Development of soft soil improvement scheme for lateral stability of railway bridge abutment

Abstract

This paper describes the development of a design scheme of soft ground improvement using Sand Compaction Pile (SCP) around the abutment of Railway Bridge. Subsoil at studied bridge abutment location was thick soft clay underlain by medium dense to dense sand layers. It was found that lateral movement of pile supported abutment was 100 mm without subsoil improvement. To control excessive lateral deformation of abutment, soft clay later need to be improved. SCP was considered as the ground treatment scheme. 3D finite-element simulation was conducted to optimize replacement ratio and extent of ground treatment. 3D finite element parametric study shows that lateral displacement of the abutment is within allowable limit when the subsoil is improved using SCP. It was also concluded that SCOP treatment needed to be extended 5 m towards the river side, 5 m surrounding the pile cap and 10 m in land side for optimum effect of ground improvement.