Accession Number:

ADA285736

Title:

The Influence of Ply Waviness with Nonlinear Shear on the Stiffness and Strength Reduction of Composite Laminates

Descriptive Note:

Final rept. May 1992-Apr 1993

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Report Date:

1994-10-01

Pagination or Media Count:

38.0

Abstract:

The influence of ply waviness with nonlinear shear material response on the mechanical performance of composite laminates is studied. An analytic model, based on a three-dimensional laminated media analysis, is developed to predict the effective nonlinear laminate behavior associated with ply waviness. An undulating 0 ply in a 90090 sublaminate configuration and an undulating or - Beta ply in a 90 or - Beta90 sublaminate configuration are two types of ply waviness considered. An incremental loading strategy is employed wherein piecewise linear solutions are supposed to obtain the overall nonlinear stressstrain response of composite laminates with wavy plies. The analysis also predicts individual ply stress and strain distributions with the wavy ply configuration. The maximum stress failure criteria is used to predict ply failure in local regions with the wavy ply configuration, and a progressive failure methodology is adopted to permit local load redistribution. Results are presented which offer fundamental insight into the dominant mechanisms for stiffness and strength reduction in composite laminates exhibiting ply waviness and nonlinear shear material behavior. Composite materials, Ply waviness, Nonlinear shear, Stiffness, Strength.

Subject Categories:

  • Laminates and Composite Materials
  • Manufacturing and Industrial Engineering and Control of Production Systems
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE