Progressive Damage Modeling In Fiber-Reinforced Materials (original) (raw)
A three-dimensional progressive damage model for fibre-composite materials
Mechanics Research Communications, 2008
This note presents a damage model for fibre composite materials based in the approach by Matzenmiller et al. [Mat zenmiller, A., Lubliner, J., Taylor, R.L., 1995. A constitutive model for anisotropic damage in fiber composites. Mech. Mater. 20, 125]. In this work, the model is developed in a three dimensional context with modified formulation for the constitutive law and damage evolution. An orthotropic composite subjected to mixed failure modes is assumed in this development. Its formulation and implementation details are provided.
A Damage-Mode Based Three Dimensional ConstitutiveModel for Fibre-Reinforced Composites
Cmc-computers Materials & Continua, 2013
This article presents a three dimensional constitutive model for anisotropic damage to describe the elastic-brittle behavior of unidirectional fibrereinforced laminated composites. The primary objective of the article focuses on the three dimensional relationship between damage of the material and the effective elastic properties for the purpose of stress analysis of composite structures, in extension to the two dimensional model in Matzenmiller, Lubliner and Taylor (1995). A homogenized continuum is adopted for the constitutive theory of anisotropic damage and elasticity. Damage initiation criteria are based on Puck failure criterion for first ply failure and progressive micro crack propagation is based on the idea of continuum damage evolution. Internal variables are introduced to describe the evolution of the damage state under loading and as a subsequence the degradation of the material stiffness. Emphasis is placed on a suitable coupling among the equations for the rates of the...
Durability prediction of structural composites through a continuum damage mechanics approach
2010
The main objective of this research is to develop and implement a new analytical model that relies on a continuum-damage-mechanics approach to predict the evolution of plastic strain and mechanical damage until failure in a unidirectional fiber reinforced composite. The term "damage" is used only in the context of failure mechanisms associated with fracture, which are commonly associated with degradation in stiffness. Plastic and damage evolution are related to typical failure mechanisms in composite materials such as fiber, inter-fiber, and intra-fiber fracture. The plastic strain surface is defined based on the Tsai-Wu failure criterion, while the stiffness degradation damage surface is defined based on the energy-release crack growth. The coefficients that characterize the damage and the plastic surfaces are obtained from known material properties. Data obtained from inter-fiber shear load/unload experimental results are used to define the plastic and damage anisotropic associative evolution. The plastic and damage thresholds are obtained by using nonlinear extrapolation. The mathematical equations and physical principles underlying this model are formulated in the tensorial three-dimensional space and tailored to the primary objective of modeling damage evolution. This model is implemented as a new, user defined material in the commercial finite element analysis software ANSYS. The finite element results are validated by comparisons with published experimental data from shear load/unload in-plane tests, as well as with published experimental data from load/unload tension tests of a [±45°] 2S composite laminate. The comparison shows a good correlation between the model predictions and the experimental data. Finally, the new material model is implemented in ANSYS to predict the durability of a composite beam subjected to four-point bending, where the evolution of fiber, inter-laminar, and intra-laminar types of damage is quantified.
Composite Structures, 2015
A meso-scale material modeling of the fiber-reinforced polymer composites is presented. This model is based on coupled anisotropic viscoelasticity-viscoplasticity with anisotropic continuous damage mechanics. The constitutive equations are derived for three-dimensional statement and integrated implicitly by using return-mapping algorithm. Viscoelasticity model implies time dependent material properties. Viscoplasticity model is based on modified Hoffman criterion with combination of the Perzyna model. Anisotropic damage model is based on extended three-dimensional damage model. Developed material model is implemented in ABAQUS/Standard and is applied for modeling glass and carbon fiber laminate composite plates with various stacking sequences. Obtained results are in high agreement with already published experimental data.
Non-stationary progressive failure analysis of fiber-reinforced composites
This dissertation thesis focuses on the behavior of fiber-reinforced composite (FRC) materials. The main goal is to design an approach for the simulation of failure and damage of FRC materials and to implement this approach into a selected computer program. The basics of the behavior of composite materials, namely that of the unidirectional fiber-reinforced lamina, under the plane state of stress is studied. The most common theories for the prediction of local failure are presented and compared with the recent Puck's criterion. The non-stationary behavior of FRC materials is investigated using the theory of stress wave propagation in generally anisotropic three-dimensional solids with special focus on orthotropic materials and materials with hexagonal symmetry. An experiment was carried out to verify the theoretical results and an computational finite element analysis (FEA) model based on the theory. The response of a flat FRC panel on the in-plane impact of a glass spheric proj...
