Curved Sandwich Panels Subjected to Temperature Gradient and Mechanical Loads

The results of a detailed study of the nonlinear response of curved sandwich panels with composite face sheets, subjected to a temperature gradient through the thickness combined with mechanical loadings, are presented. The analysis is based on a first-order shear-deformation Sanders-Budiansky-type theory, with the effects of large displacements, moderate rotations, transverse shear deformation, and laminated anisotropic material behavior. A mixed formulation is used with the fundamental unknowns consisting of the generalized displacements and the stress resultants of the panel. The nonlinear displacements, strain energy, principal strains, transverse shear stresses, transverse shear strain energy density, and their hierarchical sensitivity coefficients are evaluated. The hierarchical sensitivity coefficients measure the sensitivity of the nonlinear response to variations in the panel parameters, the effective properties of the face sheet layers and the core, and the micromechanical parameters. Numerical results are presented for cylindrical panels subjected to combined pressure loading, edge shortening or extension, edge shear, and a temperature gradient through the thickness. The results show the effects of variations in the loading and the panel aspect ratio, on the nonlinear response, and its sensitivity to changes in the various panel, effective layer, and micromechanical parameters.

[1]  Nicholas J. Hoff Monocoque, sandwich, and composite aerospace structures , 1986 .

[2]  G.A.O. Davies,et al.  Buckling and postbuckling of composite structures , 1995 .

[3]  Ahmed K. Noor,et al.  Assessment of continuum models for sandwich panel honeycomb cores , 1997 .

[4]  Liviu Librescu,et al.  Post-buckling of geometrically imperfect shear-deformable flat panels under combined thermal and compressive edge loadings , 1993 .

[5]  Ahmed K. Noor,et al.  Finite element buckling and postbuckling solutions for multilayered composite panels , 1994 .

[6]  Ahmed K. Noor,et al.  Reduced basis technique for calculating sensitivity coefficients of nonlinear structural response , 1992 .

[7]  Ahmed K. Noor,et al.  Recent advances in reduction methods for instability analysis of structures , 1983 .

[8]  Ahmed K. Noor,et al.  Mixed models and reduced/selective integration displacement models for nonlinear shell analysis , 1982 .

[9]  Liviu Librescu,et al.  THERMOMECHANICAL POSTBUCKLING OF GEOMETRICALLY IMPERFECT FLAT AND CURVED PANELS TAKING INTO ACCOUNT TANGENTIAL EDGE CONSTRAINTS , 1995 .

[10]  C. W. Bert,et al.  Shear deformation and sandwich configuration , 1995 .

[11]  Ahmed K. Noor,et al.  Computational Models for High-Temperature Multilayered Composite Plates and Shells , 1992 .

[12]  D. E. McFarland,et al.  Analysis of plates , 1972 .

[13]  Ahmed K. Noor,et al.  Computational Models for Sandwich Panels and Shells , 1996 .

[14]  Ahmed K. Noor,et al.  Multiple‐parameter reduced basis technique for bifurcation and post‐buckling analyses of composite plates , 1983 .

[15]  M. Ashby,et al.  Cellular solids: Structure & properties , 1988 .

[16]  J. Aboudi Mechanics of composite materials - A unified micromechanical approach , 1991 .

[17]  Ahmed K. Noor,et al.  Thermomechanical postbuckling of multilayered composite panels with cutouts , 1995 .

[18]  Ahmed K. Noor,et al.  Stiffness and thermoelastic coefficients for composite laminates , 1992 .

[19]  Ahmed K. Noor,et al.  Thermomechanical buckling and postbuckling of multilayered composite panels , 1993 .

[20]  S. Tsai,et al.  Introduction to composite materials , 1980 .