摘要
隧洞衬砌内部缺陷精准定量检出一直是工程难点问题,超声横波成像是当前国内外无损检测混凝土缺陷的前沿技术。通过模型试验分析了不同频率下超声横波成像的响应特征,提出隧洞衬砌内部缺陷定量辨识方法。在超声成像图谱中,钢筋、混凝土及缺陷交界面的色彩区分度明显;当超声发射频率超过25 kHz时,检测图谱中能够有效识别首层钢筋;常规混凝土内部缺陷较佳检测效果的超声发射频率为45 kHz~55 kHz;根据超声成像中异常反射区域可确定衬砌脱空缺陷的位置,根据异常反射出现的深度和正常衬砌厚度,可计算衬砌脱空缺陷的厚度,实现对衬砌内部缺陷的定量辨识。通过在工程中进行应用,并经钻孔内窥镜验证,超声横波成像能够有效定量辨识混凝土衬砌脱空缺陷。
Accurate and quantitative detection of internal defects in tunnel linings has always been a difficult engineering problem, and ultrasonic transverse wave imaging is the current cutting-edge technology for non-destructive testing of concrete defects at home and abroad. The response characteristics of ultrasonic transverse wave imaging at different frequencies are analyzed through model tests, and a quantitative identification method for internal defects in tunnel linings is proposed. In the ultrasonic imaging mapping, the color differentiation between the intersection of reinforcement, concrete and defects is obvious;when the ultrasonic emission frequency exceeds 25 kHz, the first layer of reinforcement can be effectively identified in the detection mapping;the ultrasonic emission frequency for better detection of conventional concrete internal defects is 45 kHz~55 kHz;the location of lining debonding defects can be identified according to the abnormal reflection area in the ultrasonic imaging, and according to the abnormal reflection Based on the depth of the abnormal reflection and the normal lining thickness, the thickness of the lining debonding defect can be calculated to achieve quantitative identification of internal lining defects. Through application in engineering and verification by borehole endoscopy, ultrasonic transverse wave imaging can effectively identify concrete lining debris defects quantitatively.
作者
杨建喜
张盛行
汤雷
李军
潘文明
YANG Jianxi;ZHANG Shenghang;TANG Lei;LI Jun;PAN Wenming(Guangdong GDH Pearl River Delta Water Supply Co.,Ltd.,Guangzhou,Guangdong 51000,China;Nanjing Hydraulic Research Institute,Nanjing,Jiangsu 210029,China)
出处
《水利与建筑工程学报》
2022年第6期195-200,共6页
Journal of Water Resources and Architectural Engineering
基金
国家重点研发计划项目课题(2021YFC3090103)
中央级公益性科研院所基本科研业务费专项(Y421006,Y421008,Y418005)。
关键词
混凝土衬砌
内部缺陷
超声横波
模型试验
工程实践
concrete lining
internal defects
ultrasonic shear wave
model test
engineering practice
