钢筋锈蚀作用下隧道衬砌结构力学性能劣化研究  

Research on Deterioration of Mechanical Properties of Tunnel Lining Structure under Reinforcement Corrosion

作　　者：李永珑[1,2] 刘新华 朱星宇[1,2] 唐旭 张志强 LI Yonglong;LIU Xinhua;ZHU Xingyu;TANG Xu;ZHANG Zhiqiang(Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [2]西南交通大学土木工程学院,四川成都610031

出　　处：《铁道学报》2024年第1期156-163,共8页Journal of the China Railway Society

基　　金：国家自然科学基金(U1934213)。

摘　　要：考虑锈蚀引起的钢筋力学性能劣化、混凝土有效截面减少、两者黏结性能退化等因素,建立围岩压力作用下钢筋锈蚀隧道衬砌模型,对不同锈蚀率下衬砌结构变形、损伤、内力重分布和裂缝宽度变化进行分析。研究结果表明,锈蚀对衬砌结构各部位损伤严重程度表现为拱顶>拱肩>拱脚>拱腰>仰拱;锈蚀引起结构内力重分布,当锈蚀率由0%发展到20%时,衬砌结构临空侧受拉处弯矩逐渐减小,围岩侧受拉处的弯矩逐渐增大,衬砌轴力整体变化不大,最大变化量仅为7.53%;拱顶裂缝宽度发展最快,拱肩和拱脚次之,当锈蚀率发展到2.7%时,拱顶最大裂缝宽度已不满足耐久性要求;开裂区钢筋锈蚀对衬砌力学性能劣化起主导作用,仅开裂区钢筋发生锈蚀时,衬砌结构力学性能劣化规律与钢筋全长锈蚀情况类似,但锈蚀导致的内力变化幅度和裂缝宽度减小。Considering the factors caused by corrosion such as deterioration of mechanical properties of reinforcement,reduction of effective section of concrete and degradation of bonding properties,a model of reinforcement corrosion tunnel lining under the action of surrounding rock pressure was established.The changes of deformation,damage,internal force and crack width of the lining structure under different corrosion rates were analyzed.The results show that:The order of severity of the lining structure by corrosion is as follows:arch crown>spandrel>arch abutment>hance>inverted arch.Corrosion causes the redistribution of internal forces in the structure.When the corrosion rate develops from 0%to 20%,the bending moment of the tension part on the inner side of the lining structure gradually decreases,while the bending moment of the tension part on the outer side of the lining structure gradually increases.There is little change in the axial force,with the maximum change in axial force at only 7.53%.The crack width of arch crown develops the fastest,followed by the spandrel and arch abutment.The maximum crack width at the arch crown already does not meet the durability requirements when the corrosion rate develops to 2.7%.The influence of corrosion of the reinforcement in the cracked area plays a dominant role in the deterioration of the mechanical properties of the lining.In the case of corrosion only in the cracked area,the low of the lining structure mechanical properties deterioration is similar to that of full-length corrosion of reinforcement.However,the result shows the decreasing of magnitude of internal force change and crack width due to corrosion.

关 键 词：衬砌结构 混凝土损伤 锈蚀 内力重分布 裂缝宽度 

分 类 号：U451.4[建筑科学—桥梁与隧道工程]