In this research, the effect of different structural parameters on the dynamic behaviour of a thick plate with a smart attached mass, which is a mass embedded with the Shape Memory Alloy (SMA) fibers were investigated. The results showed that the inherent stiffness of the smart attached mass and the localized stiffness due to the effect of SMA fibers both play a significant role in the dynamic behaviour of the plate, and ignoring either of these parameters results in a considerable change in the system responses. The size and position of the smart attached mass were also found to be of particular importance, since the effect of the weight of SMA and attached mass and the forces induced by SMA transformation all have significant and sometimes conflicting effects on the system vibrations. The results also showed that the changes in the system parameters, and particularly the characteristics of the SMA fibers such as activation temperature, pre-strain, and volume fraction, result in the appearance of dynamic responses that cannot be neglected. Manuscript profile

A new systematic iterative analytical procedure is presented to predict the dynamic response of composite sandwich plates subjected to low-velocity impact phenomenon with/without initial in-plane forces. In this method, the interaction between indenter and sandwich panel is modeled with considering the exponential equation similar to the Hertzian contact law and using the principle of minimum potential energy and the energy-balance model. In accordance with the mentioned procedure and considering initial in-plane forces, the unknown coefficients of the exponential equation are obtained analytically. Accordingly, the traditional Hertzian contact law is modified for use in the composite sandwich panel with the flexible core under biaxial pre-stresses. The maximum contact force using the two-degrees-of-freedom (2DOF) spring-mass model is calculated through an iterative systematic analytical process. Using the present method, in addition to reducing the runtime, the problem-solving process is carried out with appropriate convergence. The numerical results of the analysis are compared with the published experimental and theoretical results. The effects of some important geometrical and physical parameters on contact force history are examined in details. Manuscript profile

The modal testing has proven to be an effective and non-destructive test method for estimation of the dynamic stiffness and damping constant. The aim of the present paper is to investigate the modal response of stiffened Fiber Metal Laminated (FML) circular cylindrical shells using experimental and numerical techniques. For this purpose, three types of FML-stiffened shells are fabricated by a specially-designed method and the burning examination is used to determine the mechanical properties of them. Then, modal tests are conducted to investigate the vibration and damping characteristics of the FML-stiffened shells. A 3D finite element model is built using ABAQUS software to predict the modal characteristics of the FML-stiffened circular cylindrical shells with free-free ends. Finally, the achievements from the numerical and experimental analyses are compared with each other and good agreement has been obtained. Modal analyses of the FML-stiffened circular cylindrical shells are investigated for the first time in this paper. Thus, the results obtained from this study are novel and can be used as a benchmark for further studies. Manuscript profile