隧道衬砌浅层剥离的红外探测方法  

Infrared detection method for shallow peeling of tunnel lining

作　　者：刘学增[1] 唐精[1] 杨芝璐 谷文川 段俊铭 LIU Xuezeng;TANG Jing;YANG Zhilu;GU Wenchuan;DUAN Junming(College of Civil Engineering,Tongji University,Shanghai 200092,China;Shanghai Engineering Research Center of Underground Infrastructure Detection and Maintenance Equipment,Shanghai 200092,China;Tongyan Civil Engineering Technology Co.,Ltd.,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院,上海200092 [2]上海地下基础设施安全检测与养护装备工程技术研究中心,上海200092 [3]上海同岩土木工程科技股份有限公司,上海200092

出　　处：《岩石力学与工程学报》2021年第S01期2876-2887,共12页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金面上资助项目(51878497);贵州省科学技术厅重大科技专项(黔科合重大专项字[2018]3011);浙江省交通运输厅科技项目(2018011)。

摘　　要：由于衬砌材料劣化或钢筋锈蚀等因素容易导致浅层混凝土剥落,对隧道行车安全将造成严重影响,通过无损检测技术及时发现混凝土剥离现象,判断剥落的可能性十分必要。本文通过数值分析、室内和现场试验的方法,在自然温差和热激励条件下,分析衬砌混凝土内部剥离深度、剥离范围和隧道衬砌内外温差对衬砌混凝土热传导效应的影响规律,探究衬砌混凝土浅层剥离问题红外探测的可行性。研究结果表明,混凝土剥离深度10 mm,隧道内外温差8.06℃时,可探测边长为80 mm正方形大小的剥离范围;剥离深度50 mm,隧道内外温差为11.9℃时,可探测边长不小于150 mm正方形大小的剥离范围;自然条件下,隧道衬砌50 mm内的浅层剥离采用红外热像仪探测具有可行性,且剥离深度越浅,探测可行性越高;随隧道衬砌内外温差、剥离范围的增大,剥离位置与完好位置的衬砌表面温差线性增加。热激励条件下,红外探测的效果显著提升,但对于边长小于20 mm的缺陷仍不可探测。Because of the deterioration of lining materials or corrosion of steel bars,it is easy to cause shallow concrete spalling,which will seriously affect the safety of tunnel operation.It is necessary to find the concrete spalling phenomenon in time through non-destructive testing technology and judge the possibility of spalling.The purpose of this paper is to explore the feasibility of using infrared thermal imaging technology to detect the peeling defects of lining concrete.The methods of numerical analysis,indoor tests and field tests are used to analyze the influence factors on the temperature field of lining inner surface under natural environment and heating conditions.These factors include stripping depth,size and temperature difference between the two sides of the lining.The results show that,the square shallow peeling defects with side length of 80 mm can be detected when the spalling depth is 10 mm and the temperature difference between the two sides of the lining is 8.06℃.And when the spalling depth is 50 mm and the temperature difference reaches 11.9℃,it is possible to detect the peeling range with side length no less than 150 mm.It is feasible to detect the shallow spalling defects of tunnel lining within 50 mm depth by infrared thermal imager under natural conditions,and the detection feasibility increases with the decrease of defect depth.Moreover,the temperature difference between the stripping position and the intact position on the detection surface is proportional to the temperature difference between the two sides of the lining,and increases linearly with the increase of the side length of the peeling range.Under the heating condition,the effect of infrared detection is obviously improved,but it is still not available for defects with side length less than 20 mm.

关 键 词：隧道工程 衬砌剥离 红外检测 数值分析 室内试验 现场试验 

分 类 号：U45[建筑科学—桥梁与隧道工程]