Aug 2026· International Journal for Numerical Methods in Engineering· Vol 127· 0 citations· 41 references
Abstract
This paper presents a study on multi‐scale modelling of progressive damage model in laminated composites using shell finite elements, with considerations for the effects of manufacturing defects. The approach utilises second‐order homogenisation with 5‐parameter shell formulation to capture the effects of complex sub‐structural geometry and damage mechanisms in a smeared, equivalent single layer manner. During analysis, the shell constitutive tensors are continually updated and derived from high‐fidelity unit cell simulations. The key benefits are two‐fold. First, manufacturing defects can be directly introduced to targeted regions by assigning unit cells containing said defects. Second, the effects of progressive damage, including delamination, are accounted for in a smeared fashion without requiring complex mesh‐stacking nor discontinuous kinematic enhancements. A series of numerical benchmarks are presented to demonstrate the model's ability to accurately predict damage/defect induced stiffness degradation, failure loads and damage morphology in laminated composites under loading conditions, including bending, shear, buckling and static indentation. Overall, the findings in this paper presents a proof‐of‐concept for a multi‐scale framework that enables defect assessment and damage modelling in shell‐based simulations of composite structures, and lays the groundwork for future computational acceleration via surrogate modelling.
Homogeneous TC4 titanium alloy suffers from the strength–ductility trade-off and exhibits insufficient anti-penetration capacity under high-strain-rate impact. TiCp-reinforced functionally graded titanium matrix composites (FGTMCs) with a “hard outer, tough inner” gradient architecture are promising lightweight armor materials. The use of Abaqus/Explicit finite element simulation for FGTMCs under dynamic impact can capture transient deformation and damage evolution while enabling rapid evaluation of the impact resistance of different materials; however, research in this area remains scarce. This study conducts a systematic parametric analysis of key simulation parameters, including calibration of the Johnson–Cook constitutive and damage model parameters for TC4 titanium alloy, optimization of mesh partitioning strategies, hourglass control schemes, model dimensions, and boundary conditions to suppress “ghost mesh” numerical artifacts. Material property assignments for TC4 and three typical titanium matrix composites are designed, along with a methodology for constructing functionally graded material models. Two projectile–target matching configurations (small projectile/thin target vs. large projectile/thick target) are compared, and the optimal model of a 700 m/s small-caliber tungsten projectile impacting a 50 mm TC4 target is identified. Parametric analysis demonstrates that a damage parameter D4 = 0.1 significantly improves numerical stability, and a graded mesh strategy with further refinement along the penetration path balances computational accuracy and efficiency. Using the optimized material system, the simulation results reproduce the three-stage damage evolution of titanium alloys under impact—cratering, plastic penetration, and back-face spallation—providing reliable numerical support for the structural optimization of graded armor materials.
Carbon Fiber Reinforced Polymer (CFRP) composites have become indispensable in the aerospace industry due to their superior mechanical properties. Delamination, often initiated by impact events, manufacturing defects or fatigue loading, reduces the stiffness and structural integrity of the structure. In actual structures delamination can propagate through multiple plies, causing both interlaminar and intralaminar fractures. Conventional finite element approaches, such as virtual crack closure technique (VCCT) and cohesive zone modelling (CZM), are inadequate for modelling both interlaminar and intralaminar failures. The purpose of this paper is to explain how to overcome these limitations by integrating the Extended Finite Element Method (XFEM) with cohesive zone surface‐based modelling. A comprehensive numerical model capable of accurately predicting both interlaminar and intralaminar crack propagation in multiangular CFRP composites under Mode‐1 loading is presented. Details of numerical modelling of various delamination interfaces and its comparison with experimental data are presented.
Mohan R. Krishna, Siddharth J. M. T. Selvan, Shubham Kumar et al.· Macromolecular Symposia· 0 citations
This study aims to numerically investigate the mode I, II, and III fracture behaviors of additively manufactured degradable, bioplastic polylactic acid (PLA) lattice specimens. Numerical simulations were performed using the eXtended Finite Element Method (XFEM) based on the extracted PLA's mechanical and fracture material properties. The maximum principal stress and fracture energy power‐law criteria were utilized to simulate damage initiation and evolution in three‐dimensional (3D) numerical analyses. To consider the effects of build orientation, the transversely isotropic elasticity model (TIEM) was implemented. To facilitate the XFEM analyses, the equivalent solid material model (ESMM) technique was also utilized. The experimental load‐displacement responses of single‐edge notched bending specimens under the symmetric and asymmetric four‐point bending and mode III transverse shear cracked plate tests were conducted for comparison with the XFEM analyses in mode I, II, and III fracture, respectively. A common calibration factor, as well as the simultaneous utilization of the TIEM model, as well as the XFEM and ESMM techniques, reflected numerical results of acceptable accuracy compared to the experimental results; 5.3% (3.4%), 4.4% (5.8%), and 9.6% (5.4%) differences for the stiffness (peak load) of mode I, II, and III specimens, respectively.
