The presence of part-through cracks with limited length is one of the prevalent defects in the plate structures. Due to the slight effect of this type of damages on the frequency response of the plates, conventional vibration-based damage assessment could be a challenging task. In this study for the first time, a recently developed state-space method which is based on the chaotic excitation is ...

In this study, a hybrid method is proposed to investigate the nonlinear vibrations of pre- and post-buckled rectangular plates for the first time. This is an answer to an existing need to develope a fast and precise numerical model which can handle the nonlinear vibrations of buckled plates under different boundary conditions and plate shapes. The method uses the differential quadrature element...

Direct Displacement-Based Design (DDBD) is a performence-based seismic design method that has been proposed and well developed over the past two decades to design RC frame structures, shear walls and bridges. In this method, the behavior of a multi-degree-of-freedom (MDOF) sysytem is approximaeted by an equivalent single-degree-of-freedom (SDOF) substitute structure. Although this method has be...

For this purpose a finite element model specifically developed for the nonlinear analysis of steel-concrete composite beams is adopted. This finite element model includes material nonlinearity of slab concrete, reinforcement steel, beam steel as well as slabbeam nonlinear partial interaction due to the deformable shear connection. The inclusion of the partial interaction in the composite beam m...

in the present study, the effect of core on shear lag phenomenon in tubular structures is investigated. three different tubular structure models including model without core, model with central core and model with central core but eliminated in last 15 stories have been analyzed. a shear lag index is defined for evaluating these models. from examination of the results, the effective influence o...

This paper presents a three-level supply chain model which includes single supplier, several distribution centers and sets of retailers. For this purpose, by adopting the queuing approach, a mixed nonlinear integer programming model is formulated. The proposed model follows minimizing the total cost of the system by determining: 1) the number and location of distribution centers between candida...