Ground Movements Caused by Diaphragm Wall Installation

Two-dimensional numerical analysis has been conducted on a case history on ground movements caused by installation of diaphragm walls in soft ground. The trenching was supported with bentonite slurry. Inward ground movements occurs due to the horizontal earth pressures imbalance. The approach of replacing the unit weights of the soil in the trench with that of the bentonite slurry has been adopted. While the slurry supporting the trench has virtually no stiffness, the trench was mainly resisted by the adjacent ground between the primary panels, the concrete wall and gravel infill. This study provides an approximation on the 2-Dimensional analysis on wall trenching. The analysis shows that the surcharge load and the groundwater pressures would affect the ground movements induced by diaphragm wall installation.