Research On Application Of Inclinometer In Deformation Monitoring Of Arch Rib Of Long-span Arch Bridge

With the increasing importance of long-span arch bridges in traffic networks,more and more attention has been paid to the safety of bridges during operation.Arch rib deformation,as the most direct change in the safety of long-span arch bridge,is one of the most important technical parameters for determining the bearing capacity and integrity of long-span arch bridge structure.Therefore,it is necessary to monitor and measure arch rib deformation.Compared with other measurement methods,inclinometer has more advantages in measuring arch rib deformation of long-span arch bridge.This paper takes the development of the arch rib deformation monitoring subsystem of Xinguang bridge as the research background.While the arch rib deformation monitoring subsystem of Xinguang bridge is re-established,the key technology of the application of tilt sensor in the arch rib deformation monitoring of long-span arch bridge is studied.The main research contents of this paper are as follows:(1)According to the principle of the deflection measurement method of the inclinometer,the piecewise superimposed mathematical model is selected to fit the deflection curve of the bridge calculated from the angle.According to the selected mathematical model and the measurement method,the main errors affecting the deflection precision of the inclinometer are analyzed: Segment error and Angle error.Based on these kinds of errors,considering that the measured value of the sensor conforms to the characteristics of normal distribution,monte carlo method is used to evaluate the uncertainty of the inclination sensor measurement.(2)In order to verify the practical effect of the inclination sensor measurement,a simply supported beam was used in the laboratory to test the deflection measurement of the inclinometer,and the rationality of using the inclination sensor to measure the static and dynamic deflection deformation of the bridge beam was analyzed.Based on the test results,the items needing attention to measure the static and dynamic deflection deformation of the bridge beam by using the inclination sensor are analyzed.(3)According to the monitoring content of arch rib deflection deformation of Xinguang bridge,the spatial finite element analysis model of Xinguang bridge was established to obtain the deformation curve of arch rib under different load conditions.The deflection deformation curve under various working conditions is simulated and measured,and the deflection error of measuring control point is calculated and analyzed by taking into account the different sensors with different measuring accuracy,the different number of segments of main arch and side arch,and the different schemes of single and multiple measurements.The measurement results of each scheme are statistically analyzed to select the most suitable sensor layout scheme for each working condition.(4)According to the analysis of the measurement accuracy of arch rib deflection deformation,the installation of the on-site inclinometer and its transmission and communication equipment of Xinguang bridge is carried out.After the inclinometer data is processed,the deflection deformation result of arch rib measured by the inclination sensor is obtained,and the measurement effect is verified by the total station measurement method.Research the main content of this article is using the inclinometer measurement of longspan arch bridge arch rib of the deflection deformation,this method is mainly use high precision inclinometer for arch rib section angle measurement,then the piecewise integral deformation to calculate the vertical deformation of the arch rib,adopt high-frequency synchronous sampling measurement way,the dynamic cycle average measurements to eliminate the dynamic changes of dynamic average deflection,indirect acquire the method of static deflection of the structure.In this paper,the development of the deformation monitoring subsystem of the arch rib of Xinguang bridge is taken as the research background.Before the field measurement,the deflection of the bridge is theoretically calculated,the measurement accuracy and quantity of sensors are designed,the measurement error is analyzed,and the measurement accuracy range is predicted.This method of theoretical analysis before field application is of guiding significance to the final measurement results.In this paper,the application of the inclinometer in the deformation monitoring of the arch rib of Xinguang bridge is studied,which provides a new monitoring method for the same type of projects and has important engineering significance.