Strengths of marginal lateritic soil stabilized with biomass ash and alkaline solution

Abstract

This research investigated the improvement of marginal lateritic soil stabilized by biomass ash and alkaline solution. Biomass ash was a by-product of a power plant in Songkhla province. The alkaline solution used in this study was sodium hydroxide (NaOH). The marginal lateritic soil/biomass ash ratio of 70:30 and NaOH contents of 0, 5, 10, 15, and 20% by optimum water content were used. Unconfined compressive strength (UCS) and indirect tensile strength (ITS) of specimens at a curing time of 7 days were evaluated. It was found that UCS and ITS of marginal lateritic soil stabilized by biomass ash and alkaline solution increased as NaOH content increased. The maximum UCS and ITS of marginal lateritic soil stabilized by biomass ash and alkaline solution were 683.25, 697.15  and 342.25, 365.67 kPa at NaOH contents of 20% by optimum water content.