Research On Health Monitoring And Early Warning And Safety Evaluation Of Operational Tunnel Structure

In this thesis,based on the operational tunnel structure health monitoring system,the monitoring system acquisition,transmission,processing,analysis and demonstration are taken as research ideas.For the data acquisition and transmission layer in the monitoring system,a compressed sensing algorithm based on big data sensor network is proposed.The data processing and analysis layer,for the automatic monitoring quantity acceleration response project,establishes the health warning based on the wavelet packet energy spectrum acceleration response tunnel,and adopts the finite element to carry out the safety evaluation of the void behind the lining for the artificial measurement of the lining cavity project;establish a visualized tunnel structure based on BIM warning Health monitoring system.In this thesis,the big data compression sensing for the operational tunnel structure health monitoring system is studied.In order to solve the problem of low transmission bandwidth and high transmission pressure of the sensor network,a sensor network framework is introduced to improve the traditional compressed sensing method.The compression sensing algorithm of sensor network is verified by an example.Based on the wavelet packet energy spectrum acceleration response tunnel health warning,the wavelet packet transform theory is introduced into the acceleration response signal in the automatic monitoring quantity.Based on the wavelet packet spectrum classification and signal denoising threshold criterion,a multi-threshold drop based on wavelet packet spectrum is proposed.Noise method to avoid the interference of high frequency noise on health monitoring;propose a health warning method based on wavelet packet energy spectrum to realize real-time automatic monitoring and high-efficiency warning.Based on the safety evaluation of the void behind the finite element lining,the 10 D,20°,30°,40° range and the double void combination 10° behind the tunnel lining are based on the load structure model for the void problem behind the lining in the artificial detection.Numerical simulations were carried out in the range of 20° and 30°.The safety factor of lining was introduced.The influence of axial force,bending moment and safety factor on the structural safety of single and double voids was analyzed.The safety warning grading under single and double voids was proposed.Based on the BIM technology operation tunnel structure health monitoring system,the construction of the tunnel structure health monitoring system is combined with the tunnel structure safety monitoring and management system to establish the overall structure of the monitoring system;in the data acquisition and transmission layer,the sensor network layout and transmission scheme selection is analyzed;And the analysis layer,study the settlement,dip,acceleration monitoring threshold processing and result evaluation,systematically demonstrate the monitoring quantity and evaluation results;in the visualization of tunnel structure health monitoring,propose the modeling and visualization of shield tunnel based on DYNAMO parameterization Early warning integration.