Advanced carbon-fibre composite materials are increasingly used as primary structural components in aviation and aerospace industries due to their high stiffness-to-density ratio. The design of composite aerostructures is required to meet a number of safety criteria, in particular, the damage tolerance. Delaminations, which are caused by the impact of foreign objects (tool drops, runway debris,...

In this article, free vibration analysis of variable stiffness composite laminate (VSCL) plates with flat and folded shapes is studied. In order to consider the concept of variable stiffness, in each layer of these composite laminated plates, the curvilinear fibers are used instead of straight fibers. The analysis is based on a semi-analytical finite strip method which follows classical laminat...

Synopsis A theoretical study of viscoelastic properties of composites is presented with the aim of identifying structures which give rise to a combination of high stiffness and high loss tangent. Laminates with Voigt and Reuss structure, as well as composite materials attaining the Hashin-Shtrikman bounds on stiffness were evaluated via the correspondence principle. Similarly, viscoelastic prop...

0263-8223/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.compstruct.2009.01.006 * Corresponding author. Tel.: +1 514 690 4151; fax E-mail address: [email protected] (H. Designing an optimized composite laminate requires finding the minimum number of layers, and the best fiber orientation and thickness for each layer. To date, several optimization methods have been introduced ...

Influence of the stacking sequences of hybrid composites on the tensile strength, flexural strength, inter-laminar shear strength (ILSS) and impact energy was investigated. The hybrid glass-basalt-carbon/polyester composite laminates were processed by hand lay-up procedure at room temperature. The fracture surface of the composite laminates after the tension and flexural test was examined by sc...

In recent years, ultrasonic methods have been developed that can measure the mechanical stiffness of composites. The Lamb wave velocity is directly related to the material parameters, so an effective method exists to ascertain the stiffness of composites by measuring the velocity of these waves. In this study, a Lamb wave measurement system was used to measure the bending and out-of-plane stiff...

The present paper focuses on the development of a multiscale optimisation strategy for the optimisation of variable angle stiffness laminates. The main goal consists in proving that it is possible to design structures having complex shapes made of variable stiffness composites by taking into account, from the early stages of the design process, the constraints linked to the manufacturing process.

imperialist competitive algorithm (ica) is a new socio-politically motivated global search strategy. the ica is applied to hybrid composite laminates to obtain minimum weight and cost. the approach which is chosen for conducting the multi-objective optimization was the weighted sum method (wsm). the hybrid composite laminates are made of glass/epoxy and carbon/epoxy to combine the lightness and...