Evaluation of cement stabilised residual soil on macro- and micro-scale for road construction

Abstract Lateritic soil is a kind of residual soil widespread in tropical countries. This soil usually possesses acceptable engineering properties to be laid under the construction projects. However, it needs treatment for transportation infrastructure such as railway and road subgrade and embankment, particularly when it is in fine-grained form. Thus, cement, one of the very common stabiliser agents in soil stabilisation, was selected to study its influence on lateritic soil at macro- and micro-levels. In order to achieve this goal, UCS, durability, FESEM and EDX tests were conducted. The results obtained indicate that the UCS increase occurs with an increase in cement content and curing time. It was also found that the shear modulus increases with cement content and curing time. The durability test results disclosed that 3% cement is not enough for soil stabilisation when used for projects in the areas subjected to cyclic wetting-drying cycles. The durability test results revealed that the UCS decreased for specimens treated with 6% cement, while on the other hand, the UCS increased for samples treated with 9% and 12% cement. The FESEM results revealed that the soil micro-structure changed with the addition of cement and curing time. The EDX results presented the chemical elements change upon adding cement and increasing curing time. Overall, it was found that cement-stabilised residual soil can be used for road construction. However, the cement percentage needed to stabilise residual soil differs depending on the standards