盾构下穿高层结构相互影响及方案优化研究

针对成都地铁盾构隧道下穿高层建筑的实际工程案例,通过三维数值模拟结果及现场实测数据对比分析表明,高层建筑物及盾构隧道应力与变形均在规范允许范围内。模拟盾构隧道与高层建筑6种不同竖向净距下穿的工况,结果表明:随着隧道与筏板基础距离减小,高层建筑沉降及倾斜呈现先增大后减小的趋势,且均远小于规范允许值。同时提取数值模拟得到的管片内力及变形数据,与荷载-结构法计算的管片内力及变形数据进行对比分析,表明随着隧道与筏板基础距离减小,盾构隧道弯矩、计算裂缝宽度及隧道变形呈先增大后略微减小的趋势,且均满足规范要求,管片结构安全。

Study on interaction and scheme optimization of shield under passing high-rise structure

According to the actual engineering case of Chengdu metro shield tunnel passing through the high-rise building,the comparative analysis of threedimensional numerical simulation results and field measured data shows that the stress and deformation of the high-rise building and shield tunnel are within the allowable range of the requirements.The results show that with the decrease of the distance between the tunnel and the raft foundation,the settlement and inclination of the high-rise buildings increase fi rst and then decrease,which are far lower than the allowable value of the specifications.At the same time,the internal force and deformation data of segments obtained from numerical simulation are extracted and compared with the internal force and deformation data of segments calculated by load structure method.It is shown that with the decrease of the distance between the tunnel and raft foundation,the bending moment,calculated crack width and tunnel deformation of shield tunnel first increase and then slightly decrease,and all meet the requirements,so the segment structure is safe.