Durability study of expansive clay treated with bagasse ash and cement slag

Abstract

The increase in large amounts of commercial wastes like bagasse ash and industrial slag year by year becomes a serious issue of disposal. It is indeed to utilize such wastes effectively for sustainable development in construction practice. The type and amount of additives play a major role in the stabilization process. The material should be select based on different properties and chemical composition. This study shows the effect of industrial waste Portland cement slag (CS) with a combination of bagasse ash (BA) to stabilize expansive clay. Index properties, swell and strength characteristics have been checked for different proportion mixes (BA–CS) to find optimum mix using the best possible proportion. The optimum mix obtained is 77.5% clay + 15% BA + 7.5% CS, which minimizes the swelling characteristics and converts it into non-swelling soil with time. The unconfined compressive strength reported as 780 kN/m2 increases almost three times after 28-day curing period as compared to natural clay. Soaked CBR of the optimum mix of 13.2% shows almost four times. Untreated and optimum mix samples have been tested for the durability of the mix under the wetting–drying cycle cause due to the effect of seasonal variation. Optimum mix sustains for more number of cycles as compared to untreated clay. From the study, the proposed mix may be suitable to treat expansive clay to construct a lightweight structure like pavement on it.