车辆动载作用下地下通道基坑稳定性研究

The Stable Study of Underground Tunnel Foundation Pit under Vehicular Dynamic Load

隆祥街地下通道位于武汉市汉阳区龙阳大道与隆祥街的交汇处,地标建筑物多且近,路面交通十分繁忙,地下通道基坑在开挖时会产生基坑坑壁的水平位移和竖直沉降,造成基坑失稳,而路面车辆动载是造成基坑坑壁失稳的重要因素之一。根据数值分析相关理论,建立地下通道基坑模型,采用FLAC3D有限差分法软件对开挖进行数值模拟,对坑壁监测点的数值计算结果与实际监测结果进行对比,判断车辆动载数值模拟函数是否可行,以及基坑在车辆动载作用下的稳定性情况。在半波正弦数值模拟函数的作用下,坑壁监测点的数值计算结果与实际监测结果在误差允许范围内,故采用半波正弦函数对车辆动载进行数值模拟的方案是可行的,而且基坑是稳定的。

The underground engineering of Longxiangjie Street is located at the intersection which lies across Longyang Avenue and Longxiangjie Street in Hanyang district,Wuhan.There are many landmark buildings that are located in short distance there.The traffic is also very busy.When underground tunnel is excavated,the side-wall of foundation will produce horizontal displacements and vertical displacements.This may lend the failure of foundation.Vehicular dynamic load is one of the most important reasons which cause the failure of foundation.Underground engineering model is established on the basis of numerical analysis theory.The excavation process of the model is simulated by using finite difference software FLAC3 D.Comparing numerical calculations with monitoring data,you can estimate vehicular dynamically simulative function is workable or not.Besides it,you can also judge the foundation is stable or not.When the foundation pit is affected by a half sine wave load,numerical calculations of the side-wall are similar to monitoring data of the side-wall.So the vehicular dynamic load can be replaced by a half sine wave load and the foundation is stable.