Load Test Research Of High Pier And Large Span CFST Truss Bridge

Concrete filled steel tubular truss bridge is a relatively new bridge structure form with high bearing capacity, good ductility, excellent seismic performance, and convenient construction, which is well received by the engineers. Due to the complex bridge structure, as well as the drawbacks in the corresponding designs and construction regulations, it is necessary to conduct the whole bridge load test especially for the extra large bridge that can accurately reflect its quality and safety, which evaluates the security condition of the bridge structure according to a comparison of the test data and theoretical data, and also provides a basis for the complement of the similar bridge design theories and construction technology, helpful to the bridge maintenance and management, and extending its service life.On the basis of the domestic and international related research results, in the context of Yalu Expressway Ganhaizi Bridge’s construction, this paper researches the load test of the high pier and large span CFST Truss bridge from the following aspects:1、It establishes the Ganhaizi Bridge finite element model by the use of finite element analysis software MIDAS/Civil2010;2、It formulates the Ganhaizi Bridge static load test programme, determining the control section, loading mode, and loading position and tonnage. Also it tests the section stress and girder deflection under static loading conditions comparing the theoretical data. The test result shows that the design is reasonable and the bridge structure has sufficient strength and rigidity.3、It organizes the Ganhaizi Bridge dynamic load test programme to analyse the finite element model, obtaining the theoretical natural frequency of vibration and vibration mode. In the dynamic load experiment, the author tests the bridge vibration characteristics and damping ratio, and carries out a series of tests on driving, bumping, and braking excitation, which analyses the impact effect of the bridge structure under various vibration. The test result shows that the bridge has a good dynamic performance.