Influences of non-uniform initial stresses on vibration of small-scale sheets reinforced by shape memory alloy nanofibers

Abstract

Abstract.In the present paper, an attempt is made to investigate the influences of biaxial preload on the vibrational behavior of small-scale composite sheets reinforced by shape memory alloy nanofibers. Three small-scale reinforced sheets are employed to form the system. In order to cover more practical cases, the biaxial preload and the compression ratio are assumed to be non-uniform. In addition, the three-layered composite sheet is embedded in a matrix with elastic properties. The Brinson model, nonlocal elasticity and Pasternak foundation model are used to take into account shape memory alloy effects, the influences of being size-dependent and the effects of the elastic matrix on the vibrational behavior, respectively. Performing a work/energy balance via Hamilton s principle yields the differential equations of motions. Finally, the natural frequencies are calculated via Galerkin s procedure. It is found that the natural frequencies of reinforced sheets under a preload of quadratic variation are higher than those of uniform and linear variations.