in the aftermath of the 1994 northridge, california, earthquake. a significant number of steel moment resisting structural systems were damaged. many studies and researches have been conducted to improve the seismic performance of structures after the catastrophe. one of the proposed connections for special moment-resisting frames included aisc-358 is kaiser bolted bracket moment connection, br...

We revisit the significance of the increased number of great earthquakes since December 2004. An analysis of the global seismic moment release during 1918–2014 inferred from the International Seismological Centre catalog rejects a null hypothesis of independence between earthquake seismic moments and occurrence times. Our results suggest the existence of temporal variation in the seismic moment...

The present work is aimed at assessing the impact of strong column-weak beam (SCWB) criterion on seismic performance of optimally designed steel moment frames. To this end, different SCWB ratios are considered for steel special moment resisting frame (SMRF) structures and performance-based design optimization process is implemented with the aid of an efficient metaheuristic. The seismic collaps...

Today connections are playing an important role in the steel frames subjected to lateral seismic loading. The steel extended end-plate moment connection can play an important role in the steel frame when subjected to seismic loadings. In the past, this type of connection has been under investigation mainly when it was subjected to monotonic loading. After major recent earthquakes and failure of...

Dual systems of steel moment frame and reinforced concrete shear wall have combined the advantages of steel frames and reinforced concrete shear wall. These walls have increased the lateral stiffness of steel frames and have reduced seismic demands on steel frames thus providing opportunities to use such system. In this research intermediate dual system of steel moment frame was chosen with int...

The main aim of the present study is to optimize steel moment frames in the framework of performance-based design and to assess the seismic collapse capacity of the optimal structures. In the first phase of this study, four well-known metaheuristic algorithms are employed to achieve the optimization task. In the second phase, the seismic collapse safety of the obtained optimal designs is evalua...

Waveform inversion to determine the seismic moment tensor is a standard approach in determining the source mechanism of natural and man-made seismicity. The moment tensor is a general representation that includes the double-couple (DC) and non-double-couple sources such as explosions, opening and closing cracks, and volume compensated linear vector dipoles (CLVD). Previous studies (Ford et al.,...

We analyze the seismic moment-frequency relation in various depth ranges and for different seismic regions, using Flinn-Engdahl’s regionalization of global seismicity. Three earthquake lists of centroid-moment tensor data have been used: the Harvard catalog, the USGS catalog, and the HUANG et al. (1997) catalog of deep earthquakes. The results confirm the universality of the b-values and the ma...

In this paper, an optimization framework is developed for performance-based seismic design of composite moment frames consisting of concrete filled steel box columns and I-shaped steel beams. Material cost of the structure and seismic damage under severe earthquake ground motions are minimized as objective functions. Two design examples are presented to demonstrate the applicability and efficie...

Moment resisting frames as one of the conventional lateral load resisting systems in buildings suffer from some limitations including code limitations on minimum span-to-depth ratio to ensure the formation of plastic hinges with adequate length at beam ends. According to seismic codes, in ordinary steel moment resisting frames the minimum span-to-depth ratios should be limited to 5 and in speci...