EXPERIMENTAL STUDY OF SOFT SOIL STABILIZATION USING ZEOLITE ON DRY-WET CYCLES

Soft soil was so vulnerable to changes in moisture content, affecting its mechanical properties which could lead to deterioration of a structure. This situation happens mostly in tropical climate areas where the moisture content of the soil fluctuating all year long during rainy and sunny season. Soil stabilization become one of engineer choices to overcome this situation. Mostly, cement used as a binder agent to increase the dry density of the soil, reduce its permeability and giving more durability against damage done by water. In this research, natural zeolite used as substitutive for cement. Soft soil mixed with varied zeolite content, namely 3%, 6% and 9% compared to the dry weight of the soil in each optimum proctor condition. After the CBR and UCT specimens was remolded according to ASTM D-1883 and ASTM D-2166, the samples were then treated using Dry-Wet Scenario. The whole soaked and un-soaked process consist of 3 wet/soaked phase and 3 dry/un-soaked phase for each specimen. The result of the tests showed that natural zeolite could prevent swelling and mechanical value loses due to its pozzolanic properties. The CBR and UCS value showed that by adding more zeolite, the more stable and durable the soil became. At the initial condition, zeolite already increased the soil's CBR and UCS value. This result showed that zeolite might be an alternative to cement in soil stabilizing purposes and might be the proper soil stabilizing agent, especially in tropical-climate areas with fluctuating moisture content of the soil due to rain and sunny season