摘要
文章以沈阳地铁中街站大跨度隧道工程为研究对象,应用FLAC3D计算软件,对复杂条件下浅埋暗挖大跨度隧道引起的地表沉降变形特征进行了数值模拟。根据洞桩法施工开挖方案,紧密结合工程实际,将动态施工开挖过程划分五个工况进行模拟,分析各施工工况对地表变形的影响和分布规律,并按工程信息化施工要求事前将预测数据提供施工单位,以指导施工控制地表沉降。模拟结果表明,采用洞桩法开挖施工过程中,对地层土体扰动较大,明显影响隧道中心附近地表变形的步序是小导洞开挖和初期支护扣拱施工阶段,约占最终沉降量的70%;而其他步序影响较小。最终,地表沉降在隧道横向分布呈"W"形态。模拟结果与现场监测数据具有较好的拟合性,表明利用数值分析方法预测大跨度隧道施工期地表沉降是可靠的。
Using the large-span tunnel at the Zhongjie station of the Shenyang subway as an example, a numerical simulation of the characteristics of surface settlement induced by the construction of a bored tunnel was performed us- ing FLAC3D finite element software, which divided the construction into five cases and analyzed the impact of con- struction cases on surface settlement and distribution law and provided the predicted data to the contractor. The re suhs show that the disturbance to the soil mass is obvious during the cavern-pile construction and the settlements dur- ing the excavation of the small pilot tunnel and arching of the primary support at the crown amounted to 70% of the to tal settlements. The final surface settlement is in is a ＂W＂ shape in the transverse direction. The simulation results fit well with the field observations
出处
《现代隧道技术》
EI
北大核心
2012年第6期88-92,138,共6页
Modern Tunnelling Technology
基金
水沙科学与水利水电工程国家重点实验室开放研究基金资助课题(sklhse-2011-B-05)
国家自然科学基金资助项目(51074042)
关键词
地铁车站
洞桩法
地表沉降
数值模拟
Subway station
Cavern-pile method
Surface settlement
Numerical simulation
