深基坑开挖对周围土体与地铁隧道变形影响分析

Analysis of influence of deep foundation pit excavation on deformation of surrounding soil and subway tunnel

以杭州市某临近地铁隧道深基坑工程为例,对在不利工程条件下的深基坑开挖对周围土体水平位移变化规律和既有地铁隧道变形规律进行了分析。分析结果表明,基坑周围土体水平位移随着开挖深度的增大而增大;基坑周围既有隧道的道床水平位移和竖向位移都会受到开挖深度的影响,距离基坑距离越近受到的影响越明显;对于临近地铁隧道的深基坑工程,采用适当的支护体系仍能较好控制隧道变形。研究结果为类似工程提供了参考依据。

Taking a deep foundation pit project of a nearby subway tunnel in Hangzhou as an example, the variation law of horizontal displacement of surrounding soil and deformation law of existing subway tunnel under unfavorable engineering conditions are analyzed. The analysis results show that the horizontal displacement of soil around the foundation pit increases with the excavation depth increasing. Both horizontal and vertical displacements of existing tunnels around the foundation pit are affected by the excavation depth, and the closer the distance from the foundation pit is, the more obvious the effect is. For the deep foundation pit near the subway tunnel, the deformation of the tunnel can still be well controlled by the appropriate support system. The research results of this paper provide a reference for similar projects.