Uji CBR (California Bearing Ratio) pada Tanah Lempung Stabilisasi Abu Marmer dan Biogrouting

Abstract

The existing subgrade for road construction is quite diverse, and sometimes it does not meet the standards for construction subgrade. Repair efforts are needed if the existing land has a fairly low CBR (California Bearing Ratio) value. Stabilization materials for soil improvement can use waste in the form of marble ash, and as a comparison in this research improvements were also conducted using the biogrouting method. The aim of this research is to obtain the effect of marble ash stabilization and biogrouting on the CBR value. The research was carried out through CBR tests on a physical model of soil stabilized with 3-6% marble ash and soil improved using the bacteria bacillus subtilis and bacillus amyloliquefaciens. Tests are differentiated based on the thickness of the stabilized soil, which is 10–30 cm. The research results showed that marble ash-stabilized soil resulted in a better increase in CBR values compared to soil improved using the biogrouting method. CBR values that meet standards for road construction base soils are obtained on soil stabilized with 6% marble ash with a minimum stabilized soil layer thickness of 20 cm.