摘要
以深圳地铁5号线民治站基坑工程为依托,通过对基坑连续墙水平位移及内力的实测分析,系统研究偏压基坑围护结构位移和内力特征,对围护结构稳定性进行评价。测试结果表明:基坑开挖较浅时,两侧墙体上部发生向基坑内的变形,但受列车及路基偏压影响,紧邻铁路侧墙体位移比远离铁路侧墙体位移大,基坑挖至一定深度后,远离铁路侧墙体上部向基坑外移动,且基坑开挖越深,向基坑外变形越大;相同工序、相同深度条件下,紧邻铁路侧墙体弯矩较远离铁路侧大,紧邻铁路侧墙体弯矩最大值位置比远离铁路侧墙体深;根据偏压基坑位移及受力模式,设计上应对基坑两侧支护参数区别考虑。测试结论可为偏压基坑设计施工提供参考。
Taking the foundation pit of Minzhi station in metro line 5 of Shenzhen city for example,the internal force and deformation characteristics of unsymmetrical-loaded foundation pit？s enclosure structure are systematically studied based on field test;and the stability of retaining structure about the horizontal displacement and internal force of diaphragm wall is evaluated reasonably.The results show that the deformation of top of the diaphragm wall inclined towards the inside of the enclosure structure with shallow excavation depth;and the displacement of the diaphragm wall near railway is larger than that of the diaphragm wall far from railway due to the load from train and unsymmetrical bed.However,the deformation of top of the diaphragm wall far from railway moves towards the outside of the enclosure structure after the excavation depth up to threshold;and the deformation increases with the increasing of excavation depth.Moreover,under the same conditions about construction procedure and excavation depth,the moment of the diaphragm wall near railway is larger than that of the diaphragm wall far from railway;also the maximum moment position of the diaphragm wall near railway is deeper than that of the diaphragm wall far from railway.According to the stress pattern and displacement of unsymmetrical loaded foundation pit,different supporting parameters on both sides of foundation pit should be considered differently.Therefore,the test conclusions can provide reference for the design and construction of foundation pit.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2011年第4期826-833,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
中国中铁股份有限公司科技项目
关键词
地下工程
偏压基坑
连续墙
内力
位移
稳定性
underground engineering
unsymmetrical loaded foundation pit
diaphragm wall
internal force
displacement
stability
