软弱地层狭长深基坑开挖对邻近建筑变形稳定性分析——以成都30号线玉石站为例

Analysis of Deformation and Stability of Adjacent Buildings Caused by Excavation of Narrow and Long Deep Foundation Pit in Soft Stratum:Taking Yushi Station of Chengdu Line 30 as an Example

深基坑工程建设时会对周边建筑产生一定程度的影响。为更加深入及准确地分析深基坑开挖过程中自身结构变形及对邻近建筑物的变形规律,依托成都30号线玉石站狭长深基坑工程,通过理论分析结合数值仿真和现场全过程监测手段系统研究基坑开挖对自身结构及周边环境的影响。结果表明,邻近建筑物深基坑开挖需要提高变形控制标准以降低施工期间对周边建筑物的影响;建筑物旁侧注浆加固一方面降低了施工期间建筑物的沉降,另一方面也减小了基坑围护结构的侧向位移及周边地表沉降;通过对建筑物沉降进行全过程监测结果表明建筑物变形呈现先上升后下降趋势,这与前期注浆抬升及后期未及时跟进注浆联系紧密。上述研究成果可为类似工程提供借鉴。

The construction of deep foundation pit engineering will have a certain degree of influence on the surrounding buildings.In order to analyze the structural deformation of deep foundation pit and the deformation law of adjacent buildings in the process of deep foundation pit excavation more deeply and accurately,relying on the narrow and long deep foundation pit project of Yushi Station of Chengdu Line 30,the influence of foundation pit excavation on its own structure and surrounding environment was systematically studied by means of theoretical analysis,numerical simulation and on-site whole process monitoring.The results show that the deep foundation pit excavation of adjacent buildings needs to improve the deformation control standard to reduce the impact on surrounding buildings during construction.On the one hand,the side grouting reinforcement of the building reduces the settlement of the building during the construction period,on the other hand,it also reduces the lateral displacement of the foundation pit retaining structure and the surrounding surface settlement.The monitoring results of the whole process of building settlement show that the deformation of the building shows a trend of rising first and then falling,which is closely related to the early grouting uplift and the late failure to follow up the grouting in time.The above research results can provide reference for similar projects.