复杂地质环境下异形交叉暗挖通道开挖数值模拟

Numerical Simulation of the Excavation of Irregularly Crossed Mined Tunnels in Complex Geological Environment

针对城市地铁暗挖通道空间受限且地面沉降控制要求高的问题,文章结合北京地铁3号线朝阳公园站一石佛营站区间隧道工程实例,运用FLAC3D软件模拟分析异形交叉暗挖通道施工不同施工顺序和施工距离对各通道地表沉降变化规律的影响,以确定推荐的施工方案。研究结果表明:各通道施工的先后顺序对地表最终沉降影响不大,但各施工阶段地表沉降变化规律不同;相邻掌子面距离越远对地表沉降的影响越小,当达到一定距离后对地表沉降的影响可忽略不计;交叉暗挖通道施工过程中挑高段隧道施工引起的地表沉降量最大,在挑高段隧道施工时应注意地表变形。

Based on the problems of limited space and high requirements for ground surface settlement control of urban subway mined tunnels,this paper draws on the example of the tunnel project of the Chaoyang Park StationShifoying Station section of Beijing Metro Line 3,and uses the FLAC3D software to simulate and analyze the effects of different construction sequences and distances of irregularly crossed mined tunnels on the changing pattern of the ground surface settlement of each tunnel,so as to determine the recommended construction schemes.The results show that the construction sequence of each tunnel has an insignificant effect on the final ground surface settlement but the changing pattern of the ground surface settlement is different at each construction phase;The farther is the distance between the adjacent tunnel faces,the smaller the influence on ground surface settlement would be,and when a certain distance is reached,the impact on the ground surface settlement is negligible;The ground surface settlement caused by the roof ripping construction of the transverse passage during the construction of the crossed mined tunnels is the largest,and attention should be paid to the deformation of the ground during the roof ripping construction of the transverse passage.