Impact resistance and damage tolerance after impact are important performance reference indices in the structural design of composite stiffened panels. The evolution failure mechanism panels with foam-filled hat-stiffeners under low-velocity compression (CAI) at different positions energies were studied by experimental numerical simulation methods. delamination caused was captured ultrasonic ph...

Abstract This paper presents a novel approach to developing 2D structural theories for composite shells. The proposed uses the capabilities of Carrera Unified Formulation (CUF) in conjunction with Axiomatic/Asymptotic Method (AAM) obtain best given layouts. Different cases are considered analyze influence factors such as boundary conditions, lamination, and thickness on accuracy model. paramete...

The Bruggeman formalism is implemented to estimate the refractive index of an isotropic, dielectric, homogenized composite medium (HCM). Invoking the well–known Hashin– Shtrikman bounds, we demonstrate that the group velocity in certain HCMs can exceed the group velocities in their component materials. Such HCMs should therefore be considered as metamaterials. PACS numbers: 41.20.Jb, 42.25.Dd, ...

The influence of the outer reinforcement layers on repair structure and aerodynamic performance was studied. Firstly, a continuous damage mechanics model established, 3D Hashin criterion cohesive zone material were used to analyze model. failure load deviation 5.5%. Secondly, basis γ−Reθ transition SST–ω turbulence model, analysis DU300 airfoil established. numerical simulation results showed t...

This study presents a numerical analysis of failure in pultruded glass fibre reinforced polymer (GFRP) with three reinforcement layers, subjected to out-of-plane compressive loadings at low and high strain rates (10 -3 s -1 10 3 ). The simulations targets computationally efficient homogenization different element types sizes. A single-element model was created demonstrate the highest level homo...

This paper addresses the attainability of the Hashin-Shtrikman bounds for multiphase composites, including those of conductive materials and elastic materials. It presents a new derivation of these bounds that yield a necessary and sufficient condition for optimal microstructures. A key idea is a simple characterization of the gradient Young measures associated with optimal microstructures.

We present an alternative derivation of upper-bounds for the bulk modulus of both two-dimensional and three-dimensional cellular materials. For two-dimensional materials, we recover exactly the expression of the Hashin-Shtrikman (HS) upper-bound in the low-density limit, while for three-dimensional materials we even improve the HS bound. Furthermore, we establish necessary and sufficient condit...