Boundary element method based sensitivity analysis of the crack detection in beams

Abstract

A sensitivity analysis of natural frequencies to detect defects in beams is presented. The performance of the Boundary element method (BEM) as a means of the forward problem solver is compared with that of the Finite element method (FEM) with massless rotational spring model. Experimentally measured natural frequencies are input as the reference frequencies. As for the crack cases considered in the present study BEM shows better performance than FEM with massless rotational spring model. Because all the computations are restricted to the boundary BEM is particularly useful when subsequent changes in the meshes are made, which makes it ideal for the defect detection problem that requires the re-meshing many times. BEM may be an alternative to FEM with massless rotational spring model in the defect detection of a beam.