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Abstract: A novel three-phase shear lag model is derived to study the load transfer characteristics of the short fuzzy fiber reinforced composite (SFFRC) subjected to the thermomechanical loading. The distinctive feature of the SFFRC is that the short carbon fiber reinforcements coated with radially aligned carbon nanotubes (CNTs) are uniformly interlaced in the polymer matrix. The main novelty of the shear lag model derived in this study is that the interactions between the representative volume elements (RVEs) of the SFFRC, the application of the radial and the thermal loads on the RVE, and the radial as well as the axial deformations of different orthotropic constituent phases of the SFFRC have been taken into account. Particular emphasis has been placed on investigating the effect of waviness of CNTs on the load transfer characteristics of the SFFRC when the wavy CNTs are coplanar with either of the two mutually orthogonal planes. In the absence and the presence of the applied radial and thermal loads on the RVE, the shear lag analysis revealed that if the wavy CNTs are coplanar with the axial plane of the carbon fiber such that the amplitudes of the CNTs are parallel to the length of the carbon fiber then the load transfer characteristics of the SFFRC are significantly improved over those of the composite with and without the straight CNTs. The limiting value of the effective aspect ratio of the carbon fiber is also found for the efficient load transfer to the carbon fiber. [Copyright &y& Elsevier]

Abstract: The effective properties of a continuous fuzzy fiber-reinforced composite have been determined by employing the method of cells approach and the finite element (FE) method. The novel constructional feature of this fuzzy fiber-reinforced composite is that the uniformly aligned carbon nanotubes (CNTs) are radially grown on the surface of the horizontal carbon fibers. The effective properties of this fuzzy fiber-reinforced composite are estimated with and without the consideration of an interphase formed due to non-boned interaction between a CNT and the polymer matrix. Effective elastic properties of the fuzzy fiber-reinforced composite estimated by the method of cells approach have been compared with those predicted by the FE method. It has been found that the transverse effective properties of this composite are significantly improved due to the radial growing of CNTs on the surface of the carbon fiber. It is also found that the consideration of the CNT/matrix interphase has a negligible effect on the effective elastic properties of the fuzzy fiber-reinforced composite. [Copyright &y& Elsevier]

Abstract: This paper deals with the analysis of active control of vibration of thin laminated composite truncated circular conical shells using vertically and obliquely reinforced 1-3 piezoelectric composite (PZC) materials as the constraining layer of the active constrained layer damping (ACLD) treatment. A finite element model of smart truncated conical laminated shells integrated with the patches of such ACLD treatment has been developed to demonstrate the performance of these patches on enhancing the damping characteristics of thin symmetric and antisymmetric cross-ply and antisymmetric angle-ply laminated truncated conical shells. Velocity feedback control loop has been implemented to activate the patches. The effect of variation of semi-cone angle on the performance of the patches for controlling first few modes of the truncated conical laminated shells has been demonstrated. Emphasis has also been placed on exploring the effect of variation of piezoelectric fiber orientation angle in the constraining layer on the control authority of the ACLD patches. [Copyright &y& Elsevier]

In this paper, the performance of elliptical smart constrained layer damping treatments on active damping of geometrical nonlinear vibrations of smart laminated composite plates are analyzed. The constraining layers of the damping treatments are comprised of vertically/obliquely reinforced 1–3 piezoelectric composites, while the constrained layers are of isotropic viscoelastic material, modelled using the three dimensional fractional order derivative model. A meshfree model of the smart composite plate is developed for analyzing its nonlinear transient responses within the framework of a layerwise shear and normal deformation theory considering the von-Kármán type geometric nonlinearity. Thin composite plates integrated with elliptical/rectangular patches of the smart constrained layer damping treatments and having different stacking sequences and boundary conditions are considered for presenting the numerical results. The numerical analyses demonstrate the higher effectiveness of the elliptical patches over the rectangular ones in attenuating the nonlinear vibrations of laminated composite plates. [ABSTRACT FROM AUTHOR]

The present study addresses the static bending analysis of a dielectric nanobeam subjected to external electro-mechanical loads, considering the flexoelectric coupling, surface elasticity (SE) and surface residual stresses (SRS). In the current model, surface energies corresponding to the surface elastic strains and a traction jump across surfaces, based on the generalized Youngs-Laplace model, have been included. The numerical analysis is carried out by deriving the element free Galerkin (EFG) model for the dielectric beam based on a moving least squares (MLS) interpolation of the field variables. The effect of SE and SRS over the flexoelectric behaviour of the dielectric nanobeam are thoroughly examined here. The contrary effects of SE over the converse and direct flexoelectric behaviour is noted here. The effect of the SRS is observed to be dependent on the electrical field gradients. The present study reveals the significance of the SE and SRS for analysis involving flexoelectric behaviour in nano-sensors and actuators. • Significance of surface effects over exoelectric response is investigated. • Surface elasticity affects both direct and converse exoelectric behaviour. • Influence of surface residual stress depends on electromechanical boundary conditions. • Effect of surface residual stress depends on the deformed curvature. [ABSTRACT FROM AUTHOR]