Displacement Data Prediction And Accuracy Analysis Of Simply Supported Girder Bridge Based On ARMA Model

In recent years,bridge safety accidents happen frequently,which have a serious impact on people’s lives,national economy and social stability.Therefore,it is necessary to carry out health monitoring on bridge structures.Deformation is taken as an important basis for bridge structure health monitoring.Deflection directly reflects the stiffness of the bridge;it exists as an extremely important physical quantity in bridge health monitoring system.The deflection of the structure has a direct and close relationship with the stiffness of the bridge.The deflection directly gives the shape change and the size of the deformation at a certain position of the structure.The deflection of the structure has a direct and close relationship with the stiffness of the bridge.The deflection directly gives the shape change and the size of the deformation at a certain position of the structure,and it is an important index to evaluate the quality of the bridge.Therefore,the real-time,systematic and accurate monitoring of the deflection changes at the key positions of the bridge structure is of great significance to the safe operation of the bridge structure and the prevention of bridge collapse and other accidents.This paper predicts the dynamic deflection of a simply supported beam in the span based on the ARMA model.At the same time,the SMTN-X multi-point displacement detection system is used to monitor the mid-span dynamic deflection of the simply supported beam.This method verifies the accuracy of the ARMA model.The main recearch works are as follows:(1)The development status of bridge health monitoring and the application status of ARMA model in bridge health monitoring are defined.How to apply ARMA model in bridge health monitoring and its shortcomings are summarized systematically,which provides a basis for subsequent theoretical research.(2)Two ARMA models were established successively.Through the dynamic test of the maglev car body,the relevant parameters needed by ARMA are obtained.Consider only under the condition of rigid body vibration,first-order ARMA model of car body is established at first,through the body in the body after a simply supported beam into the ARMA model of car body vibration acceleration data,it is concluded that body modal force acting on the bridge,then the dead weight,damping ratio of simply supported beam is obtained by finite element analysis,vibration mode and natural frequency of vibration parameters such as beam was founded after the ARMA model,into the body of car body ARMA model of the bridge after the modal force of the modal response of the bridge,the modal superposition,the midspan deflection of simply supported beam with an analysis of the bridge data.(3)The SMTN-X multi-point displacement detection system is used to monitor the mid-span dynamic deflection of simply supported girder Bridges.By comparing the data obtained from the ARMA model with the actual measured data,the accuracy and reliability of the ARMA model prediction are verified.