火灾下盾构隧道衬砌拼接接头力学行为试验研究  

Experimental study on mechanical behavior of splicing joints of shield tunnel lining subjected to fire

作　　者：郭震 宋隽[1] 刘毅 王香仁 刘毅波 马闯 李富民 Guo Zhen;Song Jun;Liu;Yi Wang;Xiangren;Liu Yibo;Ma Chuang;Li Fumin(School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou 221116,China;Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Engineering,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学力学与土木工程学院,江苏徐州221116 [2]中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室,江苏徐州221116

出　　处：《土木工程学报》2022年第3期94-104,共11页China Civil Engineering Journal

基　　金：国家自然科学基金(51878656);江苏省重点研发计划(BE2018636)。

摘　　要：盾构隧道管片接头是隧道结构的薄弱部位,针对盾构隧道管片接头的抗火性能研究显得尤为重要,该文以存在安装误差的缩尺衬砌结构接头试件进行火灾试验,以管片的表观特征、温度场分布及变形响应等特征,研究火灾高温作用下盾构隧道衬砌结构接头的力学性能。研究结果表明:无初始缺陷的衬砌管片爆裂面积大且深度浅,具有初始缺陷的衬砌管片剥落深度大,其中有错台初始缺陷的衬砌管片剥落深度最大达到72mm,接头破损率达10.52%;有初始缺陷的衬砌管片在降温后有较大的残余变形;有初始缺陷的衬砌管片在火灾作用下弯矩变化更快,其接头的抗弯、抗剪性能急剧下降,表现为接头张角、张开量的值变大,且接头部分发生进一步的错台现象;有初始缺陷的管片接头刚度会比无初始缺陷衰减更快且刚度损失更多,试验结束后其剩余刚度比无缺陷减少69.7%。研究结论可为盾构隧道衬砌拼接接头结构热力耦合研究的进一步发展提供参考。Shield tunnel segment joints are the weak parts of the tunnel structure,so it is particularly important to study its performances,especially fire-resistance performance.The fire-resistance tests were conducted on the lining structure joints with installation errors.The mechanical properties and damage laws of the joints of the shield tunnel lining structure under the fire were studied.The apparent characteristics,temperature field distribution,structural properties and mechanical properties of the post-disaster segment were analyzed.The results show that the lining segment without initial defects has a large burst area and shallow depth,while the lining segment with initial defects has a large peeling depth.The maximum peeling depth of lining segments with initial defects is 72 mm,and the joint damage rate is 10.52%.The lining segment with initial defects has larger residual deformation after cooling.The bending moment of the lining segment with initial defects changes faster under the action of fire.The bending and shear resistance are mainly manifested by the increase in the joint opening angle and the amount of expansion,and the joint part has further misalignment phenomenon.The stiffness of the segment joints with initial defects decays faster and the stiffness loss is greater than those without initial defects.The remaining stiffness after fire decreases about 69.7%.The research results can provide reference for the thermal-mechanical coupling study of shield tunnel lining splicing joint structure.

关 键 词：盾构隧道 管片接头 初始缺陷 火灾试验 火灾损伤 

分 类 号：TU942[建筑科学—建筑技术科学]