Analysis Of Mechanical Performance Of T-shaped Rigid Frame Bridge Based On Long-term Monitoring And Actual Bridge Test

With the steady development of my country’s comprehensive national strength and infrastructure construction,the daily traffic flow of bridges is gradually increasing.With vehicle loads as the main load,it has an irreversible impact on the bearing capacity and durability of the bridge.With the development of science and technology,from the beginning of regular inspections and maintenance measures to the current use of monitoring system sensors to monitor the bridge in real time,the overall structure and mechanical characteristics of the bridge are observed and recorded to achieve the effect of preventing inadequacy.In order to perform real-time monitoring and early warning of the main parameters of the overall structure and main components of the bridge during the operation of the bridge,the overall behavior of the bridge structure and the real-time environmental response can be monitored to realize the bridge service status,reliability,durability and bearing capacity.Evaluation provides basis and guidance for bridge maintenance and management decision-making.This article relies on an in-service bridge health monitoring system,through a series of issues such as the establishment of the health monitoring system,the analysis of monitoring data,the setting of early warning values,and the static load test,and the combination of software simulation and bridge load test data and monitoring data design.Pre-warning thresholds are set,and various parameters are given graded warnings,in order to provide a more effective and accurate data reference for the safe operation of the bridge.The main research contents are as follows:(1)Based on an in-service bridge project in Liaoning,the research background and significance are explained.The article finds out the development history of the bridge health monitoring system and the status quo at home and abroad by searching literature,and gives the shortcomings of the current monitoring system.(2)Establish a bridge health monitoring and early warning system that conforms to this project,and introduce the monitoring system from aspects such as the composition of the health monitoring system,the selection of sensors,data collection and transmission,the principles of establishing the monitoring system,and the principles of setting up measuring points.(3)The article uses the 2019 annual monitoring data as an example to describe the development trend of monitoring parameters such as vertical displacement,strain,and cracks,and analyzes the correlation and characteristics of each parameter to understand the annual changes and development of the bridge structure Trend and change range provide data support for the setting of early warning threshold of the monitoring system later.(4)Briefly explain the current situation of the early warning system,combine the literature to give the setting principles and methods of the early warning system,and set the early warning threshold for the strain,vertical displacement,cracks,temperature,and longitudinal displacement of the bridge structure.The setting of the early warning threshold is described in detail in combination with the monitoring data of the vertical displacement.Based on the monitoring data,relevant specification settings,and simulation data,the linear relationship between temperature and vertical displacement is analyzed,and the temperature effect is eliminated.For the influence of vertical displacement monitoring value,set the early warning threshold and set the grading early warning system.(5)Describe the static load test measuring point layout,loading method,data analysis and other aspects of the test bridge.Innovatively use the photoelectric deflection meter to collect the vertical displacement data of the load test,and use the load test to set an early warning for the previous article.Values are verified,and whether the early warning system can respond correctly,the accuracy of the early warning threshold and the reliability of the health monitoring system are tested.