城市建筑边坡稳定性有限差分法数值模拟分析

A finite difference method simulation for stability of building slopes in urban areas

基于理想的弹塑性本构模型和莫尔库伦准则,运用有限差分法、岩体力学理论及强度折减原理,对城市建筑边坡在坡顶荷载作用下不同开挖阶段的应力、变形及边坡的稳定性问题进行了数值模拟分析。分析结果表明:由于坡顶荷载作用,边坡潜在滑动面比理论值倾斜度高,坡体出现两个明显的应力集中的破坏带,一个在开挖的坡脚,一个在已建建筑的外侧,且在坡顶荷载以下,位移趋势出现突变,迅速增大,数值模拟很好反应了建筑边坡在开挖及支护的各个阶段的安全稳定状态,模拟显示,此加固措施效果较好。

We simulate the stress, displacement and the stability of an urban building under load on the top of a slope during different excavation stages. Our research is based on a perfectly elastic-plastic constitutive model and applied the Mohr-Coulomb yield criterion, the finite difference method, the rock mechanics and the strength reduction principle. The results indicate that the slope angle of the potential surface of sliding is higher than its theoretical value, and that there are two rupture zones due to obvious stress concentration-one appears at the toe of a slope and the other at the outside of the building. The displacement trend changes abruptly and increases rapidly as a result of the slope top load. The safety stability status of the slope of a building is well indicated by the numerical simulation during every stage of excavation and support. The results show that the strengthening measure is an effective method.