Gati Sri Utami
Department of Civil Engineering, Institut Teknologi Adhi Tama Surabaya, Indonesia
E-Mail: [email protected]
ABSTRACT
Lapindo mud containing silicate (SiO2) that can function as a filler and lime (CaO ) as a binder between the particles . Previous research in the use of these materials, may be used as, a substitute material of cement, to mix concrete manufacture. While in this study, Lapindo mud is used as, a substitute material lime to stabilize clay soils containing salt. Soil samples were taken from the area Sumenep then mixed with mud Lapindo 10%, 20%, 30%, 40%, 50%. Results of this study, up to 50% concentration slurry liquid limit value decreased 16.67 % and plasticity index, 73.73 % decline of the native land. Test compaction up with a mixture of 40%, the solid based on the increase of the value of γdmax, γdmax
native land at 1.42 kg / cm3 be 1:56 kg / cm3, which means an increase of 11.43%. CBR test up to 30% Lapindo mud mixture , 9.02% CBR value is including the category of value CBR is good enough as a land base and an increase of 44.55
% from the original soil . Direct shear test Lapindo mud up to levels of 40%, the value of the shear stress increased by 40.25% of the original soil. Free press test until the Lapindo mud levels of 40%, the value of free compressive stress 2.03kg / cm2 very rigid categories and an increase of 39.04% from the original soil. And to test free swelling up to levels of 50% Lapindo mud, with a 24 -hour immersion, the value of development decreased by 63.64%. So in general it can be said that the levels of Lapindo mud more than 50% effective in stabilizing the clay in Sumenep area to reduce the potential for
development, while raising the level of Lapindo mud carrying capacity is a maximum of 40%.
Keywords: lapindo mud, stabilization, salt, expands, carrying capacity