Finite element implementation of delamination in composite plates

Modelling of composite structures is limited by finite element (FE) codes to effectively model certain critical failure modes, such as delamination. Previous efforts to model delamination and debonding failure modes using FE codes have typically relied on ad hoc failure criteria and quasi-static fracture data. Improvements to these modelling procedures can be made by using an approach based on fracture mechanics. A study of modelling delamination using the finite element code ANSYS was conducted. This investigation demonstrates the modelling of composites through improved delamination modelling. Further developments to this approach may be improved

Finite element implementation of delamination in composite plates

Modelling of composite structures is limited by finite element (FE) codes to effectively model certain critical failure modes, such as delamination. Previous efforts to model delamination and debonding failure modes using FE codes have typically relied on ad hoc failure criteria and quasi-static fracture data. Improvements to these modelling procedures can be made by using an approach based on fracture mechanics. A study of modelling delamination using the finite element code ANSYS was conducted. This investigation demonstrates the modelling of composites through improved delamination modelling. Further developments to this approach may be improved

Programming of composite plates damage calculation

The goal of this paper is to present the numerical results of elastic damage of thin unidirectional fiber-reinforcedcomposite plates. The numerical implementation uses a layered shell finite element based on the Kirchhoff plate theory. Newton-Raphson method is used to solve the system of nonlinear equations and evolution of damage has been solved using return-mapping algorithm. The analysis is performed by finite element method and user own software is created in MATLAB programming language. One problem for two different materials was simulated in order to study the damage of laminated fiber reinforced composite plates.The goal of this paper is to present the numerical results of elastic damage of thin unidirectional fiber-reinforced composite plates. The numerical implementation uses a layered shell finite element based on the Kirchhoff plate theory. Newton-Raphson method is used to solve the system of nonlinear equations and evolution of damage has been solved using return-mapping algorithm. The analysis is performed by finite element method and user own software is created in MATLAB programming language. One problem for two different materials was simulated in order to study the damage of laminated fiber reinforced composite plates

Meshless Modelling of Laminate Mindlin Plates under Dynamic Loads

Collocation method and Galerkin method have been dominant in the existing meshless methods. A meshless local Petrov-Galerkin (MLPG) method is applied to solve laminate plate problems described by the Reissner-Mindlin theory for transient dynamic loads. The Reissner-Mindlin theory reduces the original three-dimensional (3-D) thick plate problem to a two-dimensional (2-D) problem. The bending moment and the shear force expressions are obtained by integration through the laminated plate for the considered constitutive equations in each lamina. The weak-form on small subdomains with a Heaviside step function as the test functions is applied to derive local integral equations. After performing the spatial MLS approximation, a system of ordinary differential equations of the second order for certain nodal unknowns is obtained. The derived ordinary differential equations are solved by the Houbolt finite-difference scheme as a time-stepping method

Numerical Finite Element Method Homogenization of Composite Materials Reinforced With Fibers

The paper presents the micromechanical modelling of fiber-reinforced composites in order to determine elastic properties of the homogenized material. For this purpose implementation of homogenization theory was required and analyses were performed. The polymer matrix of three-dimensional representative volume element (RVE) of the composites is modelled by the finite element method (FEM). Software for homogenization of material properties uses direct homogenization method which is based on volume average of stresses in the RVE. Homogenization of composite plate is performed by linking MATLAB and ANSYS software. Calculated elastic properties of the homogenized material are given for epoxy matrix reinforced with carbon, fiberglass and kevlar fiber material

FINITE ELEMENT IMPLEMENTATION OF DELAMINATION IN COMPOSITE PLATES

Modelling of composite structures by finite element (FE) codes to effectively model certain critical failure modes such as delamination is limited. Previous efforts to model delamination and debonding failure modes using FE codes have typically relied on ad hoc failure criteria and quasi-static fracture data. Improvements to these modelling procedures can be made by using an approach based on fracture mechanics. A study of modelling delamination using the finite element code ANSYS was conducted. This investigation demonstrates the modelling of composites through improved delamination modelling. Further developments to this approach may be improved

Failure of Composites with Short Fibers

Strength-based failure criteria are commonly used with the finite element method (FEM) to predict failure events in composite structures. The laminate analogy is very useful for the calculation of the strength of composite materials with short fibers. The prediction of the laminate strength is carried out by evaluating the stress state within each layer of the laminate based on the classical lamination theory. In this paper FEM is used as a tool to predict the laminate strength. Failure criteria are used to calculate a failure index (FI) from the computed stresses and user-supplied material strengths. The micromechanical analysis has been carried out using computer package MATLAB and numerical simulation has been executed by using a commercially available ANSYS code