Research On Performance Evaluation Of Prefabricated Simply Supported Beam Bridge Based On Load Test

Bridges are important basic facilities for people’s livelihood.Their excellent working performance is the key to maintaining smooth traffic.Therefore,it is necessary to evaluate the performance of existing bridges.Compared with other evaluation methods,the load test method is more accurate and intuitive,and the static load test is more mature.In recent years,due to the development of vibration theory and dynamic test instruments,the dynamic test of reinforced concrete bridge structures is carried out with precision and reliability.There has been a marked increase in sex,but a unified evaluation system has not yet been formed.Therefore,this paper mainly studies the static and dynamic load test to evaluate the overall performance of the bridge structure,and explores the method of evaluating the bridge structure by static and dynamic loads.In this paper,the first dimension analysis method is used to scale the bridge in accordance with 1:15 in the project,and the model single beam and model assembled simply supported beam bridge are obtained.Secondly,the self-vibration frequency test and static test of the single beam of the model are obtained.The modified finite element model is obtained by modifying the single beam of the model by the response surface correction method,and the single beam parameters are provided for the finite element analysis of the model assembled simply supported beam bridge.The ultimate bearing capacity test of the single beam of the model is carried out to verify the accuracy of the modified finite element model.The static test and dynamic test of the model-mounted simply supported beam bridge were carried out again.The purpose of the static test is to obtain the variation of the load lateral distribution coefficient and the lateral increase coefficient under different static load test conditions and different lateral contact damages;the purpose of the dynamic test is to obtain the fundamental frequency and the impact coefficient under different lateral contact damages.The change;and then assess the performance of the bridge.The results show that the fundamental frequency of the bridge after the horizontal contact damage is reduced,but the change is small;the variation law of the lateral distribution coefficient of the load is opposite to the change of the impact coefficient;the larger the difference of the transverse distribution coefficient of the load,the larger the lateral increase coefficient and the difference of the impact coefficient The larger the bridge,the weaker the horizontal connection of the bridge,and the worse its performance.In addition,on the basis of studying the static load test and the dynamic load test,a comprehensive evaluation index combining the static check coefficient and the impact coefficient is proposed.The results show that the comprehensive evaluation index can evaluate the performance of the bridge more objectively and comprehensively.Finally,based on the measured static data of the model structure and the prototype bridge,it is concluded that the relevant data obtained from the model structure can be used for the correlation analysis of the prototype bridge structure.