Test Research On Static & Dynamic Behavior Of Long-span Continuous Steel Box-girder Rigid Frame Tied-arch Bridge On Four-track Railway

In recent years, with the rapid development of railway field and the progressive implementation of leap forward development strategy,the railway passenger and freight car's running speed, loads, traction weight and number of organized group are increasing. In addition, new materials and new technologies are widely used in Railway Bridges, Load test is one of the most direct scientific methods to understand the working state of the bridge under actual operating load.Through static and dynamic load test of bridge structure, All aspects of measurement indexes and analysis of the evaluation results of the bridge structure can be obtained at the same time by real-time test and analysis , The final results can be used as a basis for the performance evaluation of the actual bridge. This paper based on a four-lane railway continuous steel box-girder rigid frame tied-arch bridge with main span arrangement 160m as an engineering background, The following aspects are discussed:Firstly,This dissertation introduces the basic theory of finite element analysis,the numerical Simulation of rigid frame tied arch bridge is established using finite element analysis software Midas/Civil,The deformation and stress of the bridge section are obtained through theoretical analysis of this model,the load conditions of the static load test in-situ,the location of the main control sections and measuring points are determined at the same time.Secondly, Through the bridge static load test,Strain and deflection of control section are tested under the different load case,The comparison between the measured data and the theoretical data shows that the measured data agree well with the theoretical values,finally we have obtained the bridge structure has enough strength and stiffness under static load.Thirdly,The bridge dynamic load test is carried out to test the natural frequency, dynamic deflection, dynamic stress, acceleration and dynamic displacement of the bridge, the measured values are compared with the theoretical values or norms, and we can get that the dynamic performance of the bridge structure under the train load is good.