Effect of Zeolite Mixture Percentage on the Free Compressive Strength Test Value of Clay Soil in Pulo Padang Village in Mandailing Natal Regency

Abstract

High plasticity clay soils which are often encountered in field construction work have low bearing strength and large volume changes (shrinkage expansion). Soil will expand when the pores are filled with water and will shrink in dry conditions. This makes the soil unstable, and it is unable to support a building construction. Therefore, soil improvement efforts are needed to increase this soft clay soil. Soil stabilization is a soil improvement effort to strengthen soil that has low bearing capacity. In this research, the soil stabilization method is carried out using mixed materials to reduce or eliminate the unfavorable properties of the soil to be used. To improve the quality of the soil, zeolite is used. In its utilization, zeolite is able to withstand high heat and can increase the bearing capacity of clay soil. This research was conducted to determine the effect of zeolite addition on the compressive strength value of clay soil. In this study, the percentage of zeolite mixture used was 0%, 2%, 4%, 6%, 8%, and 10%. Based on the research results, the addition of zeolite mixture percentage in clay soil can increase the compressive strength value of the soil where the compressive strength value of the soil increases. However, the increase in soil compressive strength value occurred only until the addition of zeolite by 8% with a compressive strength value of 12.208 kg/cm2. At the time, at the addition of zeolite at 10%, the compressive strength value of the soil decreased to 9.928kg/cm2. Thus, the addition of zeolite can increase the compressive strength value of soil at the maximum addition limit of 8%. So, zeolite can be used as an alternative material for soil stabilization for subgrade layers. Keywords: Clay, Stabilization, Zeolite, Soil compressive strength