临近基坑条形基础地基承载力减损性状的数值模拟

利用数值模拟技术,参照Terzaghi计算地基承载力的叠加公式,分别按土的黏聚力、基础埋深(超载)和土的自重三个影响因素,估算临近基坑地基极限荷载,给出了不同工况下临近基坑条形浅基础地基承载力系数。通过对极限荷载作用下各工况应力场和位移场动态模拟发现,在基坑开挖深度变化范围内,潜在的滑移面均出现在基坑坡脚附近,大致沿坡脚以上地基土体滑动。并且利用获得的数值模拟结果,对临近基坑地基承载力减损情况进行了分析、讨论。

NUMERICAL STUDIES OF LOSS OF BEARING CAPACITY FOR STRIP FOOTINGS NEAR EXCAVATIONS

Using the numerical simulating technique,the limit loads with various parameters for strip footings near excavations are obtained.As accepted in other proposals,the estimate of the bearing capacity near an excavation is calculated here respectively from the terms dependent on the cohesion,the footing depth(overburden) and the soil weight based on Terzaghi's assumption of superposition.According to the stress and displacement filed simulated within the range of excavation depths,it is found that potential critical sliding surfaces are allowed above-the-toe failures.And further,the characteristics of bearing capacity adjacent to excavations are discussed using the results that obtained in terms of the bearing capacity coefficients from numerical modeling.