为研究基坑开挖时的变形、稳定性及对坡顶建筑物的影响,以实际工程为例,运用数值模拟分析方法,对含有软弱夹层的顺层岩质基坑边坡在直立开挖与支护过程中的位移场、应力场及对坡顶建筑物影响进行了动态模拟分析。研究结果表明:开挖过程中,岩体卸荷引起变形,支护结构可以限制变形的发展,开挖面处岩体失去原有限制发生卸荷回弹,使得边坡顶部和靠近开挖面处出现拉应力集中区,层状岩体的软弱夹层处会产生较大的剪应力,并随着开挖加深而增大;开挖后边坡顶部已建挡墙附近应力消散,坡顶产生不均匀沉降。
To explore the deformation and stability of foundation pit slope and their influence on the buildings at the top of slope during excavation, a practical engineering is analyzed to numerically simulate the displacement and the stress field of rock slope containing soft interlayer during excavation and supporting process, and their influences on the buildings at the top of slope. The results show that during excavation, the trend of the deformation, which is caused by the unloading of rock mass, can be limited with supporting measures being taken. Unloading rebound occurs in mass in the face of the excavation because of restrictions lost, which leads to high tensile stress areas in the top of the slope and near the excavation surface. Larger shear stress that produces in the structure face increases with the deepening of slope excavation. After excavation, the stress near retaining wall established in the upper slope dissipates, and the uneven settlement appears at the top of slope.