제진재의 물성치를 이용한 등가물성치 산출에 관한 연구

This paper presents the study of equivalent material properties with visco-elastic material properties.. The goal of the study is anticipation of equivalent material properties (natural frequency, loss factor, and Young's modulus) in damping materials treatment. Through the equivalent material properties, we must design FEM model with constrained layer damping material. And equivalent material properties saved solving time in FEM model. We could acquire the visco-elastic material properties (shear modulus, loss factor) to experiment the oberst test using modified ASTM. And we can anticipate resonance of constrained beam with shift ratio between bare beam and constrained beam. Equivalent material properties of constrained beam is obtained from shear parameters (g is made of shear modulus of visco-elastic material, length, and wave number) at resonance of constrained beam. FEM model of visco-elastic material must be designed solid model. We didn't design solid FEM model but equivalent shell FEM model. So we saved solving time and convenience of FEM model mesh.