Modal test method of concrete-filled steel tubular arch bridge model and its application

Structural dynamic analysis which takes the structural modal parameter as its basis is one of key problems of dynamic analysis of bridge structure.Firstly,a finite element model was set up for a concrete-filled steel tubular arch bridge,its dynamic analysis was carried out.Then a modal test was conducted and the first six order modes and frequencies of this structure were identified by using Eigen-system Realization Algorithm(ERA) combined with Natural Excitation Technique(NEXT).Finally it was known from the comparison of test result to the result of finite element computation that further finite element model updating would be necessary for this kind of complex structure.