近接地下通道洞桩法车站施工力学特性研究

Influence of Subway station mined in shallow stratum with cavern- pile method on existing underpass

以新疆乌鲁木齐地铁八楼站为工程依托,分析浅埋暗挖车站洞桩法施工对既有地下人行通道的影响规律,采用FLAC3D数值分析软件模拟洞桩法施工过程,研究洞桩法施工过程中地下通道产生的位移值以及内力值变化规律。在横断面内分析洞桩法各工况引起的地下人行通道的沉降量及水平位移值变化规律,得出各个工况产生沉降量、水平位移值的比例,分析各工况下地下人行通道结构内力变化规律,总结对结构内力影响最大的工况及其影响程度,并得出洞桩法施工的安全及稳定性较好,能够较好保护临近建筑物的结论,可为类似的洞桩法近接施工工程提供参考。

Relying on the project at the subway station of BaLou in Urumqi,Xinjiang,this paper analyzed the influence of subway station mined in shallow stratum with PBA method on existing underpass.The cavern-pile construction procedure was simulated using FLAC3D numerical analysis software to study the variations of internal force value and displacement in underpass during the construction.The variations of sedimentation and horizontal displacement in underpass under each condition of the cross sections were analyzed,and the proportions of sedi-mentation and horizontal displacement of each condition were concluded.The change rules of internal force val-ues in underpass under each condition of the cross sections were obtained.Finally,the conditions that influence internal force the most and their occurrences were identified.The results show that the cavern-pile method has a better safety and stability and thus can protect the surrounding buildings.The finding in this paper can also provide useful reference for similar construction projects using the cavern-pile method.