ABSTRACT
Abstract Asphalt overlay is often one of the effective measures of improving the performance of the existing concrete pavements, but a problem commonly encountered with this measure is the "reflective cracking” in the asphalt overlays. In China several measures, such as SAMI, geotextile etc., have been tried in the past, but the effect to retard reflective cracking was not significant. Therefore, it is necessary to find new measures and give them evaluation in the effectiveness to eliminate reflective cracking. Based on the environmental and traffic conditions in Shanghai, three measures(Geogrid, APP and Special Steel Grid)were selected to delay reflective cracking mainly induced by traffic loads and evaluated in laboratory at three tem peratures(-3 , 15^ , 60 ). The result shows that in general three measures can all effectively retard reflective cracking caused by loads; that in particular the special steel grid performed the best effects as compared to geogrid and APP in consideration of the comprehensive effectiveness at three temperatures. Keywords: Geogrid, APP, special steel grid, reflective cracking, asphalt overlay, effectiveness.
