钢支撑对基坑的影响分析—以武汉地铁2号线为例

以武汉地铁2号线机场线盘龙城车站出入口基坑为例，采用围护桩水平位移监测及数据采集方法，分析有无架设钢支撑支护桩深度-位移曲线，探讨围护桩水平位移变化规律. 然后采用有限元软件PLAXIS 2D模拟分析基坑开挖过程有无架设钢支撑支护桩内力和水平位移变化规律，并与现场监测数据相互验证. 由围护结构水平位移的监测数据和数值模拟结果可得，在基坑内架设钢支撑可以减缓基坑偏移速率以及在距围护桩桩底的H/3~2H/3处，偏移量最为明显，偏移量也最大，呈“弓”字型.

Influence of Steel Supports on Deformation of Foundation Pit:a Case of No.2 Subway Line in Wuhan

Taking entrance foundation pit of Panlongcheng station of airport section in line 2 Wuhan Metro System as a case，we employed the horizontal displacement monitoring and data collection method to analyze the depth-displacement curves of the steel supporting and retaining pile and the rules of horizontal displacement of retaining pile. And then we used the finite element software PLAXIS 2D to explore variation law of the horizontal displacement and inner stress of supporting piles in the project of foundation. By comparing the data of field monitoring and simulation，the results show that the installing steel support slows down the displacement’s development rate and the change of development rate is significant at the 1/3-2/3 height from the bottom of the pile，showing a bow appearance.