Research On Real-time Monitoring Of Multi Span Concrete Continuous Girder Bridge

Large bridge is an important channel of transportation,which has an important role in social development.With the wide use of large span bridges,people have paid more and more attention to the safety of bridge structure.In order to master the performance of bridge structure and prevent the occurrence of accidents,it is necessary to carry out real-time health monitoring of bridge structure.This paper take Aofeng bridge in Fuzhou as the engineering background,introduces the finite element model updating,performance analysis,and monitoring data analysis,real-time monitoring system layout optimization of force sensor,the main contents are as follows:(1)This paper introduces the research background of bridge real-time monitoring system,the composition and significance of the bridge real-time monitoring system,and summarizes the existing problems of current bridge monitoring.(2)According to the design and completion data of the bridge,establish the initial finite element model using the finite element software ANSYS,and modify computational model according to the dynamic and static load test results,in order to meet the actual state of the structure.Using finite element theory to analyze the mechanical properties of the structure under design load based on the updated finite element mode,and preliminary determine the bridge monitoring index threshold.Constructing "theoretical spectrum" of static and dynamic characteristics of structures,and providing the theoretical basis for the optimal layout of the sensors.Constructing the "standard spectrum" under standard design load on the basis of vehicle load test and ambient vibration test.(3)Expounding briefly the theory method of optimal sensor placement based on the previous research work,determining the types and optimal sensor placement of the real-time monitoring sensor(displacement,acceleration,strain,temperature,etc.)in the prestressed concrete continuous box girder-bridge,and introducing the main framework of the bridge real-time monitoring system.(4)A statistical analysis of the data(displacement,strain and acceleration,etc)(5)of the bridge real-time monitoring system is carried out,and the "random spectrum" of the response of daily random load is established.Researching the "three spectrum analysis method" based on the above "standard spectrum","theoretical spectrum" and "random spectrum",in order to judge preliminarily the actual operating conditions of bridge,and as a theoretical basis and database of real-time monitoring system for follow-up study.