土岩复合地层深基坑开挖引起地表位移特征与规律研究

Study on characteristics and laws of ground surface displacement caused by deep foundation pit excavation in soil rock composite strata

针对土岩复合地层条件下,地铁车站深基坑开挖引起地表位移对地面重要建筑物产生影响的问题,以乌鲁木齐地铁1号线二道桥车站为研究对象,研究了土岩复合地层深基坑开挖引起地表位移的特征和规律。首先,明确了基坑周边的工程地质概况;其次,利用MIDAS GTS NX软件对在土岩复合地层下无支护基坑的开挖进行了数值模拟;再来,分析了现场实施横撑隔离联合支护基坑开挖所引起的地表位移监测数据,与模拟基坑未支护产生的位移结果作对比,以此评价基坑联合支护的实施效果;最后,总结了土岩复合地层下基坑开挖引起周边地表位移特征与规律。该研究成果可为乌鲁木齐以及其他地区类似工程的设计与施工提供参考,对防止深基坑开挖发生事故、资源浪费具有重要意义。

Aiming at the influence of the ground surface displacement caused by deep excavation of subway station on important ground buildings under soil rock composite formation condition, taking Erdaoqiao station on Urumqi Metro Line 1 as the research object, the characteristics and laws of the surface displacement caused by deep excavation in complex rock soil strata are studied. Firstly, the engineering geological conditions of surrounding ground station aremade clear. Secondly, the MIDAS GTS NX software is used to simulate the excavation offoundation pit without supportin soil rock composite stratum. Again, the monitoring dataof surface displacement caused by the excavation of the foundation pit withimplementation of combined support oftransverse support isolationat siteare analyzed, and the data are compared with the displacement results caused by thesimulated foundation pit excavation without support. Finally, the displacement characteristics and laws of thesurrounding ground surface caused by theexeavation of foundation pit in soil-rock compositestrata are summarized. The results of the study can provide reference for design and construction of similar projects in Urumqi and other areas ,whichis of great significance to preventing the accidents in deep excavationand the waste of resources.