摘要
隧道衬砌结构服役现状的稳定性评价是开展维修加固的关键依据。依托HTG隧道工程实例,建立了基于荷载-结构法的大面积腐蚀隧道衬砌结构计算模型,并针对不同衬砌腐蚀深度和腐蚀范围对隧道衬砌结构受力状态和安全系数分布特征开展了多工况计算分析。结果表明,当隧道衬砌发生大面积腐蚀后,衬砌结构的轴力变化较小,结构内力的变化主要体现在衬砌弯矩的变化上,进而导致衬砌单元的偏心距增大;隧道边墙和拱脚位置属于发生腐蚀的危险区域,当该处衬砌发生大面积腐蚀后,隧道衬砌的危险截面数量较多,隧道衬砌的整体结构稳定性面临危险。在此基础上,进一步将隧道衬砌划分为5个子系统组成的串联结构体系,提出了基于截面安全概率的腐蚀隧道衬砌结构安全性评价等级分级计算方法,并将其应用至HTG隧道工程中,获得了该隧道衬砌在不同位置发生硫酸盐腐蚀后的安全概率及安全等级,可为后续隧道衬砌的维修加固提供依据。
The stability evaluation for tunnel lining structure in service is the key basis for maintenance and reinforcement.As for the HTG tunnel project,this paper established a load-structure method based calculation model of tunnel lining with large areas of corrosion,and in terms of corrosion depth and scope,the stress conditions and safety coefficient distribution characteristics of tunnel lining structure were calculated and analyzed under different working conditions.The results show that after occurring large areas of corrosion in the tunnel lining,the change of axial force of lining structure is small,the change of internal force of structure is mainly reflected in the change of bending moment of lining,which leads to the increase of eccentricity of lining element.The tunnel side wall and arch foot belong to the dangerous area of corrosion.When the tunnel lining at those parts has a large area of corrosion,the number of dangerous sections of the tunnel lining is larger,and the overall stability of the tunnel lining structure is in danger.On this basis,the tunnel lining is divided into a series structure system composed of five subsystems,and a calculation method is proposed for evaluating the safety level of the corroded tunnel lining structure based on cross section safety probability.It was applied to the HTG tunnel project,the safety probability and safe level were obtained with respect to the sulfate corrosion conditions in different tunnel lining positions.It can provide a basis for the maintenance and reinforcement of tunnel lining.
作者
段炼
李永恒
伍江航
DUAN Lian;LI Yongheng;WU Jianghang(Zhangjiajie Works Section,China Railway Guangzhou Bureau Group Co.,Ltd.,Zhangjiajie 427000;School of Civil Engineering,Central South University,Changsha 410075)
出处
《现代隧道技术》
CSCD
北大核心
2022年第5期212-220,共9页
Modern Tunnelling Technology
基金
广铁(集团)公司科技创新专项项目(2020K041-G).
关键词
铁路隧道
硫酸盐侵蚀
衬砌腐蚀
结构稳定性
影响规律
评价方法
Railway tunnel
Sulfate erosion
Corrosion of lining
Structural stability
Law of influence
Evaluation method
