Reference EPFL-ARTICLE-184271doi:10.1016/j.compositesa.2012.08.001View record in Web of Science Record created on 2013-02-27, modified on 2017-05-10

Composites Part A: Applied Science and Manufacturing

The objective of this contribution is to present a unifying review on strain-driven computational homogenization at finite strains, thereby elaborating on computational aspects of the finite element method. The underlying assumption of computational homogenization is separation of length scales, and hence, computing the material response at the macroscopic scale from averaging the microscopic behavior. In doing so, the energetic equivalence between the two scales, the Hill–Mandel condition, is guaranteed via imposing proper boundary conditions such as linear displacement, periodic displacement and antiperiodic traction, and constant traction boundary conditions. Focus is given on the finite element implementation of these boundary conditions and their influence on the overall response of the material. Computational frameworks for all canonical boundary conditions are briefly formulated in order to demonstrate similarities and differences among the various boundary conditions. Furthermore, we detail on the computational aspects of the classical Reuss’ and Voigt’s bounds and their extensions to finite strains. A concise and clear formulation for computing the macroscopic tangent necessary for FE calculations is presented. The performances of the proposed schemes are illustrated via a series of twoand three-dimensional numerical examples. The numerical examples provide enough details to serve as benchmarks. [DOI: 10.1115/1.4034024]

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Aspects of Computational Homogenization at Finite Deformations: A Unifying Review From Reuss' to Voigt's Bound

A new method for generating random fibre distributions for fibre reinforced composites

Low-velocity impact response of composite sandwich structures: Modelling and experiment

This work investigates the effects of carbon/glass/basalt hybridization and fabric structure on the low velocity impact resistance of fibre reinforced plastic composites. Interply hybrid specimens used in the study were fabricated in a sandwich-like stacking sequence using a vacuum assisted resin infusion molding technique. Low velocity impact tests were carried out to study the effects of hybridization and fabric structure on the impact resistance of composite laminates. A continuum damage mechanical model was developed and validated for non-hybrid woven fabric laminates at different impact energy levels. Residual damage characteristics were identified using a 3D surface scanning system and an X-ray computed tomography (CT) method. On the basis of the experimental results, numerical simulation was also conducted to explore the damage mechanisms of the hybrid laminates. The study showed that: (a) hybrid laminates with carbon fibre as the core exhibited superior impact resistance for sandwich-like stacking sequence; (b) similar impact behaviors appeared for carbon laminates hybridised with either basalt or glass fibre; (c) for basalt fibre, weave fabric composite laminates exhibited better energy absorption capability and deformation resistance than cross-ply laminates reinforced in unidirectional fabrics.

/pdf/low-velocity-impact-behavior-of-interlayer-hybrid-composite-1ay521zk2m.pdf

Low velocity impact behavior of interlayer hybrid composite laminates with carbon/glass/basalt fibres

Study on the low-velocity impact response and CAI behavior of foam-filled sandwich panels with hybrid facesheet

Experimental and numerical investigation of interply hybrid composites based on woven fabrics and PCBT resin subjected to low-velocity impact

Effects of interphase properties in unidirectional fiber reinforced composite materials

Automatic generation of random distribution of fibers in long-fiber-reinforced composites and mesomechanical simulation

Water absorption and aging behaviors of fiber reinforced polymerized poly (cyclic butylene terephthalate) (GF/pCBT) composites are investigated. We coated nano-silica on glass fiber surface by physical vapor deposition (PVD) method. Subsequently, we immersed pCBT composites reinforced with nano-treated/untreated fibers in 25 °C and 60 °C distilled water until their saturated moisture. We also exposed some specimens in various hydrothermal aging environments. We tested the mechanical performance of these test specimens and found that the mechanical performance of both pCBT cast and GF/pCBT composites reduces obviously after water absorption and hydrothermal aging. However, nano-silica modified fiber reinforced composites have higher remaining strength than GF/pCBT. Scanning electron microscope (SEM) is used to study the microscopic phase and nanoparticle modified mechanism, and better interface characteristic between fibers and matrix is observed.

Jifeng Zhang

Papers

Study on the low-velocity impact response and CAI behavior of foam-filled sandwich panels with hybrid facesheet

Experimental and numerical investigation of interply hybrid composites based on woven fabrics and PCBT resin subjected to low-velocity impact

Effects of interphase properties in unidirectional fiber reinforced composite materials

Automatic generation of random distribution of fibers in long-fiber-reinforced composites and mesomechanical simulation

Effect of fiber surface modification on water absorption and hydrothermal aging behaviors of GF/pCBT composites