A pilot study is conducted to investigate the techno-economic feasibility of application of crumb rubber modified bitumen (CRMB) as stress alleviating membrane (SAM) and substitute to thin hot mix overlay. This study aims at optimization of blend of bitumen and crumb rubber (CR), design of blending system for preparation of blend at site, optimization of quantity of blend to be used with respect to severity of cracks and distress. Findings of the study reveal that 10 per cent CR powder by weight of binder, having 0.15-0.60 millimetre (mm) size, is an optimum blend. The periodic performance study of test sections indicate that performance of single coat SAM is comparable to 25 mm thick hot mix overlay and may last for about 3-4 years on a busy National Highway. Also, it uses 66 per cent less bitumen and saves 58 per cent of the cost of maintenance. The details are discussed in the paper. (a) For the covering entry of this conference, please see ITRD abstract no. E217099.
Samenvatting