热力管道大推力固定支架力学作用机制及设计计算方法

Mechanical Mechanisms and Design Calculation Methods for Fixing Supports of Thermal Pipes under Huge Pushing Forces

采用传统理论计算(利用摩阻力)和基于工程实践的优化后理论(利用被动土压力和摩阻力共同作用)计算进行对比的方法,得出了简单配重不是解决明挖大推力检查室内固定支架抗滑移最合理、经济的办法,可充分利用周边土体的被动土压力。通过采取简化的结构受力分析、数值模拟分析、原位试验数据分析,并结合已投入使用的工程实例,得出了在一定范围内暗挖隧道初期支护和二次衬砌共同承担大推力作用,受初期支护和二次衬砌之间防水隔离层影响不大的结论,通过采取必要的构造措施,隧道口设置大推力固定支架是安全可行的。

Comparison and contrast are made between the results of the conventional calculation method and those of the optimized calculation methods, which shows that the simple weight balancing method is neither the most rational nor the most economic means to cope with the sliding of the fixing supports in open-cut inspection chambers under huge pushing forces, andon the contrary, the passive soil pressure of the surrounding soil mass can be fully used. Simplified structur- al load-bearing analysis, numerical analysis, in-situ test data analysis and case histories demonstrate 1Lhat, to some ex- tent, the primary reinforcement and the secondary lining of mined tunnels can undertake the pushing torce together and that fixing supports under huge pushing forces can be installed at the tunnel entrance when necessary countermeasures have been taken.