隧道衬砌自动化检测及健康评价技术研究

Research on Automatic Detection and Health Assessment of Tunnel Lining

为进一步提高隧道衬砌的自动化检测及健全度评价技术,基于无损检测技术开展了非可视化高速摄影检测技术和常时微动检测技术研究。非可视化高速摄影检测技术能够实现衬砌表面病害高速检测、自动识别与提取,检测系统行车速度可达到100 km/h,裂缝检测精度可达到0.2 mm(检测车速度100 km/h);常时微动检测技术能够实现提取隧道衬砌内部异常点(包括裂缝和空洞)的自动检测,具有小型化、抗干扰能力强、精度高、无需额外震源等优势。健全度评价方面,提出分形维数、常时微动平均合成谱RAS(resultant average spectrum),结合TCI(tunnel-lining crack index)实现隧道衬砌病害特征的定量化描述,3个指标可以综合考虑裂缝的宽度、长度、方向、数量、交叉分布以及衬砌内部异常等特性,相互结合可以更为准确地确定损伤衬砌段。

Aiming at advancing the automatic detection and health assessment technology for the tunnel lining,nonvisual high-speed photogrammetry and microtremor measurement technology are introduced on the basis of the nondestructive detection technology of tunnel-lining diseases.The nonvisual high-speed photogrammetry technology can automatically identify and extract the lining surface defect with a high-crack width resolution of 0.2 mm under a detection driving velocity of 100 km/h,whereas,the microtremor measurement technology can automatically detect the inner abnormal points(including cracks and cavities)of a tunnel lining.The measurement equipments are characterized by miniaturization,strong anti-interference,high resolution,and nonextra exciting power requirements.Moreover,the fractal dimension and averaged synthetic spectrum resultant average spectrum of a microtremor are proposed,and combining with the tunnel-lining crack index,the quantitative assessment of a health condition can be provided.These three indices can comprehensively represent the characteristics of width,length,crack direction,number,and the distribution of cracks and inner abnormal points of a tunnel lining,determining the damaged lining section with high accuracy.