隧道衬砌纵向裂缝对结构力学形变与安全特性的影响研究  

Impact of longitudinal cracks on the structural deformation and safety characteristics of tunnel lining

作　　者：杨治军 王永刚 刘泾堂 胡金鑫 Yang Zhijun;Wang Yonggang;Liu Jingtang;Hu Jinxin(Gansu Province Transportation Planning,Survey&Design Institute Co.,Ltd.,Lanzhou 730030,Gansu,China)

机构地区：[1]甘肃省交通规划勘察设计院股份有限公司,甘肃兰州730030

出　　处：《岩土工程技术》2025年第2期177-184,共8页Geotechnical Engineering Technique

摘　　要：为了研究运营隧道纵向裂缝发育性状对二次衬砌结构受力及形变特征的影响规律,根据隧道裂缝调查结果建立衬砌结构的荷载–结构计算模型,并进行带裂缝衬砌结构的受力变形分析。结果表明:衬砌开裂导致支护结构(除仰拱外)的受力(弯矩绝对值)减小,裂缝深度增加使得结构弯矩出现两次突变,造成局部应力瞬间损失,但衬砌厚度的增加一定程度减缓了应力损失;拱顶与拱肩附近裂缝处结构变形较为严重,结构安全系亦显著降低,当裂缝深度占比衬砌厚度约70%时(拱顶开裂时占比约40%),衬砌结构安全系数降低至零,且随着裂缝数量增加,衬砌结构整体安全性呈线性降低。可见,衬砌裂缝发育到一定程度时,结构整体安全系数小于设计规范所规定的下限值,对起拱线以上裂缝应及时探明裂缝深度并控制其变形,起拱线以下裂缝处易发生压碎破坏,应及时补强支护,以抵抗拱脚上部衬砌结构的下压力,对运营隧道衬砌病害处治具有理论指导意义。To investigate the influence of longitudinal crack development on the mechanics and deformation characteristics of the secondary lining structure,a load-structure calculation model was established based on tunnel crack investigation.Stress deforma-tion analysis was conducted for the cracked lining structure.The results indicate that cracking in the lining leads to a decrease in stress(absolute bending moment)in the supporting structure(excluding invert).Moreover,an increase in crack depth causes two changes in bending moment within the structure,resulting in instantaneous local stress loss.However,an increase in lining thickness mitigates this stress loss to some extent.Severe structural deformations occur near cracks at both arch and spinner locations,significantly comprom-ising structural safety.When crack depth accounts for approximately 70%of the lining thickness(around 40%for arch cracks),the safety factor of the lining structure decreases to zero and overall safety linearly declines with an increasing number of cracks.It is evid-ent that when cracking reaches a certain extent,overall safety falls below design specification limits,therefore timely verification and control measures should be implemented for cracks above the arch line to effectively manage their associated deformations.Cracks be-low this line are prone to crushing damage;hence reinforcement support should be promptly applied to withstand downward pressure from above-the-arch footlining structures.It has theoretical guidance significance for the treatment of lining diseases in operating tun-nels.

关 键 词：裂缝性状 荷载–结构模型 力学形变 安全系数 

分 类 号：U451[建筑科学—桥梁与隧道工程]