In this paper, the transverse vibrations of rectangular plate with circular central hole have been investigated and the natural frequencies of the mentioned plate with point supported by Rayleigh-Ritz Method have been obtained. In this research, the effect of the hole is taken into account by subtracting the energies of the hole domain from the total energies of the whole plate. To determine th...

In this paper, an exact analytical solution for free vibration of rotating bi-layered cylindrical shell composed of two independent functionally graded layers was presented. The thicknesses of the shell layers were assumed to be equal and constant. The material properties of the constituents of bi-layered FGM cylindrical shell were graded in the thickness direction of the layers of the shell ac...

This study proposes damage detection algorithms for multistory shear structures that only need the first two or three natural frequencies. The methods are able to determine the location and severity of damage on the basis of damage location indices (DLI) and damage quantification indices (DQI) consisting of the changes in the first few squared natural frequencies of the undamaged and damaged st...

in this paper, natural frequencies of the sandwich plates with soft flexible core and composite face sheets are obtained. three-dimensional (3d) finite element method (fem) is used for constructing and analyzing of the sandwich plates to obtain their natural frequencies. continuity conditions for transverse shear stresses at the interfaces as well as transverse flexibility and transverse normal...

in this study, the vibration of cracked plates is investigated using the differential quadrature method and experimental modal analysis. the crack, which is assumed to be open, is modeled by the extended rotational spring. with its finite length, the crack divides the plate into six segments. then, the differential quadrature is applied to the governing differential equations of motion and the ...

A mesh-free method based on moving least squares approximation (MLS)  and weak form of governing equations including two dimensional equations of motion and Maxwell’s equation is used to analyze the free vibration of functionally graded piezoelectric material (FGPM) beams. Material properties in beam are determined using a power law distribution. Essential boundary conditions are imposed by the...

the present study utilizes an analytical method to formulate the three lowest modal frequencies of axially-loaded notched beam through both crack location and load level in a specific format that can be used in existing frequency-based crack-identification methods. the proposed formula provides a basis to shift into two states, one with axial loading and the other without any loading whatsoever...

the effect of a distributed patch mass on the natural frequency of vibration of a laminated rectangular plate with simply supported boundaries is investigated. the third order displacement field of a composite laminated rectangular plate is defined using the two variable refined plate theory. equations of motion of the plate are obtained with the help of calculus of variation. parametric study ...