The Monitoring Method And Measuring Device For The Secondary Lining In Tunnel Based On The Distributed Strain Measurement

With the rapid development of the highway network,China has become the largest number of tunnels in the world,how to ensure the safety of the tunnel service has become an important part of highway safety operation.The safety and durability of the tunnel can be well reflected by the monitoring of the tunnel.Traditional monitoring methods have some obvious shortcomings such as inconvenience of construction,affected by the environment,equipment price is expensive,not applicable to long-term automation monitoring and other obvious shortcomings.But,the structure deformation is derived from the boundary to the point all the strain accumulation,deformation can be through the new monitoring technology of measuring structure element strain and the boundary conditions for the indirect reasoning structure.The strain distribution monitoring technology is distributed,real-time and long distance,so there are more and more researches on the health monitoring technology of tunnel structure.This article will try to carry out the indirect monitoring from the strain distribution technology,and put forward a kind of monitoring device,achieve a high precision,comprehensive and long-term stability of the monitoring system.The main research contents and innovations of this thesis are as follows:(1)Based on the lateral model of tunnel,taking into account the common section of tunnel lining and load type,this thesis puts forward a simplified model of the deformation of the tunnel.In this thesis,based on the theory of conjugate beam method and the corresponding theory of curved beam,the deformation transfer between the monitoring device and the tunnel is considered,and the corresponding strain deformation algorithm is derived for different section types.(2)In this thesis,the corresponding models are established by different types of tunnel section and different load distribution.Through the analysis of strain and deformation distribution under different conditions,the method for measuring the deformation of tunnel lining convergence based on strain distribution is validated,and the algorithm is modified and the corresponding regression through error analysis.(3)This thesis made a concrete tunnel lining in a laboratory scale model,and measure the deformation-strain distribution through the radial sensing device installed on the model,to verify the feasibility of the monitoring algorithm application in the actual monitoring.Experimental results show that the difference between the calculated displacement and the actual displacement is less than 10%,a small amount of error is slightly larger,but also less than 15%.It shows that the tunnel deformation monitoring method proposed in this thesis has a good monitoring accuracy,while the sensing device monitoring of the tunnel type have high adaptability,good feasibility,it has good application value in practical engineering.