隧道二衬欠厚检测及结构安全性分析

针对西部某高速铁路隧道二衬病害问题,采用SIR-3000型探地雷达进行二衬检测,根据病害部位、类型以及程度不同,建立多种工况的有限元模型,并以拱顶、拱腰和边墙的安全系数为评价标准,对二衬病害引起衬砌结构安全问题进行总结.检测结果表明:二衬缺陷主要表现为欠厚问题,占总病害数的69.9％,且各部位欠厚数呈正态分布.分析表明...

Tunnel Lining Under-thickness Detection and Structural Safety Analysis

Aiming at the problem of tunnel secondary lining damage in a western high speed railway,this paper revealed the general rule of structural safety change caused by secondary lining defects,and provided theoretical basis for solving similar tunnel problems.Based on a tunnel section in the high speed railway,the SIR-3000 type ground penetration radar was adopted to detect the secondary lining.Finite element models under various working conditions were established on the basis of the position,type and degree of the damage,and the safety factors of vault.Arch waist and side wall were taken as the evaluation criteria to summarize the change rule of the lining structure safety caused by the secondary lining damage.The test results show that under thickness is the main problem of secondary lining defects,accounting for 69.9%of the total number of defects with normally distributed under thickness in each part.The finite element model demonstrates that the under thickness of the second lining makes the internal force smaller as a whole.The closer to the under thickness part,the greater the impact.When the whole secondary lining is under thickness,the critical thickness meets the safety requirement and reaches 19.2 cm.The vault is under thickness,the tensile damage interval of the vault thickness is H;∈16.7,26.3]cm;the arch is under thickness with no limit damage and the side wall is under thickness with 3 cm the critical thickness.