Multi-scale dynamic failure prediction tool for marine composite structures |
| |
Authors: | James Lua William Gregory Jagannathan Sankar |
| |
Affiliation: | (1) Applied Mechanics Department, Anteon Corporation, SEG/Engineering Technology Center, 240 Oral School Road, Suite 105, Mystic, CT 06355-1208, USA;(2) Anteon Corporation, SEG/Engineering Technology Center, 1100 New Jersey Avenue, SE Suite 200, Washington, DC 20003, USA;(3) Center for Advanced Materials and Smart Structures, NC A&T State University, 1601 E. Market Street, Greensboro, NC 27411, USA |
| |
Abstract: | A high fidelity assessment of accumulative damage of woven fabric composite structures subjected to aggressive loadings is
strongly reliant on the accurate characterization of the inherent multi-scale microstructures and the underlying deformation
phenomena. Damage in composite sandwich and joint structures is characterized by the coexistence of discrete (delamination)
and continuum damage (matrix cracking and intralaminar damage). A purely fracture mechanics-based or a purely continuum damage
mechanics-based tool alone cannot effectively characterize the interaction between the discrete and continuum damage and their
compounding effect that leads to the final rupture. In this paper, a hybrid discrete and continuum damage model is developed
and numerically implemented within the LS-DYNA environment via a user-defined material model. The continuum damage progression
and its associated stiffness degradation are predicted based on the constituent stress/strain and their associated failure
criteria while the discrete delamination damage is captured via a cohesive interface model. A multi-scale computational framework
is established to bridge the response and failure predictions at constituent, ply, and laminated composite level. The calculated
constituent stress and strain are used in a mechanism-driven failure criterion to predict the failure mode, failure sequence,
and the synergistic interaction that leads to global stiffness degradation and the final rupture. The use of the cohesive
interface model can capture the complicated delamination zone without posing the self-similar crack growth condition. The
unified depiction of the continuum and discrete damage via the damage mechanics theory provides a rational way to study the
coupling effects between the in-plane and the out-of-plane failure modes. The applicability and accuracy of the damage models
used in the hybrid dynamic failure prediction tool are demonstrated via its application to a circular plate and a composite
hat stiffener subjected to shock and low velocity impact loading. The synergistic interaction between the continuum and discrete
damage is explored via its application to a sandwich beam subjected to a low velocity impact. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|