Design And Research Of Shield Tunnel Settlement Monitoring System

In recent years,China’s urban rail transit has developed rapidly,effectively alleviating urban traffic congestion.As an important part of urban traffic lifeline,the safe operation of its underground structure is very important.In the process of urban rail transit construction and development,people have not paid enough attention to the safety of urban traffic orbital service.In addition,the longitudinal distance of urban traffic track in China is long,the structure of the underground soil layer is complex and varied,the nature of the soil layer is different,the environment around the track is complex,the frequency of traffic is high,and the vibration amplitude of the train is large,which causes the overall performance of the track to continue to decline.The problem of land subsidence in the vertical direction of the traffic track is particularly prominent,and it has become one of the important issues affecting the safe operation of urban rail transit.It is very important to monitor the vertical settlement degree of urban orbital shield tunnels in real time and accurately.However,there are still many shortcomings in the existing vertical settlement monitoring methods for shield tunnels,whether domestic or foreign.Based on this background,this paper proposes a new method to monitor the longitudinal settlement of shield tunnel by using the inclination sensor and completes the research and design of the measurement system.The system can measure the tunnel.The longitudinal settlement curve has high measurement accuracy and low economic cost,enabling remote monitoring.The main research contents of this subject are as follows: A new method for monitoring the settlement of shield tunnel is proposed.The MEMS inclination sensor is used to monitor the vertical settlement value of the shield tunnel and the theoretical model of settlement is established.Finally,draw the longitudinal settlement curve of the shield tunnel.According to the functional requirements of MEMS tilt sensor to monitor the longitudinal settlement of shield tunnel,the whole circuit is designed.The tilt sensorselects the SCA100T series MEMS dual-axis sensor with high measurement accuracy.The safety warning system is proposed and designed.It has a total of health,tertiary,secondary and First-level four warning levels and corresponding pre-planning measures;in order to improve the system measurement accuracy,the system is subjected to temperature compensation analysis,and the least-squares fitting algorithm is used to fit the third-order curve formula of the ambient temperature and the measured angular offset.The offset of the sampled data caused by temperature is intelligently compensated in real time by the program;the median average filtering algorithm is used to implement digital filtering on the collected data;the tunnel settlement curve of the PC end and the mobile phone end is designed and displayed;The maximum measurement error of the test and analysis system is 0.0498°,and the measurement accuracy can reach 0.05°,which meets the system design requirements.