基于红外成像技术的叠合剪力墙无损检测方法研究

Research on Non⁃Destructive Testing Method of Superimposed Shear Wall Based on Infrared Imaging Technology

针对目前叠合剪力墙结构缺乏成熟的无损检测技术,本文提出了一种基于红外成像技术的叠合剪力墙无损检测方法。该方法利用现浇混凝土水化热为激励热源,在预制板表面缺陷区域形成温度场差异,运用红外热成像技术检测混凝土缺陷位置和程度。以含有空气缺陷的叠合剪力墙为研究对象,通过有限元分析,研究了缺陷尺寸、厚度对混凝土表面温度场的影响,及缺陷处与密实区域混凝土表面温度场的分布规律;通过模型检测试验,研究了现浇混凝土水化热主动激励检测叠合剪力墙缺陷的可行性,且探究了加热时长对最佳检测时段的影响。结果表明,该检测方法可检测出预叠合剪力墙内厚度为5 mm直径不小于30 mm及厚度为10 mm直径不小于20 mm大小的缺陷,并明确最佳检测时段为浇筑完成后10~12 h。

In response to the current lack of mature non⁃destructive testing technology for superimposed shear wall structures,this paper proposes a non⁃destructive testing method for superimposed shear walls based on infrared imaging technology.The principle of this method is to use the hydration heat of newly poured concrete as an exciting heat source to form temperature field differences in the surface defect areas of prefabricated panels,and uses infrared thermal imaging technology to detect the location and degree of concrete defects.Taking composite shear walls with air defects as the research object,the influence of defect size and thickness on the temperature field of concrete surface was studied through finite element analysis,as well as the distribution law of concrete surface temperature field in defect and dense area;based on the model test,the feasibility of detecting the defects of superimposed shear wall based on the hydration heat of newly poured concrete as an active excitation was studied,and the influence of heating time on the optimal detection period was explored.The results indicate that this detection method can detect defects with a thickness of 5 mm and a diameter of no less than 20 mm and a thickness of 10 mm and a diameter of no less than 30 mm in the superimposed shear wall,and it is clear that the optimal detection period is 10-12 hours after the completion of pouring.