Finite Element Model Updating and Dynamic Design of Spot Welded Structures

Abstract

Spot welds are used extensively in the automotive industry to join panels and for construction of other subassemblies that contains several thousands of spot-welds, so it is not practical in structural analysis to model each and every spot weld joint in detail. So a simple Finite element (FE) model of spot-welds needs to be used. There is not much work reported on dynamic testing, correlation and updating of the spot welded structures. This work explores the use of FE model updating to improve the dynamic characteristics of the spot welded structures. A hat like structure, used in earlier studies, is built and experimental modal analysis done on the spot welded structure. An FE model for the hat structure is built and correlated mode pairs are identified and attempts are made to update the FE model. Structural dynamic modification studies have been carried out to evaluate the effectiveness of the updated FE model of the spot welded structure for dynamic design. It is found that the updated FE model predicts more accurately the changes in dynamic characteristics as compared to the original FE model. Effect of spot welds on natural frequencies and damping of the spot welded structures is also studied.KeywordsSpot WeldingSpot WeldDynamic DesignExperimental Modal AnalysisSimple Finite ElementThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.