Simulating the Effect of Bagasse Ash Blended With Lime in Stabilizing Weak Subgrade Soil for Flexible Pavement: (Case Study Arbaminch Town, Ethiopia)

Abstract

Expansive clay soil can be found in various parts of Ethiopia, including Arbaminch town. However, because of its inferior quality, the use of expansive soil in road construction is restricted. Therefore, it is crucial to employ a less costly stabilizer to enhance the qualities of locally accessible materials. The overall objective of the study was to simulate a road pavement response model using lime mixed with sugarcane bagasse ash as a subgrade soil stabilizer. To stabilize expansive clay soil, varying percentages (0%–6%) of lime were used. The same procedure was followed with sugarcane bagasse ash, and the sample was then treated with different lime and sugarcane bagasse ash mix ratios of 1%:4%, 2%:3%, 3%:2%, and 4%:1% % due to sugarcane bagasse ash alone added after 4-6 % the CBR value decreased dramatically. A good result was found using 1% sugarcane bagasse ash and 4% lime. The four-day soaked CBR ratio value of subgrade soil for Nachsar campus and Woze kebele was 1.90 % and 2.12%, respectively, but it was increased to 14.50% and 13.40% with the stabilization of 1% sugarcane bagasse ash and 4% lime content. The average of natural and stabilized CBR value from both soil samples was determined in order to conduct finite element simulation with 1% sugarcane bagasse ash + 4% lime, resulting in resilient modulus of 20.77(MPa) and 144.17(MPa), respectively. The decrease in vertical compressive strain and horizontal tensile strain indicates that without stabilization, the natural subgrade layer in this simulation is less stiff.