Evaluation the Swelling Properties of Expansive Soil mixed with Rice Husk Ash (RHA) and Silica Fume (SF)

Abstract

Abstract. Utilization of waste materials in agriculture products reduces the technical and environmental problems of plants wastes. Although rice husk ash (RHA) is a valuable admixture for concrete and soils, only about 5% of the total available RHA are used for enhancing concrete properties and improvement of swelling properties of expansive soil. However, the utilization rate of it is steadily increasing every year. Newly developed admixture allow decreasing of swelling properties of expansive soil by incorporating of rice husk ash as waste material and silica fume (SF) which denote RHA-SF. This study presents an experimental study on expansive soil mixed with additives in different ratios. The work involves three types of mixes the first consisted of four different percentages of RHA without SF. The second trial used four different percentages of SF without RHA. The last mixes included sixteen different percentages of mixed RHA and SF. The research concluded that 7.5% of rice husk ash and 20% silica fume are the optimum amount of additives to reduce swelling properties of expansive soil.