Road Rehabilitation Using Foamed Asphalt

During the Arab Oil Embargo of 1973, the price of crude oil quadrupled to $12 per barrel. Subsequently the price of asphalt, the bottom of the crude oil barrel, also increased significantly during this time and the cost of highway construction and rehabilitation rose dramatically. Contractors and equipment manufacturers quickly recognized that recycling reclaimed asphalt pavement (RAP) could provide many benefits and opportunities. Milling machines were developed, hot mix asphalt plants were modified to allow the addition of RAP to mixes, and soil stabilization equipment was redesigned to reclaim existing pavements in-place.