Characterization of Wall Deflection and Ground Settlement for Irregular-Shaped Excavations with Changes in Corner Configuration

Excavation usually involves the three-dimensional behavior of the supporting wall and nearby ground as indicated by wall and ground movements. In this study, wall deflection and ground settlement behavior with excavation were investigated, focusing on the effect of excavation shape considering various excavation geometries and corner configurations. For this purpose, the three-dimensional finite-element analyses were performed for both regular and irregular excavation shapes. It was found that the wall deflection and surface settlement both increased with an increasing length-to-width ratio for the regular excavation shape. For the irregular excavation shape with a protruding corner, the corner-wall deflection and surface settlement were smaller than the longer-side wall and the regular excavation shape due to the corner stiffening effect. The location of the maximum wall deflection for the longer-side wall shifted to the longer-strut side when a corner existed. The depth of the maximum wall deflection for the longer-side wall was around 0.6 times of the excavation depth and deeper at the corner wall. The primary influence zone of ground settlement behind the wall was 1.0-1.5 times of excavation depth and larger at the corner side due to the combined wall deflection at the corner.