STUDY of STRUCTURAL BEHAVIOR of BRACED STEEL of TALL BUILDING FRAMES

Abstract

In this study, it was applied the American Specifications for Structural Steel Buildings standard by taking the effect of the wind loads on designing of steel tall building frames depending on the location and topography of construction place. In order to study the structural behavior of the frames, different types of tall building forms were selected with typical plans and heights. These systems were rigid, shear-wall and tube frames. Each selected type of tall building frame was studied using three different types of bracing system, as well as, unbracing frame system. The bracing types were cross, diagonal and V-shape. The unbraced frames were assumed to be the basic reference for comparative purposes. The frames were defined, simulated, analyzed, and designed by analytical computer software (ETABS 2013). The analysis results were tabulated and presented according to maximum values of beam and column stresses and lateral story displacements. These analysis results were compared using graphical presentation. In order to get the frame with the minimum weight, the self-weight of braced frames were taken as percentage of unbraced frame weight. Then, the maximum story displacement of unbrace frames were obtained and compared by the same way. It was concluded that the weights of tube frame with diagonal bracing and V-shape bracing were reduced by 12.6% comparing with the unbraced tube frame. Also, the story displacement of rigid frame with cross bracing was reduced by 61% comparing with unbraced rigid frame.