摘要
为探明初期支护中钢拱架锈蚀对隧道支护体系承载力的影响,考虑锈蚀条件下工字钢与混凝土之间粘结滑移退化本构关系,将其引入ANSYS模型中,分析钢拱架锈蚀状态下隧道支护体系受力变化规律。结果表明:(1)钢拱架自身承载能力随着锈蚀率的增加而降低,降低幅度与初期支护初始承载比例有关,在锈蚀率ρ=70%时,钢拱架基本不承受弯矩,在ρ=80%时,钢拱架轴力基本为0,其承载能力全部丧失;(2)在未发生锈蚀时,初期支护初始承载比例越大,初期支护与二次衬砌间接触压力越小,随着锈蚀率逐渐增大,接触压力增加值和增大比例也越来越大;(3)初期支护混凝土和二次衬砌的安全系数随锈蚀率增加而逐渐降低。
In order to find out the influence of steel rib corrosion in the initial support on bearing capacity of tunnel support system,the constitutive relation of bond-slip degradation betweenⅠ-beam and concrete under the condition of corrosion was considered and then introduced into the ANSYS model to analyze the stress change law in the tunnel support system under the condition of steel rib corrosion.The results show that:(1)the bearing capacity of steel rib frame decreases along with the increase of corrosion rate,of which the decrease range is related to the initial bearing ratio of the initial support,the steel rib basically does not bear bending moment at p=70%the axial force of steel rib is basically 0 at the corrosion rateρ=80%and the bearing capacity of steel rib is lost atρ=80%;(2)in case of no corrosion,the greater the initial bearing ratio of the initial support is,the smaller the contact pressure is between the initial support and the secondary lining.Along with the gradual increase of the corrosion rate,the increase value and proportion of the contact pressure turns greater gradually;(3)the safety factor of initial support concrete and secondary lining decreases gradually along with the increase of corrosion rate.
作者
张艺腾
王明年
杨恒洪
刘轲瑞
李海军
ZHANG Yiteng;WANG Mingnian;YANG Henghong;LIU Kerui;LI Haijun(Key Laboratory of Transportation Tunnel Engineering,Ministry of Edueation,Southwest Jiaotong University,Chengdu 610031;Sehool of Civil Engineering,Southwest Jiaotong University,Chengdu 610031)
出处
《现代隧道技术》
CSCD
北大核心
2021年第S01期56-63,共8页
Modern Tunnelling Technology
基金
国家自然科学基金(51878567)
中国国家铁路集团有限公司科技研究开发计划课题(P2019 G038-5)
作者简介
张艺腾(1992-),男,博士研究生,主要从事地下工程结构耐久性方面的研究,E-mail:zytzytlvzq@163.com;通讯作者:王明年(1965-),男,博士,教授,博士生导师,主要从事隧道与地下工程的设计研究工作,E-mail:wangmingnian@swjtu.edu.cn.