Bahman Paygozar, R. Gorguluarslan· Fatigue & Fracture of En...· 0 citations
This study investigates the manufacturing process, progressive damage behavior, and multiobjective structural optimization of 3D angle‐interlock woven composites (3DAWCs) fabricated via the resin transfer molding process. The 3DAWCs consist of T700‐12K carbon fiber preforms and an epoxy matrix system (LT‐5028A/B). A representative volume element model is constructed from metallographic measurements. An enhanced Linde‐based progressive damage model incorporating shear coupling was implemented through the user‐defined material subroutine to capture the damage evolution of complex woven architectures. The numerical model is validated against uniaxial tensile tests in both warp and weft directions. And this model is employed to investigate the effects of the viscosity regularization coefficient and porosity on the mechanical response. Furthermore, an orthogonal experimental design combined with Pareto effect analysis and response surface methodology is employed to evaluate the effects of yarn spacing, width, and height on the warp‐ and weft‐direction peak stress and Young's modulus. The results indicate that weft height is the dominant parameter affecting the tensile strength, whereas warp width has a significant influence on stiffness. The optimized configurations achieve a balance between strength and stiffness in different loading directions, demonstrating the potential of mesostructural design for improving the mechanical performance of 3DAWCs.
This study presents a three‐dimensional cohesive phase field framework for simulating quasi‐static fracture in Gyroid lattice structures. To the authors' knowledge, this is one of the first experimentally validated applications of a diffuse cohesive phase field model to describe damage and fracture evolution in additively manufactured polylactic acid (PLA) lattice specimens. Due to the softening‐like mechanical behaviour exhibited by the 3D‐printed PLA specimens, the present work employs a high‐order cohesive generalised phase field model capable of capturing material softening once the maximum load‐carrying capacity is reached and energy dissipation becomes dominant. This modelling choice is essential to reproduce the gradual post‐peak degradation observed experimentally, which would not be adequately described by a purely brittle AT1/AT2‐type formulation. After validation in a two‐dimensional case, the approach is extended to the analysis of 3D‐printed Gyroid specimens subjected to tensile and compressive loading. Different Gyroid configurations, including unit cells and 2×2×2$$ 2\times 2\times 2 $$ clusters, were tested under tensile and compressive loading regimes using an in situ tensile/compression testing stage, with deformations and failure modes directly monitored through in situ imaging. Each experiment was recorded from multiple angles during tensile and compressive loading of the additively manufactured Gyroid specimens and compared frame by frame with simulation outputs, revealing good agreement in the prediction of crack initiation and propagation paths. The comparison between experimental and numerical results confirms the model's ability to capture the main tensile failure mechanisms and the softening‐driven fracture evolution in architected PLA lattices, while the compressive response is interpreted with caution in the late post‐peak regime due to mechanisms such as buckling, contact and densification. This versatile modelling framework lays the foundation for future studies incorporating additional physical phenomena—such as surface coatings, residual stresses, or micron‐scale effects—and for extension to other triply periodic minimal surface (TPMS) topologies beyond the Gyroid.
Deison Préve, J. Zenzerović, Emanuele Avoledo et al.· International Journal for Nu...· 0 citations
The integration of service holes in glulam beams is increasingly common in mass timber construction; however, these openings introduce stress concentrations that can compromise structural integrity through crack initiation and propagation. This study presents a robust numerical framework for simulating crack behavior around holes in glulam beams using the finite element software Abaqus. The framework incorporates the
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constitutive model, developed based on continuum damage mechanics, to capture the anisotropic damage evolution of timber under tensile and shear loading. Key modeling components include detailed geometric representation, layer-refined meshing strategies, and cylindrical orthotropic material systems to simulate the structure of the laminations. To validate the proposed approach, six glulam beams with three configurations—without holes, with a single hole, and with two holes—were tested under a single point load at midspan. The developed finite element models were calibrated and validated using experimental data, demonstrating strong agreement in terms of load–displacement responses and observed failure modes. The results confirm the model’s capability to predict the structural resistance and deformation behavior of perforated glulam beams. This predictive tool contributes to the advancement of structural design methodologies for engineered timber structures.
Zhiyong Chen, C. Dagenais· Journal of Structural Engine...· 0 citations