An experimental study on the structural behavior and vibrational characteristic of FRP-sandwitch plate with unsymmetrical face

초록

Sandwitch elements are characterized with high flexural rigidity/strength for low density ratio,and excellence in anti-vibration and anti-noise.These properties are very useful in building airplanes and high-speed ships,which require lighter and high strength elements. In this study,the Reissner-Mindlins shear deformation and rotary inertia plate theory were applied for rectangular sandwitch models,expanded from the Hamiltons principle.This paper shows results of the equation of motion on the Hamiltons principle and comparision with those of Rayleigh-Ritz metod obtained by energy relationships.The results are compared with simulation data obtained from NISA(Numerical Intergration Elements for System Analysis,Finite Element Method Package Program). The applied sandwitch models have isotropic and unsymmetrocal faces and istropic core. It consists of five plate of different utility and thickness. They are commonly used as structural elements of surface effect ships(SES).The boundary conditions considered in the research are simple supports.Youngs modulus and shear modulus are derived from 4-point bending test for sandwitch beam.