桩基存在对基坑坑底变形性状的作用分析

Analysis on Deformation Behavior of Basal Heave Considering Pile Foundation

摘要:

基坑开挖时的卸荷，使土体应力场发生变化，引起坑底土体向上隆起。根据土体变形与模量的关系，探讨桩基的存在对土体模量以及基坑坑底隆起的影响。通过有限元ANSYS计算模拟了基坑开挖的过程，得出了有桩基和无桩基时基坑坑底隆起的趋势，讨论了桩距、桩长、桩荷的影响。计算结果与室内模拟试验得出的结果相同，与现场实测结果基本相符。

关键词:基坑;变形性状;坑底隆起;模拟试验;工程桩;立柱桩

Abstract:

The stress field of soils will change and bottom of foundation pit will upheave with excavation unloading. According to the relation between deformation and modulus of soil mass, the influence of pile foundation on modulus of soil mass and basal heave is studied. The process of excavation is simulated by the FEM software ANSYS, the trends of basal heave with or without pile foundation are calculated, and the influence of pile space, pile length and the loading on pile are discussed. The results of calculation are the same to the results of simulation test and basically the same to the field measurement.

Key words:foundation pit; deformation behavior; basal heave; simulation test; engineering pile; upright pile