PENGARUH ABU VULKANIK SEBAGAI BAHAN STABILISASI TANAH UNTUK LAPIS SUBGRADE

Abstract

Subgrade is the base ground surface or ground excavation or compacted filled surface soil and form a base surface for placement the section of other pavement. The strength and durability of pavement construction depends on the characteristic of soil bearing capacity. The better spec for the subgrade soil, the value of soil bearing capacity increasingly great. This study aims to evaluate how much influence the use of stabilization material (volcanic ash) with varying levels and constant mixture of lime on the soil samples to the value of consistency limits, dry volume weight- moisture content relation and review of the CBR value. The research was carried out by mixing native soil with lime stabilization material constantly weight percentage of 5% and volcanic ash that varied by 5%, 10%, 15%, 20%, 25% and 30% of the soil dry weight. To determine the maximum density and the value of CBR, researcher use standard proctor device and CBR testing laboratory and Atterberg limit testing to determine the limits of consistency. These tests concluded that the soil samples in the category of poor clay soil as subgrade material. After stabilized using volcanic ash and lime is seen that there is an increase in the carrying capacity of the power, that�s increasing the volume of dry weight, decreasing of soil swelling and increasing in the value of CBR. However, the CBR value that less than 5% of the soil mixture experiment results are categorized into the soil criteria with a low CBR value