Damage mechanism-based multiscale model for dynamic failure of textile composites
Abstract
This study is focused on the continuum scale modeling of crack branching and damage mechanism transitions that occur during dynamic fracture of textile composites. Specifically, the aim is to understand the numerical considerations that underpin objective and accurate predictions in this regard, and analyze the role played by localization limiters such as the crack band model, and material rate dependence. For this purpose, a strain rate dependent multi-scale constitutive model which is organized based on damage-mechanisms will be developed. The model will be formulated in the framework of the microplane theory, which models various damage mechanisms at lower length scales in terms of local stress-strain vectors. Compared to conventional continuum damage models based on tensors, this lends the model a better resolution in terms of damage mechanisms and the potential ability to predict transitions of damage mechanisms during crack branching. Primary damage mechanisms observed in textile composites will be considered in the formulation. These include tensile fiber breaking, compressive fiber kinking, matrix microcracking and interlayer delamination. Various phenomena lending a strain rate dependence to the mechanical and fracturing behavior will be formulated. These include viscoelasticity, rate effects in crack opening stemming from the activation energy of fracture growth, inertial & stress wave effects. The model will capture the evolution of global damage by homogenization of various individual subscale damage states. The model will be benchmarked and validated against a wide range of available test data, and subsequently used to analyze the strain rate dependent crack branching and damage mode transitions in composites. Various relevant predictions such as crack speeds, geometry of crack branching, and energy dissipation will be evaluated under general multi-axial dynamic loads. This study will also aim to identify applicability and limitations of the continuum modeling approach for dynamic fracture, and outline conditions that warrant discrete modeling approaches or inclusion of additional physical phenomenon that were possibly unaccounted for so far. It is anticipated that this study will lead to the development of a reliable constitutive model, which can capture the dynamic crack branching and damage mode transitions at continuum scale. The model will be applicable to a variety of textile composites (i.e. 2D/3D woven, braided etc.) and will be a valuable tool for designing composite structures for reliable protection of personnel and infrastructure against impact/blast loads.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 20, 2019
- Source ID
- W911NF1910312
Entities
People
- Kedar Kirane
Organizations
- Army Contracting Command
- Research Foundation for the State University of New York
- United States Army