skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Galerkin projection for geometrically-exact multilayer beams allowing for ply drop-off

Conference ·
OSTI ID:175463
;  [1]
  1. Univ. of Flordia, Gainesville, FL (United States)

Focusing on the static case in the present work, we develop a Galerkin projection of the resulting nonlinear governing equations of equilibrium for geometrically exact sandwich beams and 1-D plates developed. In the proposed theory, each layer in the beam can have different thickness and length. As such one can use the present formulation to model an important class of multilayer structures having ply drop-off. No restriction is imposed on the magnitude of the displacement field, whose continuity across the layer interfaces is exactly enforced. The layer cross section in the deformed beam is assumed to remain straight, but not orthogonal to the layer centroidal line, thus shear deformation in each layer is accounted for. Also no restriction is imposed on the rotation of a layer cross section. It follows that the overall cross section in the deformed beam is continuous piecewise linear, and can be best thought of as a chain of rigid links, connected by hinges. The overall deformation of a multilayer beam can be described by the deformation of a reference layer. The unknown kinematic quantities are therefore the two displacement components of the deformed centroidal line of a reference layer, and the finite rotations of the layers. The present theory can be used to analyze large deformation in sandwich beams. Numerical examples, such as roll-up maneuver and sandwich beam with ply drop-off, which underline the salient features of the formulation are presented. Saint-Venant principle is demonstrated for very short sandwich beams. The readers are referred to the paper for detail.

OSTI ID:
175463
Report Number(s):
CONF-950686-; TRN: 95:006111-0474
Resource Relation:
Conference: Joint applied mechanics and materials summer meeting, Los Angeles, CA (United States), 28-30 Jun 1995; Other Information: PBD: 1995; Related Information: Is Part Of AMD - MD `95: Summer conference; PB: 520 p.
Country of Publication:
United States
Language:
English

Similar Records

A multi-director finite element shell theory for composite laminates
Conference · Sun Dec 31 00:00:00 EST 1995 · OSTI ID:175463

Stiffness matrix for beams with shear deformation and warping torsion
Conference · Sun Dec 31 00:00:00 EST 1995 · OSTI ID:175463

3-D stress analysis of cross-ply laminated composites
Journal Article · Thu Sep 01 00:00:00 EDT 1994 · Journal of Energy Resources Technology; (United States) · OSTI ID:175463