Effects of sulfate attack under wet and dry cycles on strength and durability of Cement-Stablized laterite

Abstract

The designed cement content for laterite soil cement base or subbase for road construction can be estimated from the unconfined compressive strength (UCS) of the compressed cement-stabilized laterite soil sample. However, at the actual construction site, several factors such as sulfate and flood adversely affect the strength and durability of the soil cement. Consequently, the cement content estimation under a normal circumstance may not be sufficient. This research aimed to investigate the effects of wetting and drying cycles (w-d cycles) and sulfate-soaked cycles on the strength and durability of cement-stabilized laterite. The result indicated that the 4 % cement content is suitable for the laterite stabilized cement. After 12 w-d cycles, the strength loss of the sample soils soaked in water and in sulfate were 44 % and 55 % respectively. The durability index (ID) of both sample soils decreased with the increase in the w-d cycles. For soil cement base soaked in water and sulfate, the durability index should be lower than 0.88 or the weight loss should not exceed 12 %. The results also indicated that for practical propose, the normalized strengths under wet and dry cycles were related by a linear relationship for the range of tested cement content, water content, and curing periods. This relationship is very useful for the calculation of the desired strength from the estimated optimal cement content for the soil cement base mainly focusing on the durability against the effects of w-d cycles soaked in water and sulfate at any repeated cycles.