Submatrix approach to stiffness matrix correction using modal test data

Abstract

An efficient method six stiffness matrix correction to match modal testing data is presented. Significant reduction of unknown parameters is achieved by grouping the elements of the same stiffness characteristics and representing them as a multiplication of a scaling factor and a submatrix. A concise formulation to identify the scaling factors is found by utilizing a least squares solution. The formulation also incorporates a capability of reducing finite element mass and stiffness matrices to test degrees-of-freedom for a direct analysis/experiment correlation