The seismic performance of elliptic braced moment resisting frame (ELBRF) is assessed here and is found that the structural behavior is improved and is of free of architectural space. The demand for seismic performance of ELBRF is estimated through conventional pushover methods of 3, 5, 7, and 10-story ELBRF frames and they are compared with special moment resisting frames (SMRF) and X-Braced C...

Buckling-Restrained Braced Frame system(BRBFs) are a new type of steel seismic-load-resisting system that has found use in several countries because of its efficiency and its promise of seismic performance far superior to that of conventional braced frames. The system is addressed in the 2005 edition of the AISC Seismic Provisions for Structural Steel Buildings, also a set of design provisions ...

When a steel moment-resisting frame deforms horizontally, H-shaped beams are subjected to the flexural moment gradient. Generally, rigidly connected box section columns possessing large fork restraint. Further, continuous braces on top flange effectively prevent lateral buckling. In this paper, buckling behavior of continuously braced with restraint under gradient is clarified theoretically and...

the objective of this paper is to determine the drift demand hazard curves of steel moment-resisting frames with different number of stories in territory of tehran this is done through the combination of the results obtained from probabilistic seismic hazard analysis and the demand estimated through the best probabilistic seismic demand models. to select the best demand model, in this paper, a ...

This paper suggested a new connection protocol, adding cover-plate between shear links and column, which was used to enhance moment and shear carrying capacity of beam, relax the restriction and assure the sufficiency development of plastic deformation of the link, and dissipate more earthquake energy. Considering the scale ratio of 1:3, the experimental data was achieved by a specimen under cy...

A case study of retrofitting a 20-story pre-Northridge steel moment-frame building is presented. Twelve retrofit 4 schemes are developed with varying degrees of intervention. Three retrofitting techniques are considered: up5 grading the brittle beam-to-column moment resisting connections, and implementing either conventional or 6 buckling-restrained brace elements within the existing moment-fra...

Most seismic codes specify empirical formulas to estimate the fundamental vibration period of buildings. Evaluated first in this paper are the formulas specified in present US codes using the available data on the fundamental period of buildings “measured” from their motions recorded during eight California earthquakes, starting from the 1971 San Fernando earthquake and ending with the 1994 Nor...

This paper is an experimental study on the behavior of vertical shear link in the single and double configurations. There have been three specimens selected for examining the effects of different details .The first specimen was an I section with no stiffener, while the second specimen composed of I section with stiffeners designed according to AISC 2005. Third specimens were composed of two I s...