双排桩支护结构中圈梁空间效应的数值模拟分析

针对深基坑双排桩支护结构中圈梁的空间效应问题,利用FLAC3D模拟计算一深基坑双排桩支护工程在设置圈梁的情况下,其不同位置处桩顶位移与弯矩变化.结果发现:基坑坑角的桩顶位移明显小于中部桩顶位移,越到中部桩顶位移越大;将计算结果与现场实测资料对比表明,两者变化规律具有较好的一致性.研究表明,支护排桩与圈梁之间有较好的协同作用,圈梁对支护桩的变形和内力均有一定的影响,限制了排桩的位移和弯矩,越靠近基坑坑角其空间效应越明显.在双排桩支护结构体系设计中应考虑圈梁的空间效应,为优化设计提出建议.

Numerical Analysis of Ring Beam's Spatial Effects in Retaining Structure with Double-Row Piles

The spatial effects of ring beams in retaining structure with double-row piles for a deep foundation were investigated. The software of FLAC3D was employed to study the tip displacements and moments of the piles at different locations in retaining structure with double-row piles and ring beams. Numerical results show that the tip displacements of pile at the corner are much less than the ones in the middle. The maximum tip displacement is located at the piles in the middle. Compared with the on-site measured data, above result match the test data very well. It is also found that the retaining structure with row piles has better synergistic reaction with ring beams. The deformation and internal force are affected by ring beams. The displacement and moment could also be limited by ring beams. Therefore, it is proposed that the spatial effect should be considered in the design of retaining structure with double-row piles.