地铁盾构隧道下穿既有铁路加固方案数值分析

Numerical Analysis of Reinforcement Scheme for Metro Shield Tunnel Crossing Underneath Existing Railway

地铁盾构下穿铁路施工是一项高风险作业,加固方案的合理性直接影响到隧道施工安全。对于苏州地铁3号线下穿既有铁路加固方案,通过采用三维有限元方法,对盾构隧道的掘进进行数值模拟分析,结果表明:采用加固措施后,地铁盾构在掘进过程中,其地表、桥墩及路基部位的沉降均为超过设计中规定限值;隧道周边采用加固措施后,能够降低左右线隧道掘进相互之间的影响。由此得到,采用加固方案后,地铁盾构在掘进过程中,不影响其上铁路列车行车安全。

The construction of subway shield under passing the railway is a high risk job, the rationality of reinforcement scheme directly affects the safety of tunnel construction. The numerical calculation of shield tunneling was carried out by using the three-dimensional finite element method for the reinforcement of passing through existing subway line in Suzhou Metro Line 3. The results showed that with reinforcement measures in the subway shield tunneling process, the settlement of its surface, piers and parts of the roadbed were exceeding the specified design limits. The reinforcement measures for surrounding tunnel could reduce the impact of left and right line tunneling between each other. Therefore, with the rein- forcement scheme, the subway shield tunneling did not affect the safety of the railway train.