深基坑分层分段放坡开挖临时支撑架设滞后问题研究

Study on the Lag of Temporary Support in Layered and Segmented Excavation of Deep Foundation Pit

以武汉地铁阳逻线的车站基坑工程为背景,应用FLAC3D数值计算软件对基坑分层开挖与逐级架撑过程进行模拟分析。通过对比几种支撑架设滞后方案的计算结果,总结了开挖面支撑架设滞后时,围护结构变形及钢支撑轴力的变化特征。结果表明:滞后支撑的数量相同的情况下,开挖面横排钢支撑架设滞后对基坑受力变形的影响最小,纵列钢支撑架设滞后影响最大;通过调整已架设钢支撑的轴力来控制缺撑区域的变形是可行的。

Based on the excavation of an underground metro station in YangLuo line of Wuhan Metro,this paper employs the numerical analysis software FLAC3 D to simulate the complex staged excavation process.By comparing the results,the research draws a general conclusion about the deformation characteristics of retaining structure and the change of pre-stress on steel support.The analysis results indicate that:the lack of horizontal steel support has the least influence while the lack of vertical steel support is the worse with the same lack of steel support.Despite its limited effectiveness,but the numerical simulation also show that,it is feasible to control the deformation of the retaining structure by adjusting the pre-stress on completed steel support.