Analysis of Micro Pile as Alternative Foundation System for Light Weight Structure on Expansive Soil around Addis Ababa City

Abstract

Most part of Addis Ababa is covered by expansive soil and constructions of structures become increasing due to rapid urbanization. The lightweight structures constructed in this soil show cracking, tilting of window and doors, differential settlement caused by swelling and shrinkages of the soil. Therefore, to minimize such defects, there are different mitigations or remedial measures. The purpose of this study is to analyze and comparison of micro pile foundation system with isolated footing for lightweight structures on expansive soil. The analysis done by considering foundation construction cost and period, and environmental disturbance. Using allowable bearing capacity of soil and ETABS 2016 software to determine point load coming to footing and then both type foundation are designed using the point load. The result showed that construction of isolated footing needs large volume of excavation and takes more construction period in comparison with micro pile. The cost required for construction of micro pile is minimized by 7.79% as compared with isolated foundation. This study definitely answers the question concerning economy and feasibility of micro pile foundation for lightweight structure on expansive soil.