Stabilization of lateritic soil with Portland cement and crushed granite for pavement base courses

Abstract

The aim of this work is to propose reconstituted materials, by cement-based improvement of lateritic gravels and joint cement improvement and lithostabilization, that are technically suitable for use in base courses. The study focused on two (02) different lateritic gravels, LG1 with a fine content of 24% and LG2 with a fine content of 15%. For lithostabilization, 0/25 granite crushed stone was used and the cement used was CEM II/B-LL 42.5. For cement improvement, three (03) cement contents (1%; 1.5% and 2%) were studied, and for joint stabilization, the granite crushed content was set at 10%, with only the cement content varying by 1%, 1.5% and 2%. The mixes were obtained by adding the cement mass calculated from the total gravel mass collected and the cement rate studied to the raw gravel or to a mixture of 90% gravel and 10% granite crushed stone. The results of physical-mechanical tests such as the Atterberg limits, Modified Proctor and California bearing index of stabilized materials were analyzed in comparison with the initial values of raw materials without stabilization. The results show that cement increases the plasticity index but improves the bearing capacity of lateritic gravels better than joint stabilization. However, joint stabilization does improve gravel bearing capacity compared with untreated raw gravel. For use as a base course in accordance with CEBTP specifications [3], in addition to the 10% granite crushed content, LG1 must be upgraded to at least 1.5% cement and LG2 to 1%.