Performance Evaluation of Full Depth Reclaimed Surface-Dressed Pavement Treated with Cement and Calcium Carbide Residue as Road Base

Abstract

Performance evaluation of Full Depth Reclaimed Surface-dressed Pavement (FDRSP), treated with cement and Calcium Carbide Residue (CCR) as road base was undertaken. Wearing and base courses of a surface-dressed road was scarified and mixed to form FDRSP, which was found to consist of 28.7 % Reclaimed Surface-dressed (RSP) and 71.3% soil from the base course. Laboratory tests were carried out to determine the most economic mixture of FDRSP/cement/CCR that will give a Californian Bearing Ratio (CBR) value of 150%, required for heavy traffic roads. The results showed that the original base course material of the road classified under A-2-5, but when mixed with Reclaimed Surface-dressed Pavement (RSP), the resulting material (FDRSP) classified under A-2-4 according to AASHTO soil classification system. 2% cement and 4% CCR, added to the FDRSP, satisfied the 150% CBR required for heavy traffic roads. From laboratory and field density results for the FDRSP, FDRSP/cement mixture and FDRSP/cement/CCR mixtures, it was observed that more than 95% density can be achieved after 14 days exposure to the traffic load. Field CBR results of the compacted FDRSP/2% cement/4% CCR agreed with the laboratory CBR after 14 days of exposure to traffic load on the road, while the field CBR result of the section with only FDRSP agreed with laboratory value after 7 days, after which the value became higher than the laboratory value