铁路轨道下盾构施工所致地面沉降的数值模拟

3D Numerical Modeling of Ground Settlements Caused by Shield Tunneling Across Multi-tracks of Railway

摘要:

以天津津滨轻轨天津站站——七经路站盾构施工区间工程为对象,采用三维有限元方法,对在多条铁路轨道下长距离盾构掘进过程引起的地表变形进行数值模拟.根据模拟结果,详细分析盾构穿越导致的沿盾构方向和垂直于盾构方向的地表沉降,得出盾构施工各阶段的地表沉降规律,研究盾构掘进对地表的扰动范围,分析先施工隧道和后施工隧道对地表沉降的贡献差异,并探讨对铁路荷载的影响.计算结果与监测结果吻合较好.

关键词:铁路轨道; 盾构施工; 地表沉降; 三维有限元; 数值模拟

Abstract:

Based on the bid-section of Binhai mass transit from Tianjin Station to Qijing Road Station,3D-FEM is put forward to simulate shield tunneling long distance under multi-tracks of railway.According to the simulation results,settlement of ground surface along and perpendicular to the shield tunnel are analyzed in detail,the discipline of ground surface settlement in different driving stages is uncovered; the disturbance area of ground and the settlement ratio dedicated by first tunnel and second tunnel are studied,the function of railway load in causing ground displacement is also discussed.The results fit well with monitoring data and can be used as a reference for similar projects.

Key words:railway track; shield tunneling; ground settlement; 3D-finite element method; numerical modeling