Settlement Analysis in Deep Excavations by Top-down Construction in Soft Soils using FEM

摘要

A series of three-dimensional finite-element analyses have been made to simulate deep excavation in soft soils with an elasto-viscoplastic constitutive relationship using top-down construction (TDC). For a particular substructure geometry and certain ground conditions, the settlement variation due to change of construction sequences and/ or pillar pile supporting system, is especially presented and discussed. On the whole, with TDC the settlement of basement floor is spherical, and it develops as construction progresses. In addition, different construction sequences obviously affect the settlement of pillars and walls, and different pillar pile supporting system has influence on the magnitude and distribution of differential settlement between pillars and walls.