盾构隧道开挖面稳定的可靠度研究

目前,盾构隧道开挖面稳定性评价方法均是确定性方法.为了考虑土体参数的变异性,提出用可靠方法来评价其稳定程度.采用数值模拟方法,研究了隧道开挖面极限支护压力.基于BP神经网络预测大量给定地层参数工况下的开挖面极限支护压力,对其进行统计,得其概率分布特征.在理论分析的基础上,结合工程实际,探讨了盾构施工土压力的确定原理.建立了隧道开挖面稳定的极限状态方程,对其进行了可靠度分析.该研究除能够科学、合理地评价开挖面的稳定程度外,对于盾构施工过程中合理地设定开挖面支护压力也具有一定的参考作用.

Research on reliability of excavation face stability in shield tunneling

Research methods for excavation face stability in shield tunneling are deterministic methods at present.In order to account the variability of soil parameters,reliability method to assess tunnel excavation face stability is proposed.Limit support pressure at excavation face of shield tunneling is studied with numerical simulation.Limit support pressures with different soil parameter samples are forecasted by BP neural network.Then the probability distribution of them is gained.Principle of determining the e...