Numerical Analysis for the Stability of Over-Length Trench Wall Based on a Novel Pre-Supporting Excavation Method

Abstract

Building enclosure and supporting system has been widely used for the construction of soft soil foundation. To improve the deformation of envelope system and stratum, this paper presents a novel pre-supporting excavation method (PEM). Unlike traditional construction methods, the new method proposes supporting system be installed completely before excavation and one of the key problems is the stability of over-length trench supported by slurry. Aiming at the stability analysis, this paper does an in-depth research by a numerical simulation analysis and a model of slurry-filled trench wall in the actual excavation environment is analyzed based on the elasto-plastic finite-element method (FEM). Various factors influencing on the stability of trench wall and the settlement of ground surface are considered, especially the groundwater as an important point is of key consideration. The analysis results show that the stability of over-length slurry trench could be ensured in the condition of dewatering under the bottom of foundation pit.