地铁上盖施工对地铁隧道变形控制及保护措施研究

RESEARCH ON DEFORMATION CONTROL AND PROTECTION MEASURES FOR SUBWAY TUNNEL IN SUBWAY ROOF CONSTRUCTION

以深圳某邻海位于地铁隧道上方建筑物的深基坑项目为背景,分析了在淤泥质土等不良地质条件下对已建成地铁隧道上方基坑设计施工采取格栅加固+抗拔桩+压载板组合方案作为地铁保护措施,达到控制基坑下地铁隧道结构变形在允许范围内的目标。利用midas GTS三维空间有限元计算软件进行全过程施工模拟,分析了不同工况下施工对地铁结构安全的影响。数值模拟表明,现有地铁保护措施可以满足隧道结构的安全控制指标要求。通过实施全自动化监测,验证了地铁隧道变形控制及保护方案的可行性。

Taking the deep foundation pit of a seaside building above the subway tunnel in Shenzhen as the research object,the design and construction of foundation pits above completed subway tunnels under poor geological conditions such as silty soil are analyzed.A combination of grille reinforcement+uplift pile+ballast plate is applied as a subway protection measure to control the structural deformation of subway tunnels under foundation pits within the allowable range.The whole construction process is simulated with midas GTS 3D spatial finite element calculation software,and the impact of construction under subway structures under different working conditions is analyzed.Numerical simulation results show that the existing subway protection measures meet the requirements for safety control indicators of tunnel structures.The feasibility of the subway tunnel deformation control and protection are verified by means of automatic monitoring.