基坑工程时变主动土压力研究

Time-dependent active earth pressure in deep excavation

基坑支护工程中土压力随开挖深度、变形及时间的延续而发生相应变化,设计施工过程中常由于对其时变效应的估计不足而导致支护结构破坏。依据基坑支护工程的实际监测结果反演分析了基坑工程中主动土压力的时变特性,引入假定,推导了土压力随时间变化的计算公式。通过与同类型工程试验结果进行对比分析,验证了本文计算公式所反映基坑主动土压力的时变特性能够满足工程设计要求,对同类基坑支护结构具有一定的参考价值。

The active earth pressure acting on retaining structure in deep excavation is variable and dependent on the excavation depth,the deformation of retaining structure and the time.The retaining structure usually fails for lacking of accurate estimation of the time-dependent property of active earth pressure.The time-dependent property of active earth pressure was back-analyzed based on the lateral deformation of a true excavation engineering,and a formula was put forward in response to an assumption.It revealed that the formula reflected the time-dependent property of active earth pressure in deep excavation engineering,and the calculated results conformed to the requirements of engineering design compared with a true engineering experiment.