铁路隧道结构设计参数对二次衬砌裂缝影响规律研究  

Study on the Influence Law of Structural Design Parameters of the Railway Tunnel on Secondary Lining Cracks

作　　者：朱星宇 刘征 张志强[1] 冯应 ZHU Xingyu;LIU Zheng;ZHANG Zhiqiang;FENG Ying(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031)

机构地区：[1]西南交通大学土木工程学院,成都610031

出　　处：《现代隧道技术》2023年第5期1-10,共10页Modern Tunnelling Technology

基　　金：国家自然科学基金高铁联合基金(U1934213)。

摘　　要：对玉磨铁路安定隧道二次衬砌裂缝的分布进行统计分析,并提出一种更接近实际荷载情况的模拟方法,对二次衬砌的裂缝发展规律和控制因素进行研究。采用正交试验研究四因素(混凝土强度等级、衬砌厚度、钢筋直径、保护层厚度)三水平条件下衬砌裂缝情况。结果表明:现场衬砌裂缝分布情况统计显示裂缝主要分布于拱脚和拱腰位置,拱顶次之,拱肩裂缝较少,纵向裂缝比例达到63%,环向裂缝和斜向裂缝占比分别为18%和19%;衬砌各部位损伤出现的顺序为拱脚、拱顶、拱腰、拱肩,而裂缝发展程度一般为拱脚>拱腰>拱顶>拱肩;二次衬砌结构参数对拱脚裂缝宽度的影响程度为混凝土强度等级>保护层厚度>衬砌厚度>钢筋直径;随着因素水平的提升,混凝土强度等级、衬砌厚度、钢筋直径的影响程度逐渐减小,衬砌厚度影响趋势则相反。Statistical analysis is conducted on the distribution of cracks in the secondary lining of the Anding Tunnel of the Yuxi-Mohan Railway,and a simulation method closer to the actual load is proposed to study the development law and control factors of cracks in the secondary lining.Orthogonal test is conducted to study the lining cracks under three levels of four factors(concrete strength grade,lining thickness,steel bar diameter,and protective layer thickness).The results indicate that the distribution of cracks in the lining on site shows that the cracks are mainly distributed at the arch foot and arch hance,secondarily at the crown,with fewer cracks at the spandrel,and the longitudinal cracks account for 63%and 18%and 19%for circumferential and slanting cracks,respectively.The occurrence order of damage to various parts of the lining is arch foot,crown,arch hance,and spandrel,while their degrees of crack development are sorted as follows:arch foot>arch hance>crown>spandrel.The influence degrees of secondary lining structural parameters on the width of arch foot crack are sorted as follows:concrete strength grade>protective layer thickness>lining thickness>steel bar diameter.As the factor level increases,the influence of concrete strength grade,lining thickness,and steel bar diameter gradually decreases,while the influence trend of lining thickness is opposite.

关 键 词：铁路隧道 裂缝分布 正交试验 荷载结构法 地层结构法 应力张量 

分 类 号：U451.4[建筑科学—桥梁与隧道工程]