IMPROVEMENT FOR SUBSOIL BY CEMENT COLUMN – A CASE STUDY IN THAILAND

For road construction on soft clay, controlling of the settlement is important. In Thailand, the allowable post-construction settlements are 0.25 m for normal section. There are several methods to reduce the construction settlement. Improving soft soil by cement column is one of the methods whereby the soil is mechanically blended with cement to form soil-cement column. This method is widely employed for highway project because it can rapidly improve of soil strength and also relatively safe to the environment. The cement column is adopted to serves as an excellent foundations, and resist stability during construction process. It has recently been used to improve the strength and deformation characteristics of these soft clays. For the abovementioned reasons, a comprehensive laboratory testing programme was carried out in order to study the effect of inclusion of cement on physical and engineering behaviour of a soft clay. A series of tests was carried out by varying proportion of Portland cement and soft clay. In this paper, the physical characteristics, inde