The finite element simulation and analysis for ∞—shaped super deep foundation pit

摘要

In the field of bridge construction, some anchorage foundation pit with the large plane dimension and the deep excavation depth is found in the construction of the long-span suspension bridge, the mechanics ∞of —shaped super deep foundation pit is more complex among them, and is not analysed in the domestic engineering project. Based on the example of ∞— shaped super deep foundation pit in this paper, the excavation process of the deep pit of south anchorage foundation of a bridge is simulated, the simulation is then analyzed and compared with the field measurements of the foundation pit. The results reveal that the vertical stress and the lateral displacement are obviously reduced by the arching effect ∞of —shaped underground diaphragm wall, the vertical stress is very small compared with the ring stress; the ring stress of the inside and outside underground diaphragm wall is close, and the compressive stress is main; the ring stress of the lining is the ring tensional stress mainly, which reveals that the construction factor has significant influences on the mechanics of the lining. These conclusions provide the theoretical basis and the practical references for the design optimization and the construction control of the similar foundation pit engineering.