考虑抗拉强度截断效应的双模式盾构穿越土岩复合地层开挖面稳定性研究  

Excavation Face Stability Analysis of a Double-Mode Shield Crossing Soil and Rock Composite Strata Based on Tensile Strength Cut-off Effect

作　　者：黄阜 肖辉 王勇涛 张敏 陈晶晶 方薇 HUANG Fu;XIAO Hui;WANG Yongtao;ZHANG Min;CHEN Jingjing;FANG Wei(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China;School of Traffic&Transportation,Changsha University of Science&Technology,Changsha 410114,Hunan,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114 [2]长沙理工大学交通运输学院,湖南长沙410114

出　　处：《隧道建设(中英文)》2025年第1期109-119,共11页Tunnel Construction

基　　金：国家自然科学基金面上项目(52278395,52178413);长沙理工大学研究生实践创新项目(SLSJCX22054)。

摘　　要：为解决已有的基于极限分析的双模式盾构开挖面稳定性研究均未考虑抗拉强度截断效应难以反映开挖面前方岩土体的真实破坏特征问题,利用空间离散技术构建考虑抗拉强度截断效应的双模式盾构在土岩交替复合地层中掘进施工的开挖面三维破坏机制。通过计算破坏机制中的内外能耗功率方程,得到双模式盾构在穿越土岩交界面过程中开挖面支护力的目标函数,采用优化计算获得盾构穿越土岩交界面过程中维持开挖面稳定的支护力最优上限解;采用数值模拟技术计算双模式盾构穿越土岩交界面过程中维持开挖面稳定的极限支护力。结果表明:1)考虑抗拉强度截断效应的开挖面支护力大于未考虑该效应的支护力,开挖面支护力随着抗拉强度折减系数ξ增大而减小;2)将数值模拟获得的支护力与本文理论方法计算得到的支护力进行对比,验证了本文提出的理论方法是有效的。Existing studies on the stability analysis of excavation faces for double-mode shields do not consider the tensile strength cut-off effect,making it challenging to accurately reflect the actual failure characteristics of soils ahead of the excavation face;to address this,a three-dimensional failure mechanism for the excavation face of a double-mode shield crossing soil and rock composite strata is constructed using a spatial discretization technique that incorporates the tensile strength cut-off effect.The internal and external energy consumption power equations for this mechanism are derived,and the objective function of the support pressure for the double-mode shield excavation face is established.The optimal support pressure for the excavation face of a double-mode shield at the soil and rock interface is determined through optimal computation.A numerical simulation technique also calculates the ultimate support pressure required to maintain excavation face stability.The results indicate the following:(1)The support pressure considering the tensile strength cut-off effect is greater than that without this consideration,and the support pressure decreases as the tensile strength reduction factor increases.(2)A comparison between the support pressure obtained from the numerical simulation technique and that derived from the theoretical method validates the effectiveness of the proposed theoretical method.

关 键 词：土岩交界面 三维破坏机制 开挖面支护力 抗拉强度截断效应 双模式盾构 

分 类 号：U45[建筑科学—桥梁与隧道工程]