ABSTRACT
Chip seals are one of the most effective surface treatments for preserving the existing pavements. However, there is no unified design method of such treatments in the United States. The existing design procedures adopted by road agencies are based on many assumptions relating to the asphalt-aggregate interaction and alignment. Hence, there is a need to develop design procedure for chip seal pavements addressing the primary distresses (aggregate loss & bleeding) as well as the assumptions with respect to aggregate orientation. The objective of this study was to develop a performance based design procedure for design of chip seal treatments. The experimental program involved preparation of chip seal samples and performing image analysis (aggregate orientation), sweep test (aggregate loss) and wheel tracking test (bleeding). The methodology developed in this study is based on the aggregate loss, bleeding as well as aggregate orientation to consider effect of the traffic on the re-alignment of the aggregates with time. Comparative analysis with respect to the existing methodologies also been presented to evaluate the rationality of the new methodology.
