tailieunhanh - Thermoelastic stability of thick imperfect functionally graded plates

This paper investigates buckling of thick functionally graded plates with initial geometrical imperfection under thermal loadings. The equilibrium, stability, and compatibility equations of an imperfect functionally graded plate are derived using the third order shear deformation theory. | Vietnam Journal of Mechanics, VAST, Vol. 32, No. 1 (2010), pp. 47 – 58 THERMOELASTIC STABILITY OF THICK IMPERFECT FUNCTIONALLY GRADED PLATES Hoang Van Tung1 , Nguyen Dinh Duc2 1 Hanoi Architectural University, Vietnam 2 Vietnam National University, Hanoi Abstract. This paper investigates buckling of thick functionally graded plates with initial geometrical imperfection under thermal loadings. The equilibrium, stability, and compatibility equations of an imperfect functionally graded plate are derived using the third order shear deformation theory. Material properties are assumed to be temperatureindependent and graded in the thickness direction according to a simple power law distribution in terms of the thickness coordinate variable. By Galerkin method, the resulting equations are solved to obtain closed-form solutions of critical buckling temperature difference. Two types of thermal loading, uniform temperature rise and nonlinear temperature change across the thickness are considered. Buckling analysis for a simply supported rectangular imperfect functionally graded plate shows effects of geometry and material parameters, shear deformation and imperfection on critical buckling temperature. 1. INTRODUCTION By high performance heat resistant capacity, Functionally Graded Materials (FGMs) have received much attention for structural applications in ultrahigh temperature environments and extremely large temperature gradient such as aircraft, space vehicles, nuclear plants, and many other applications. By varying smoothly and continously of mechanical properties from one surface to the other, FGMs eliminates interface problems and stress concentrations. Javaheri and Eslami reported mechanical and thermal buckling of rectangular functionally graded plates by using the classical theory [2, 3] and the third order shear deformation theory [4, 5]. They used energy method to derive governing equations that are analytically solved to obtain the closed-form solutions of .