the base isolation systems are among the passive control devices that have been used over the last three decades to limit the seismic-induced response of structures. in this regard, the uniform building code provisions (ubc) has incorporated a special section for the seismic design of base isolated structures since its 1991 edition. due to the importance of the behavior of these structures unde...

In this paper, based on maximizing the outrigger-belt truss system’s strain energy, a methodology for determining the optimum location of an outrigger-belt truss system is presented. Tall building structures with combined systems of framed tube, shear core and outrigger-belt truss system’s are modeled using continuum approach. In this approach, the framed tube system is modeled as a cantilevere...

During recent years, the fabrics made from different yarns have been used for industrial purposes such as composite materials. Given the importance of the shear properties of these fabrics, a mechanical model based on the Grosberg and Park's Model for hybrid plain-woven fabrics is proposed. In this model, using the Energy method, the initial load-shear angle behavior of hybrid fabrics is calcul...

The Propose of this paper is to introduce a new model for crude oil fouling in preheat trains of crude distillation unit. The experimental results of Australian light crude oil with the tube side surface temperatures between 200-260 oC and fluid velocity ranged 0.25 to 0.4m/s were used. The activation energy of chemical reaction depends on the surface temperature has been calcula...

When polymeric liquids undergo large-amplitude shearing oscillations, the shear stress responds as a Fourier series, the higher harmonics of which are caused by fluid nonlinearity. Previous work on large-amplitude oscillatory shear flow has produced analytical solutions for the first few harmonics of a Fourier series for the shear stress response (none beyond the fifth) or for the normal stress...

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...