Strategy of crack identification for continuum structure based on Kriging surrogate model

A method of crack identification is presented based on the Kriging surrogate model.The initial samples are used to construct the initial Kriging model establishing the relationship between the crack parameters and the corresponding structural dynamic responses instead of bewteen the dynamical input and output and thereby avoiding either the re-meshing process at every iterative step of optimization or the time-consuming finite element calculation.To improve the accuracy of the surrogate model,an optimal point-adding process is carried out to reduce the computational cost.For identifying crack parameters based on the constructed Kriging model,a robust stochastic particle swarm optimization(SPSO)algorithm is applied to enhance the global searching ability.Numerical studies for a cantilever beam and a plate having a respective crack are performed.The effectiveness and noise immunity of this method are demonstrated by the identification results.In addition,the effects of initial sampling size on the identification efficiency and the precision of the identification results are also investigated.