A Real-time Monitoring System In Displacement Of Metro Tunnel

Metro plays an important part in modern urban transport system. Because of the characteristics of high speed and convenience, more and more people choose it as their vehicle. Particularly in the last 10 years, metro becomes more and more prevalent in our lives. Because of the uneven distribution of horizontal layers, the construction load near the tunnel, the long-term cyclic vibration of the train, the displacement of tunnel will occur. When the displacement overruns the security line, it will pose a threat to the structural safety of the tunnel and the waterproof of the connectors, and then it will influence the formation of the track, and affect the normal operation. Therefore, we must attach importance to the situation of the displacement of the tunnel in the long-term operation, and we should control the displacement from the integrated side, such as design, construction, project control, the impact of the surrounding environment, and so on.The issue comes mainly from horizontal issues; it monitors the displacement of the metro tunnel within real-time, using the Shanghai metro system as background. We designed a multi-point displacement monitoring network system, which is based on image processing, including the monitoring systems in displacement of tunnel in every subway station and the information management system in displacement of tunnel. The monitoring system in every station achieves the image of the target through image sensor, then generates displacement data from the IPC, and transmits these data to the master computer in subway station through RS232/RS485 converter. The master computer implements graphic display and the system alarm. The information management system implements centralized information management to the displacement of Shanghai metro tunnel. The master computer in subway station sends the data to the servers of the control centre through LAN, then the severs storage and backup these data. At the same time, the control centre can activate the monitoring systems in displacement of tunnel in every subway station for data collection and regular demand.