In the present research, the effects of delamination size and location on vibration characteristics of laminated composite beams are investigated both analytically and numerically. In the analytical method, the delaminated beam is modeled as four interconnected Euler–Bernoulli beams and the constrained and free mode models are both simulated. The differential stretching and the bending-extensio...

We propose a new 1–3 piezoelectric composite comprised of armchair single-walled carbon nanotubes imbedded in a piezoceramic matrix which we call a NRPEC (nanotube reinforced 1–3 piezoelectric composite). Values of effective piezoelectric and elastic moduli of the NRPEC determined through a micromechanical analysis are found to be significantly higher than those of the 1–3 piezoelectric composi...

The present paper investigates the advantages of a new class of composite grid structures over conventional grids. Thus far, a known grid structure such as orthogrid or isogrid has been used as an orthotropic layer with at most in-plane anisotropy. The present laminated grid is composed of various numbers of thin composite grid layers. The stiffness of the structure can be adjusted by choosing ...

Laminated composite plates are widely used in modern structures. Resins of composites are almost made of polymers which show time dependent and and in some cases stress dependent behaviour. In this paper, a laminated composite plate is analysed using a multiscale method. At first, material properties of a lamina is obtained using an analytical micromechanical approach called simplified unit cel...

In this paper, natural frequency and response of forced vibration of composite laminated conical shells under different boundary conditions are investigated. To this end, equations of Donnell's thin shell theory are used as governing equations. The analytical Galerkin method together with beam mode shapes as weighting functions is employed to solve the problem. Due to importance of boundary con...

in design and optimization process of laminated composite structures, the number of layers, layer angles, stacking sequence, material types and etc should be specified. each of aforesaid parameters can be applied as a design variable. in this paper the target is to minimize the weight of laminated composite pin loaded structures. the laminated composite structures are designed based on the load...

Global energy sources such as coal and oil are limited, and the burning of such fossil resources creates pollution problems. Wind energy offers one of several promising clean alternatives to carbon-based fuels. However, the composite materials currently available for producing wind turbine blades cannot accommodate the scale-up of wind energy due to their high price and disposal challenges (e.g...

A mechanical model for the prediction of mode I delamination failure of a laminated double cantilever beam (DCB) type specimen is presented. The volume of material ahead of the crack tip that experiences high stresses due to the presence of the crack tip was replaced by a nonlinear elastic spring foundation. The volume undergoing global deformation due to the external loading was replaced by a ...

In the treatment of orbital floor fractures, bone is ideally regenerated. The materials currently used for orbital floor reconstruction do not lead to the regeneration of bone. Our objective was to render polymeric materials based on poly(trimethylene carbonate) (PTMC) osteoinductive, and to evaluate their suitability for use in orbital floor reconstruction. For this purpose, osteoinductive bip...

This paper presents a solution to the boundary stabilization of a symmetric composite laminated plate in free transverse vibration. The symmetric composite laminated plate dynamics is presented by a linear fourth order partial differential equation (PDE). A linear control law is constructed to stabilize the plate. The control force consists of feedback of the velocity at the boundary of the pla...