We investigate the feasibility of cohesive theories of fracture, in conjunction with the direct simulations of shear-load dominated fracture, to numerically reproduce the inter-sonic crack propagation in unidirectional graphite-epoxy composite plates [1]. The particular configuration contemplated in this study refers to the experiments performed by Coker and Rosakis [2, 3]. The numerical simula...

In the automotive and other industries, the visual appearance of external surfaces is a key factor in perceived product quality. Traditionally, the quality of automotive surface finish has been judged by expert human auditors. A set of 17 fibre-reinforced composite plates was previously manufactured to have a range of surface finish quality, and these plates were previously ranked by three expe...

In this paper, nonlinear equations of motion for laminated composite rectangular plates based on the first order shear deformation theory were derived. Using a perturbation method, the nonlinear equation of motion was solved and analytical relations were obtained for natural and nonlinear frequencies. After proving the validity of the obtained analytical relations, as an alternative and simple ...

This study investigates the applicability of time reversal concept in modern acoustics to structural health monitoring. A time reversal method has been adapted to guided-wave propagation to improve the detectability of local defects in composite plate structures. Specifically, wavelet-based signal processing techniques have been developed to enhance the time reversibility of Lamb wave in thin c...

Agave is the one of the abundantly available plant in India. The wide application of agave reinforced composite plate necessitate the joining of two plates together. For making such joint drilling of those plates is required. Drilling of natural fiber composites is different from the other metals because of its mechanical properties. The major problem faced in drilling of theses natural fiber c...

The Layerwise Shell Theory is used to model discretely stiffened laminated composite plates and cylindrical shells for stress, vibration, pre-buckling and post-buckling analyses. The layerwise theory reduces a 3-D problem to a 2-D problem by expanding the 3-D displacement field as a function of a surface-wise 2-D displacement field and a 1-D interpolation polynomial through the shell thickness....

Impact-induced damage in fiber-reinforced laminated composite plates is characterized. An instrumented impact tower was used to carry out low-velocity impacts on thirteen clamped glass/epoxy composite plates. A range of impact energies was experimentally investigated by progressively varying impactor masses (holding the impact height constant) and varying impact heights (holding the impactor ma...

This paper analyzes an electromagnetic model of radar-absorbing layered structures for several stacking sequences of a woven glass/vinyl ester laminate, foam layers, and resistive sheets. It considers configurations that are either deposited on different backing materials or embedded in a laminated sandwich plate. Through-the-thickness layer dimensions and sheet resistances offering the best si...

An active control strategy for controlling impact response in composite plates is proposed. A linear quadratic regulator (LQR) controller is designed based on a reduced-order model that captures the essential dynamics of the system. Simulations results show that the proposed controller reduces the energy transferred to the structure. Thus, the possibility of impact-induced structural damage is ...

This paper outlines an experimental investigation carried out for the analysis of failure mechanisms in fibrous laminated composite plates containing stress raisers, in the form of cutouts, under static biaxial planar compressive loadiing. A specially designed biaxial loadiing frame was used to test a series of 48 ply graphite/epoxy composite laminated plates with centrally located circular hol...