Static And Dynamic Load Test And Analysis Of The Ultimate Load Of Heterotype Steel Truss Bridge

Taking a steel truss bridge as the engineering background,the static and dynamic load test of the steel truss bridge is carried out and the bearing capacity of the bridge is checked.The parameters of the original finite element model were calibrated by using the static and dynamic load test results and Kriging model.Finally,the calibrated finite element model is used to analyze the ultimate bearing capacity of bridge structure.The purpose of this thesis is to evaluate the safety and bearing capacity of bridge structures by combining theoretical research,numerical simulation and static and dynamic load tests.The main research contents and conclusions of this thesis include:1.The finite element analysis software Midas/Civil was used to complete the static and dynamic analysis of the bridge structure.According to the results,the static and dynamic load test scheme was designed,including determining the arrangement of measuring points,and load cases.The static load data and dynamic characteristic data of the bridge under different load cases are obtained by the static and dynamic load tests.The comparison and analysis of the field test data with the finite element calculated data and the relevant specification values show that the performance of the bridge satisfy the specification requirements.2.The Kriging model between structural parameters and structural responses is established by using the data of the ambient vibration test.The Kriging model was used to calibrate the original finite element model,and then the accuracy of the updated finite element model was checked using the static test data.The results show that the calculated results based on the updated model is close to the field test results.3.The instability coefficient is obtained by the linear elastic buckling analysis,and the structural stability safety coefficient is obtained by combining with the nonlinear theory,which takes into account geometric nonlinearity,material nonlinearity and geometric-material double nonlinearity effect.Then the influence of the material strength and section size on the ultimate bearing capacity of the bridge is studied.