Research On Control Load Of Reinforced Concrete Beam Bridge In Static Load Test

In recent years,with the rapid development of China’s social economy,the transportation industry has risen rapidly.In order to adapt to the huge traffic volume,infrastructure constructions such as highways and bridges are very rapid.By the end of 2017,the number of highway bridges in China had reached more than 800,000,with a total length of more than 50 million linear meters.The increasing demand for freight forwarding puts forward higher requirements for the safety operation level of in-service bridges.The load-bearing capacity of the bridge structure is attenuated to varying degrees with the increase of use time,so the evaluation of the structural safety performance is particularly important.Bridge static load test is the main method for structural analysis and evaluation,but the method of determining the control load in static load test is relatively simple at present.Based on the analysis of structural reliability theory and reinforced concrete beam bridge,this paper studies the control load of static load test and proposes a method to determine the control load of static load test considering different safety levels.The main research contents are as follows:(1)The status of bridge service at home and abroad is introduced,the significance of research on control load of static load test is expounded,and the achievements of static load test research in recent years by industry personnel are summarized.(2)The system introduces the load-limiting analysis method of reinforced concrete bridge,and the calculation method of load effect in static load test is explained in detail,A method of estimating the load effect limit of vehicles under different safety levels as the control load for static load test is proposed.(3)Select a reinforced concrete beam bridge in Shandong Province for static load test.The design load required by the current code is used as the test control load,and the static load test efficiency is used to ensure the test effect.The space finite element software Midas was used to establish the model,and the structural safety is analyzed by combining the experimental data and theoretical calculation.(4)Modify the initial model according to the field test data,and conduct control simulation based on the vehicle load effect limits calculated by the three load-limiting safety levels,and further analyze the safety of the structure when the proposed control load is subjected to the simulation test.The research shows that for the simply-supported reinforced concrete beam bridge in service,it is safe and reasonable to determine the control load when carrying out the static load tests on the bridge structures of different safety grades under the influence of resistance correction coefficient and the ratio of live dead load.