Computational Materials Science, 2010
A 3D anisotropic continuum damage model is developed for the computational analysis of the elastic-brittle behaviour of fibre-reinforced composite. The damage model is based on a set of phenomenological failure criteria for fibre-reinforced composite, which can distinguish the matrix and fibre failure under tensile and compressive loading. The homogenized continuum theory is adopted for the anisotropic elastic damage constitutive model. The damage modes occurring in the longitudinal and transverse directions of a ply are represented by a damage vector. The elastic damage model is implemented in a computational finite element framework, which is capable of predicting initial failure, subsequent progressive damage up to final collapse. Crack band model and viscous regularization are applied to depress the convergence difficulties associated with strain softening behaviours. To verify the accuracy of the damage model, numerical analyses of open-hole laminates with different lay-up configurations under tension and compression were performed. The numerical predictions were compared with the experimental results, and satisfactory agreement was obtained.
Composites Science and Technology, 2005
Constitutive damage models for fibre-reinforced composite materials should take into account the occurrence of the different damage mechanisms, their interaction and their influence on the resulting mechanical properties. Fibre breakage has usually been considered in damage models by means of deterministic failure criteria which thus leads to non-progressive behaviour or to a complete material collapse which is not realistic. This work presents a progressive damage model for fibre-reinforced composites based on the fragmentation analysis of the fibres. The stiffness loss of a unidirectional composite comes from the parameters of the Weibull distribution of the fibre strength and the mechanical properties of the fibre, matrix and the interface. The model has been developed for the initial stages of damage. The model is formulated in the framework of the mechanics of the continuous media. The constitutive model can be employed to simulate the contribution of fibres in damage models based on the rule of mixtures.
Modeling of Progressive Damage in High Strain—Rate Deformations of Fiber-Reinforced Composites
Major Accomplishments in Composite Materials and Sandwich Structures, 2009
We use the theory of internal variables, or equivalently of continuum damage mechanics, to develop a mathematical model involving three variables to describe the evolution of progressive damage in high strain-rate deformations of fiber-reinforced composites. The degradation of material parameters with the damage is considered. Values of material parameters in the postulated evolution laws of internal variables are determined from the test data. The delamination mode of failure is simulated by hypothesizing a damage surface in terms of transverse normal and transverse shear stresses acting on an interface between two adjoining layers. When the stress state at a point on an interface lies on this surface, delamination is assumed to ensue from that point. Initial-boundary-value problems are numerically solved to validate the mathematical model by comparing computed results with test findings. A Figure of Merit, equal to the percentage of work done by external forces dissipated by all failure mechanisms, is introduced to characterize the performance of laminated composites under shock loads.
An inelastic damage model for fiber reinforced laminates
Journal of composite materials, 2002
A new model for damage behavior of polymer matrix composite laminates is presented. The model is developed for an individual lamina, and then assembled to describe the nonlinear behavior of the laminate. The model predicts the inelastic effects as reduction of stiffness and increments of damage and unrecoverable deformation. The model is defined using Continuous Damage Mechanics coupled with Classical Thermodynamic Theory. Unrecoverable deformations and Damage are coupled by the concept of effective stress. New expressions of damage and unrecoverable deformation domains are presented so that the number of model parameters is small. Furthermore, model parameters are obtained from existing test data for unidirectional laminae, supplemented by cyclic shear stress-strain data. Comparison with lamina and laminate test data are presented to demonstrate the ability of the model to predict the observed behavior.
A new overall nonlinear damage model for fiber metal laminates based on continuum damage mechanics
Engineering Fracture Mechanics, 2018
Fiber Metal Laminates (FMLs) are hybrid composites made of interlacing layers of thin metal and fiber reinforced layers. In this work, a new overall damage model is developed to estimate the damage of FML considering the influence of stress triaxiality. The parameters of the damage model were determined using tensile test and iterative FE optimization for each sub-layer. Moreover, the stiffness degradation test was carried out to validate the proposed model for FML plain specimen. Additionally, notched FML specimens were used to simulate the material behavior under more complicated states of stress by implementing the proposed damage model in MSC MARC commercial FE code. A reasonable agreement was obtained between the FE and the experimental results for plain and notched FML specimens. The results indicated that the proposed model not only predicts the strong nonlinear behavior of plain and notched specimens, but also can estimate the failure strain with sufficient accuracy.