Effect of lumped mass on the structural dynamic modifications of a structure

Abstract

Abstract The identification of the effectdue to structural changes using modal data is very challenging in the structural dynamic modifications (SDM) study. In this paper, the aim of this studyis to identifythe effect of physical changes of a structural system based on the natural frequencies and mode shapes. A mild steel thin plate structure was used in the study. A mass was attached to the thin plate to alter the dynamic characteristics of the thin platestructure. Experimental modal analysis (EMA) and the normal modes analysis wereperformed in two stages to the thin plate structure, without mass and the mass is attached to the thin plate structure. The normal modes of the thin plate structure were obtained using finite element (FE) analysis. The results of the natural frequencies and mode shapes between the thin plate and thin plate with SDM were compared. It is concluded that the impact of structural changes due to SDM will change the modal parameters of the structure.