Shanghai has built and operated more than 800 kilometers of tunnels, mainly subway tunnels, urban highway tunnels and electric power tunnels. As the city's traffic and energy lifeline, its healthy service is very important for the normal operation of the city. Especially, most of the above tunnels are assembled by segments or pipe joints, and the problems of any segment or pipe joint will lead to the operation of section tunnels being affected or even paralyzed. Therefore, it is necessary to carry out full-area detection and safety warning for potential safety hazards such as tunnel structure surface diseases (uneven settlement, cracking, leakage) and hidden area diseases (such as stiffness weakening and cavity behind). At the same time, due to the randomness and concealment of the occurrence and development of the above diseases, it is difficult to select and make decisions for tunnel detection and safety warning targets. Therefore, it is necessary to develop hidden surface testing technology and introduce information means to enhance information traceability.
Focusing on the technical problems of tunnel structural safety early warning, this project has worked through joint research of industry, academia and research. It has lasted for 10 years and has overcome the automatic acquisition and information management of tunnel daily inspection data, safe and reliable mobile rapid nondestructive testing and diagnosis of tunnels, and distributed monitoring of tunnel operations. Key technologies such as systems and early warning platforms have formed key technologies and equipment to ensure urban tunnel structural safety early warning. The main contents and technical and economic indicators are as follows:
(1) Developed a mobile electronic tunnel inspection system based on a handheld PDA, and established a daily inspection software and background management platform based on a PDA, solving the problems of daily mobile inspection and data information management of tunnels. Sensor data can be dynamically read and collected when the vehicle is traveling at a speed of less than 20km/h, and transmitted to the management terminal. The electronic and mobile inspection work has been realized, greatly improving efficiency.
(2) Developed a tunnel full-section non-destructive testing vehicle, developed a non-contact tunnel detection air-coupled antenna technology, proposed high-precision imaging of radar electromagnetic wave data and intelligent identification of voids, and realized the structure and its wall Through software and hardware integration, mobile detection of voids in the back grouting layer solves the problem of tunnel hidden surface detection. Its technical indicators are superior to similar products at home and abroad, and it realizes safety detection without stopping the tunnel.
(3) Developed a track-tunnel-soil coupled wave numerical wave simulation method, studied the wave evolution laws of shield tunnel structures, and proposed a performance analysis method for subway tunnel segments in service area, which achieved lightweight tunnel structural wave simulation and solved the problem of rapid evaluation of tunnel regional performance.
(4) A method for processing underground engineering deformation data based on point cloud regular gridding three-dimensional laser scanning is proposed. A technical system for measuring station layout, automatic point cloud processing, rapid acquisition and real-life display of tunnel apparent performance has been formed, which solves the problem of rapid information such as tunnel segment cross-section convergence, longitudinal section deformation, and segment misalignment. problem. The measurement efficiency reaches 500m/h, and the error rate of the major and minor axes of elliptical deformation is less than 2‰.
(5) Developed a complete set of fully automatic safety 3D monitoring software and mobile publishing platform for tunnels. It solves the comprehensive management problems of multiple data fusion, safety warning and control of soft soil tunnels. It has functions such as real-time collection, wireless data transmission and remote terminal control, cloud data processing and real-time warning, realizing round-the-clock real-time warning of the health status of the tunnel structure.
The results have been successfully applied in Shanghai Metro Lines 6, 9, 10, 12 and 13, Shanghai Yangtze River Tunnel, Yangtze River West Road Tunnel, and Yingbin No. 3 Road Tunnel, Shanghai Electric Power Expo Tunnel, Xizang Road Tunnel, Yanggao Road Tunnel, Fuzhou Road Crossing Tunnel, Yangshupu Power Plant Crossing Tunnel and other projects, and the equipment developed has been applied to 50 tunnel sections. In the past three years, the economic benefits generated by the promotion of achievements have reached 530 million yuan, of which 360 million yuan are direct economic benefits. Obtained and applied for 19 patents, 8 software copyrights, published 46 domestic and foreign papers, and promulgated 1 local specification. The results have generally reached the international advanced level, and some have reached the international leading level, promoting the safety warning technology for soft soil tunnel operations in my country. progress.