Structural Integrity Associates, San Jose, CA
University of Illinois, Urbana, IL
Pages: 30 Published: Jan 1985
The research herein develops an accurate and efficient numerical technique, finite-element method with hybrid stress crack-tip elements, for analyzing interfacial crack problems under dynamic loading. Hybrid stress crack-tip elements for interfacial cracks of composite laminates are formulated by setting the first variation of a hybrid functional equal to zero. During the element formulation, asymptotic solutions around the crack tip are employed for stress and displacement fields within the crack-tip element. Displacements along element boundaries are interpolated independently. Newmark's θ method is used for integrating dynamic equations. Thus, monotonic convergence of the finite-element solutions is guaranteed. Two different kinds of delaminations, open and closed interfacial cracks, under lateral impact are studied. Effects of element size, element aspect ratio, and eigenfunction truncation have been investigated. Transient solutions for (± θ) composites are presented for illustration. Effects of crack sizes and lamination sequences are discussed.
stress-intensity factor, strain energy release rate, linear elastic fracture mechanics, finite-element model, dynamic fracture mechanics, anisotropy, composite materials
Paper ID: STP36297S