弹性软化的深埋泥岩隧道围岩变形特征  

Deformation Characteristics of Deep Buried Tunnel in Softening Elasticity Mudstone

作　　者：马传明 MA Chuanming(China Railway 20th Bureau Group Second Engineering Co.Ltd.,Xi’an 710021,China)

机构地区：[1]中铁二十局集团第二工程有限公司,西安710021

出　　处：《铁道建筑》2025年第1期116-120,共5页Railway Engineering

基　　金：中铁二十局集团有限公司科研计划(YF2302SD07B)。

摘　　要：隧道围岩含水量的变化对地层力学性质影响显著,易导致隧道变形及衬砌损伤。以一座深埋泥岩地层隧道工程为背景,采用现场监测、室内试验和数值模拟相结合的方法,研究了泥岩地层隧道围岩变形特征及发生机制。建立了与正线隧道断面相同尺寸的试验洞,使用多点位移计监测试验洞围岩位移变化情况;对泥岩进行膨胀压力试验,并反演膨胀系数;构建了考虑地层遇水膨胀、软化效应的隧道变形数值分析模型,并结合现场监测数据验证模型的可靠性,分析了不同湿度应力场条件下泥岩地层隧道的变形情况。结果表明:受湿度应力场的影响,泥岩隧道在开挖后,围岩出现了膨胀变形和强度劣化,围岩变形向远离隧道衬砌的方向发展,且呈持续增长的趋势。泥岩遇水软化是围岩变形持续增长的主要原因。The variation in groundwater content of tunnel surrounding rocks significantly impacts the mechanical properties of the strata,leading to tunnel deformation and lining damage.Using a deep buried mudstone tunnel project as a case study,this paper combined field monitoring,laboratory testing and numerical simulation to investigate the deformation characteristics and mechanisms of tunnel surrounding rocks in mudstone strata.A test tunnel with dimensions identical to the actual tunnel cross-section was established,and the displacement development of the surrounding rock was monitored using multi-point displacement meters.Expansion pressure tests were conducted on the mudstone to reverse the expansion coefficient.A numerical simulation model of tunnel deformation was developed,accounting for the effects of water-induced expansion and softening of the strata,and the reliability of model was verified with field monitoring data.The deformation of the mudstone tunnel under different humidity conditions was analyzed.The results show that,after excavation,the mudstone tunnel is affected by humidity conditions,resulting in expansion deformation and strength degradation.The displacement of the surrounding rock progresses away from the tunnel lining and shows a continuous growth trend.The water-induced softening effect of the mudstone is the primary cause of the ongoing displacement increase.

关 键 词：铁路隧道 围岩变形 数值模拟 深埋隧道 泥岩 遇水膨胀 软化效应 试验洞 

分 类 号：U451.2[建筑科学—桥梁与隧道工程]