Modified Design Methodology for Cantilever Sheet Pile Walls Embedded in Cohesive Soils with Surcharge: Determining Pivot Point Position and Penetration Depth

Abstract

Effective sheet-pile wall designs are increasingly important due to the growing need for deeper excavations caused by urbanization. Cantilever Sheet pile walls (CSPWs) are among the most commonly used retaining systems for excavations reaching depths of up to six meters. While CSPWs have been widely studied under both static and seismic circumstances, their performance when embedded in clay has not been sufficiently explored. To address the identified gap in the literature, a detailed and systematic design procedure is developed for CSPWs in cohesive soils, particularly in the presence of infinite, uniform surcharge loads. The main aim of the present study is to formulate the equations to find the position of pivot-point and penetration depth with respect to the soil properties, magnitude of surcharge, and excavation height of CSPW. The design framework is based on the premise that the sheet pile wall exhibits rigid-body rotational movement about a pivot point near the toe under a specified displacement mode. The analysis evaluates the lateral soil pressure distributions on each side of the wall and determines the required embedment by concurrently satisfying horizontal force and moment equilibrium conditions. The proposed study is validated by comparison with published results. It is observed that for a surcharge of 50 kN/m², increasing excavation height from 3 m to 6 m can increase the required penetration depth by more than 250% for dense sand backfill, while higher clay cohesion significantly reduces embedment demand. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2026.