A major concern affecting the efficient use of carbon fibre reinforced composite laminates in the aerospace industry is the low velocity impact damage which may be introduced accidentally during manufacture, operation or maintenance of the composite structures. It is widely reported that the contact behavior of composite laminates under low-velocity impact can be obtained under quasi-static loa...

Hole drilling operations are common in fibre reinforced plastics FRP’s to facilitate fastener assembly to other parts in more complex structures. As these materials are non-homogeneous, drilling causes some damages, like delamination, for example. Delamination can be reduced by a careful selection of drilling parameters, drill material and drill bit geometry. In this work two types of laminates...

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...

This paper presents a multilayered/multidirector and shear-deformable finite-element formulation of shells for the analysis of composite laminates. The displacement field is assumed continuous across the finiteelement layers through the composite thickness. The rotation field is, however, layerwise continuous and is assumed discontinuous across these layers. This kinematic hypothesis results in...

Despite the benefits of composite structures, it is only recently that the main load bearing structures in large aircraft such as the Boeing 787 and Airbus A350 have started to be manufactured using carbon fibre composites. Even then, the unique directionality properties of composite laminates and design possibilities have yet to be exploited to improve the aircraft performance. In this study a...

The ballistic performance of the lightweight armour systems was examined to obtain an estimate for the V50 and the global damage of the composite plates. All estimates were performed by varying the thickness of ceramic tiles, while maintaining equal areal density of the system. Simulation predictions and trial results is demonstrated both in terms of deformation and damage of the laminates and ...

Gao, Zhenyuan MSAA, Purdue University, May 2015. Comprehensively Simulating the Mixed-Mode Progressive Delamination in Composite Laminates. Major Professor: Wenbin Yu. Delamination, or interlaminar debonding, is a commonly observed failure mechanism in composite laminates. It is of great significance to comprehensively simulate the mixed-mode progressive delamination in composite structures bec...

This paper presents an adaptive PSO algorithm whose numerical parameters can be updated following a scheduled protocol respecting some known criteria of convergence in order to enhance the chances to reach the global optimum of a hard combinatorial optimization problem, such those encountered in global optimization problems of composite laminates. Some examples concerning hard design problems a...

The efficient use of fiber reinforced polymer matrix composites in load-carrying structures requires detailed analyses to assess their mechanical performance, cost, and weight saving aspects. To accurately analyze the cyclic fatigue life of composite laminates, the influence of the physical non-linearity of the unidirectional lamina in the cyclic fatigue life analysis was examined using enhance...

A computational study is performed to determine the contribution to ultrasound attenuation in carbon fiber reinforced polymer composite laminates of linear elastic scattering by matrix micro-cracking. Multiple scattering approximations are benchmarked against exact computational approaches. Results support linear scattering as the source of observed increased attenuation in the presence of micr...