steel structures are usually built with some defects. according to the standard building codes, the central axes of the bracing members should go through the beam-column joints, however, in most of the braced steel structures, bracing members are unintentionally connected eccentrically. this paper presents a numerical investigation on performance analysis of cbfs (concentrically braced frames) ...

The main aim of this study, is to evaluate the seismic reliability of steel concentrically braced frame (SCBF) structures optimally designed in the context of performance-based design. The Monte Carlo simulation (MCS) method and neural network (NN) techniques were utilized to conduct the reliability analysis of the optimally designed SCBFs. Multi-layer perceptron (MLP) trained by back propagati...

Unpredicted loading caused by blast or impact may lead to severe damage in structures. Such damage may affect the whole structural performance. Connections are the key contributor to the integrity and energy dissipation capacity of the structural steel systems and play the most important role in mitigating such consequences. In the view of the importance of connections, finite element analysis ...

In this study, topology optimization is applied to concentrically braced frames in order to find economical solutions for conventional structural steel frames. Differential Evolution Algorithm and Dolphin Echolocation Optimization are applied for structural optimization. Numerical examples are studied and results of comparison with other meta-heuristic algorithms, including Genetic Algorithm, A...

The objective of this paper is to describe and analyze a series of nonlinear finite element analyses used to compare three design methods for locally slender, braced, steel beams and columns. The three design methods are: (i) the hot-rolled steel AISC Specification, (ii) the coldformed steel AISI Specification which uses the effective width method throughout, and (iii) the cold-formed steel Dir...

The experimental seismic testing of a 1/5-length scale model, slender bridge steel truss pier was conducted to investigate the use of a controlled rocking approach as a means of seismic protection. The controlled rocking approach allows the pier to uplift from its base, partially isolating the structure, while passive energy dissipation devices (steel yielding devices, fluid viscous dampers) ar...

A proper composition of stiffness and ductility parameters is required to obtain a resistant and economic structure. Accordingly, Chevron Knee Braced Frame (CKBF) seems appropriate due to its proper seismic performance. The advantage of this system comes to having the capability of rapid and cheap replacement of chevron knee elements after an earthquake occurs. In this research, response modifi...

zipper braced frames are an innovative bracing system for steel structures. conventional inverted-v-braced frames exhibit a design problem arising from the unbalanced vertical force generated by the lower story braces when one of them buckles. this adverse effect can be mitigated by adding zipper columns or vertical members connecting the intersection points of the braces above the first floor....

Fling-step and forward directivity are two important characteristics of near-field earthquakes. Forward directivity occurs when the rupture propagates toward the site and arises in fault‐normal direction for strike‐slip faults. Fling-step is the consequence of permanent ground displacement imposed by near-field earthquakes and arises in strike-slip faults in the strike parallel direction. Fling...