Evaluation of Stability of Embankment Constructed on Soft Consolidating Soil with Lime–CFG Composite Column System

Abstract

AbstractEffectiveness of providing lime and CFG composite column system on the safety factor of embankment constructed on consolidating soil is studied at different time intervals during consolidation of foundation soil. The effectiveness of providing composite column system is compared with the effectiveness of providing only lime or CFG columns. In addition, the effectiveness of composite column system on settlement of foundation soil and consolidation process is also investigated. Embankment, foundation soil and columns are modeled using finite element method. Numbers of trial surfaces with different center and radius are generated at each time interval and the critical surface is selected to calculate the safety factor using the effective stresses obtained by finite element analysis. From the study, it is concluded that provision of lime or CFG columns, either individually or in combination, reduces the settlement and improves the safety factor. However, the most effective type of columns and their arrangement to reduce the settlement may not be the most effective to enhance the safety factor and hence, the type of columns and their arrangements has considerable influence on the purpose for which columns are provided.