Analysis Of Functionally Graded Plates Subjected To Hygro-Thermo-Mechanical Loads

Reddy type higher-order shear deformation theory has been widely used in engineering practice,however,the transverse normal strain in Reddy 's theory was ignored,hygrothemal behaviors of functionally graded plates would not be analyzed accurately.In this paper,a Reddy type functionally graded plates theory which has considered transverse normal hygrothemal strain has been proposed,this theory has analyzed the hygrothemal behavior of functionally graded plates.Although this model has considered the transverse normal hygrothemal strain,extra displacement variation has not been increased.Based on this model,equilibrium equation and boundary conditions of FGM plates subjected to hygro-thermal-machanical loads has been deduced by means of the principle of minimum total potential energy,the solution of four-edges simply-supported FGM plates has been obtained by applying the Navier's theory.The stress and deformation obtained by this method were compared with the results of the other theories.The numerical results showed that the stress and deformation of the sinusoidal shear deformation theory,the exponential shear deformation theory,the higher-order shear deformation theory,the fifth-order shear deformation which ignored the transverse normal hygrothermal strain were not accurate,while the numerical results of this model were in good agreement with the solution.By analyzing the hygrothermal behaviors of FGM plates,the accuracy and efficiency of the proposed model were assessed.Moreover,the effects of temperature,moisture concentration,transverse normal strain,volume fraction distributions and side-to-thickness ratios on the displacements and the stresses of FGM plates have all been studied.