inputs and lower GHG emissions compared to classic hotmix asphalt, and even warm-mix asphalt reconstruction techniques. Any pavement strategy will require a series of procedures that use energy and emit greenhouse gases. Pavement rehabilitation and reconstruction require large amounts of energy to obtain and process raw materials, transport, mix and apply the fi nal product, while pavement preservation processes require much less energy to apply the final product to the road surface. The big benefit is during the technique’s service life. We present data on energy usage per unit area of pavement life extensions via pavement preservation treatments and compare it to typical design lives of reconstruction and rehabilitation techniques. Pavement preservation treatments typically include spray-applied surface seals, thin overlays, crack treatments, chip seals, slurry seal/micro surfacing, surface recycling, and others. Each preservation treatment reduces damaging effects of aging and deterioration of the pavement surface layer and helps protect the integrity of the underlying pavement structure. If proactive preservation treatments are not used, pavements will deteriorate more rapidly, and will require major rehabilitation with structural overlays or reconstruction much earlier. Alternatively, conventional construction, rehabilitation and maintenance of pavements require obtaining, processing, transporting, manufacturing and placement of large amounts of construction materials, including base materials, aggregates, and asphalt cement or Portland cement binder. These conventional processes View past issues of the Pavement Preservation Journal online at

Table of Contents for the Digital Edition of Pavement Preservation Journal - Fall 2011

President’s Message
Preservation Treatments Are Environmentally Sustainable
Elevation, Deicer Impacts Crack Sealant Performance
In-Place Recycling Saves Energy, Cuts Emissions
Micro Surfacing Solves Hurricane-Induced Rutting
New ‘Roadmap’ to Guide Pavement Management Progress in United States
Congressman Visit to Repaver Plant Yields Big Dividends
Make Plans for ‘Music City’, 2012 Preservation Conference
Ninth Transportation Asset Management Conference Planned for San Diego
New Guidance for Preservation of High-Volume Pavements
News Briefs
Ontario’s Preservation Strategy is Environmentally Sustainable
Engineering Characteristics of Prime Coats on Granular Base
Calendar of Events
Index to Advertisers

Pavement Preservation Journal - Fall 2011