the cracked brazilian disc (cbd) specimen is widely used in order to determine mode-i/ii and mixed-mode fracture toughness of a rock medium. in this study, the stress intensity factor (sif) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (x-fem). this method is based upon the finite element method (fem). in this m...

Tile responses of artificial neural networks to experimental and model generated inputs are compared for detection of damage in twisted fan blades using electronic holography. Tile training set inputs, for this work, are experimentally generated cllaracteristic pattenls of tile vibrating blades. Tile outputs are damage flag indicators or second derivatives of tile sensitivity vector projected d...

The worldwide progress to date in experimental and computational studies on composite frame structures having rectangular concrete-filled steel tube (RCFT) beam-columns and steel girders and braces has revealed their exceptional seismic resistance. In this paper, a computational study to develop reliability-based performance-based seismic design guidelines of RCFT members is presented. A three-...

Error estimâtes for the mixed finite element solution of 4th order elliptic problems with variable coefficients, which, in the particular case of aniso-/ortho-/isotropic plate bending problems, gives a direct, simultaneous approximation to bending moment tensor field ^ = {ipij)i<ij<2 and displacement field u\ have been developed considering the combined effect of boundary approximation and nume...

Because of different behavior of reservoir water and dam material, the determination of hydrodynamic pressure during earthquake is very complicated. Thus, different formulations have been presented for modeling of the dam reservoir system under dynamic loading such as earthquake. These formulations can be categorized into two general groups, which are Lagrangian and Eulerian, each having advant...

in the present paper, the modal analysis on a full finite element model of an off-road vehicle. this vehicle was modeled in the catia software and then meshed in the hypermesh software. the free vibration analysis was conducted by the abaqus software. by applying an external displacement, the forced vibration analysis was also performed. as a result, natural frequencies and shape modes were ext...

this research develops thermo-elastic analysis of a functionally graded cylinder under thermo-mechanical loadings. heat conduction equation in cylindrical coordinate system is solved. thermal conductivity coefficient is graded along the radial direction. by considering a symmetric distribution of temperature, loading and boundary conditions, strain-displacement and stress-strain relations can b...

A robust optimal-order multigrid method for the pure traction problem in two-dimensional linear elasticity is studied. The finite element discretization is a variant of a mixed method proposed by Falk where the displacement is approximated by nonconforming piecewise linear functions and the "pressure" is approximated by piecewise constant functions on a coarser grid. Full multigrid convergence ...