This paper presents a practical methodology for optimization of concentrically braced steel frames subjected to forward directivity near-fault ground motions, based on the concept of uniform deformation theory. This is performed by gradually shifting inefficient material from strong parts of the structure to the weak areas until a state of uniform deformation is achieved. In this regard, to ove...

in this paper, the problem of layout optimization for x-bracing of steel frames is studied using the ant system (as). a new design method is employed to share the gravity and the lateral loads between the main frame and the bracings according to the requirements of the ibc2006 code. an algorithm is developed which is called optimum steel designer (osd). an optimization method based on an approx...

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) ...

This paper experimentally investigates the cyclic inelastic performance of concentrically braced frames with and without cold formed steel stud ~CFSS! infills designed to laterally restrain braces and delay their buckling. Specimens have either diagonal tube or solid bar braces with and without CFSS and U brackets providing out-of-plane and in-plane buckling restraint. Behavioral characteristic...

yielding elements (ye) are among those devices that not only help control structural damages, but make better seismic behavior by concentrating the frames in some removable part of the structures. ye are located at the intersection of concentric braced frame (cbf) in a rectangular shape. in this paper, seismic behavior of the frames with ye will be investigated. for this reason, 5 braced steel ...

Superelastic Shape Memory Alloy (SMA) is accepted when it used as connection in steel structures. The seismic behaviour of steel frames with SMA is being assessed in this study. Three eightstorey steel frames with different SMA systems are suggested, the first one of which is braced with diagonal bracing system, the second one is braced with nee bracing system while the last one is which the SM...

Both the Super-Elastic and Shape Memory Effect has been taken into account in this study by using SMA with high activation temperature. A Thermo-Mechanical SMA phenomenological constitutive model is used to simulate the SMA behaviour. The dynamic response data of a frame structure has been obtained from FE analysis by using the nonlinear FE software program MSC Marc. Then the frame is braced an...

The authors propose a design philosophy for steel buildings in moderate seismic regions that draws on familiar concepts of ductility and capacity design, but also integrates the concepts of reserve capacity, elastic flexibility and strength to broaden the field of design possibilities. The paper discusses structural systems representing each of these concepts: Moderate-Ductility Concentrically-...