Fei Qingguo

College of Civil Engineering,

Southeast University,

Nanjing 210096,China

Zhang Lingmi

Guo Qintao
College of Aerospace Engineering,

Nanjing University of Aeronautics 

and Astronautics,

Nanjing 210016, China

Abstract: Finite element model updating method based on global information is proposed. Prior investigation upon design space of structural parameters is performed before updating using statistic analysis, including parameter screening using variance analysis and response surface fitting using regression analysis. The parameter screening method selects the design parameters considering the result of hypothesis testing, which is a kind of global information. Meanwhile, the traditional updating method considers local sensitivity which only gives the information at sole point in the design space. Response surface fitting constructs a close-form multinomial which describes the relationship between concerned structural feature and selected updating parameters. It is an approximation to finite element models (FEM) and used as a substitution in the updating iterations. The presented updating method can be applied without the restriction of linear assumption. In addition, there is no data exchange between the updating program and the finite element analysis program in the updating iterations. This makes the method practical in engineering. An aircraft test structure, GARTEUR, is employed to verify the effectiveness of the method. After updating, the error of modal frequencies is less than 3%.

Key words: Model updating  Design of experiment  Variance analysis  Regression analysis Response surface methodology