QUASI-GREEN'S FUNCTION APPROACH TO FUNDAMENTAL FREQUENCY ANALYSIS OF ELASTICALLY SUPPORTED THIN CIRCULAR AND ANNULAR PLATES WITH ELASTIC CONSTRAINTS

摘要

Free vibration analysis of homogeneous and isotropic thin circular and annular plates with discrete elements such as elastic ring supports is considered. The general form of quasi-Green's function for thin circular and annular plates is obtained. The nonlinear characteristic equations are defined for thin circular and annular plates with different boundary conditions and different combinations of the core and support radius. The continuity conditions at the ring supports are omitted based on the properties of Green's function. The fundamental frequency of axisymmetric vibration has been calculated using the Newton-Raphson method and calculation software. The obtained results are compared with selected results presented in literature. The exact frequencies of vibration presented in a non-dimensional form can serve as benchmark values for researchers to validate their numerical methods when applied for uniform thin circular and annular plate problems.