Comparison of Limiting Equilibrium and Finite Element Analysis for Embedded Retaining Walls

Abstract

AbstractA classic part of geotechnical engineering is the design of embedded retaining walls. They comprise of sheet pile walls, secant pile walls, diaphragm walls, and similar and are important part of many civil structures. Embedded retaining walls commonly comprise steel sheet piling or concrete walls, built as diaphragm walls in slurry trenches or using piling methods. The performance and design of embedded walls have been debated extensively by many authors, whilst codes of practice aim to specify design procedures. This paper compares the results of a limit equilibrium approach with the results of finite element method. The finite element analysis was done in PLAXIS code and soil was modeled as Mohr–Coulomb. The soil was modeled as drained type with zero pore water pressures. The analysis of cantilever wall, single propped wall (CMRL-Case study), and multi-prop wall as given in CIRIA SP 95 for sheet pile cofferdams is done and the results were compared. The compared results show that both the limit equilibrium method used for analysis and the finite element approach gives similar prediction of the maximum bending moment. It also shows that the earth pressures in the passive state are matching at the top, i.e., just below the excavated level, but the earth pressures from the Plaxis decreases as it moves toward the toe.KeywordsRetaining wallsDiaphragm wallsEarth pressureFinite elementSoil–structure interaction