【摘要】 深基坑开挖时周围土体的卸荷作用将引起邻近既有地铁隧道的变形,对其正常使用产生影响,隔离桩的位置控制隧道变形的效果值得研究。基于杭州市某房建地下室基坑工程采用隔离桩保护邻近既有地铁隧道的工程案例,采用ABAQUS有限元软件进行数值模拟,建立二维模型对隔离桩在不同位置条件下隧道的变形进行了分析。研究结果表明:基坑开挖最终引起隧道下沉约3.1 mm,隧道向靠近基坑方向水平位移约1.7 mm,数值模拟计算结果与现场实测数据的相关规律吻合;隔离桩距离隧道越近,基坑开挖对既有地铁隧道变形的影响越小。更多还原

【Abstract】 The unloading effect of surrounding soil will affect the deformation and normal use of existing metro tunnels adjacent to deep excavation. The influence of position of isolated pile on deformation of metro tunnel deserves research. Based on building-foundation excavation engineering adjacent to existing metro tunnel in Hangzhou,which uses the protection of isolated pile,numerical simulation is run by the ABAQUS software.Through establishing a 2D model,deformation of tunnel is analyzed in different positions of isolation piles. The results show that,the final settlement of tunnel caused by excavation is approximately 3. 1 mm, horizontal displacement of tunnel closed to excavation is about 1. 7 mm,numerical simulation is anastomosed with field test;isolation pile to tunnel gets closer,the deformation of existing tunnel decreases gradually.更多还原