Numerical study on asymmetric excavation-induced supporting structure effect of ∞-shape super deep foundation pit

In this paper, we aim at obtaining the effect of asymmetric excavation-induced supporting structure for ∞-Shaped super deep foundation pit, including the deformation law and the plastic zone of the soil outside the structure. Based on the example of ∞-Shaped super deep foundation pit for South Anchor of the Fourth Nanjing Yangtze River Bridge construction, the full three-dimensional finite element model was used to simulate the south-north asymmetric excavation of the whole foundation pit. Interaction between the supporting structure and the soil had also been taken into account in calculation. Compared with symmetric excavation, the results indicate that asymmetric excavation has little influence on annular concrete diaphragm wall and plastic zone distribution, however, the partition shows an obvious curve to the deeper side. Excursion of the whole supporting structure may occur during asymmetric excavation.