The Wall Displacement Monitoring System Within Real-time Of Shanghai Metro Line 8

Along with the development of Country's urbanization process, More and more people flock to the cities, but also bring with it a range of issues in urban transportation. As a modern urban transport system composed of an important part, metro not only solve the difficult problem of the trip, but also has become an indispensable part of city life because of its high-speed, convenient features and widely accepted. 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 over run the security line, it will pose a threat to the structural safety of the tunnel and the waterproof of the connectors, then it will influence the formation of the track, and drive the train accident. As a result, it's important to take an effective approach for long-term operation of the tunnel wall displacement in real-time monitoring.For the existing problems of subway tunnel, by studying a variety of monitoring methods, we develop a new monitoring method-long distance pipeline displacement of real-time monitoring, to effectively improve the existing monitoring methods in the course of problems, and to provide a well-functioning and relatively comprehensive monitoring system for the construction of the tunnel wall. The monitoring methods combine the current growing electronic information with surveying, through the image sensor data collection, computer data processing, real-time displacement of the display pipeline.This paper chose Shanghai Metro Line 8 as the research object, and describe this real-time monitoring of the tunnel wall displacement system, introduce detailed description of the subway tunnel on-site conditions and the overall design ideas and installation process. This system refers the former methods which detect the displacement by force or laser and then offers a new way to monitor the displacement by digital image processing. Through repeated tests in Metro to verify its performance, it fully proves that the system has advantages of high accuracy, real-time good and easy to operate.