Effects of Mechanical Stabilization on Expansive Soil using Ambo Sand Stone as Subgrade Material

Abstract

Expansive soil is a clay soil that changes its volume depending on the seasonal variation of the moisture.  These types of soil create serious problems to the civil engineering structures.  To improve this different researchers found different method, among this mechanical stabilization using locally available materials are the one.  Therefore these study was done on the stabilizing the expansive properties of soil of Ambo city by locally available material.To perform this study soil was taken from five (5) pits, on 15km under construction road in Ambo city and Ambo sand stone from Sankale Faris. This study was done by mechanically mixing the ambo sand stone with expansive soil by percent. The mix ratio was prepared by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% for ambo sandstone of mass of soil and the engineering properties of pure expansive soil and mixed soil with sand stone were done accordingly.The lab result indicates that as sand stone increases in the mixes, the liquid limits, plastic limits, shrinkage and free swell of treated soil decreases, the CBR increases. The UCS increase as the sand stone percentage increases to 60% and then decreases.  Hence, the addition of this stabilizer decreases the plasticity properties of the treated soil. Therefore, the optimum mix ratio was attained at 60% ambo sand stone to stabilize the soil. The mixes of ambo sandstone changes the geotechnical properties of the natural soil and makes this soil to be suitable for subgrade construction.

Keywords: Geotechnical properties, Sand Stone, Stabilization, Subgrade, Swelling

DOI: 10.7176/CER/16-1-02

Publication date: January 31^st 2024