when structures are subjected to strong ground motion excitations, structural elements may be prone to yielding, and consequently experience significant levels of inelastic behavior. the effects of inelastic behavior on the distribution of peak floor loads are not explicitly accounted for in current seismic code procedures. during recent years, many studies have been conducted to develop new de...

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....

The determination of structural and nonstructural damage under earthquake excitations is usually considered as a key factor in performance-based seismic design (PBSD) methods is In this regard, various damage indices have been developed in recent years to quantitatively estimate structural damage. The aim of this study is to develop a simple method to evaluate performance levels of zipper-brace...

When structures are subjected to strong ground motion excitations, structural elements may be prone to yielding, and consequently experience significant levels of inelastic behavior. The effects of inelastic behavior on the distribution of peak floor loads are not explicitly accounted for in current seismic code procedures. During recent years, many studies have been conducted to develop new de...

Different expressions have been developed to determine damping of structures based on various hysteretic models and ductility levels. Since Slenderness ratio is an important parameter on the hysteretic behavior of special concentrically- braced frames (SCBF), in this paper new expressions for determination of damping of such frames are developed based on slenderness ratio and ductility. Two typ...

This study is devoted to seismic collapse safety analysis of performance based optimally seismic designed steel chevron braced frame structures. An efficient meta-heuristic algorithm namely, center of mass optimization is utilized to achieve the seismic optimization process. The seismic collapse performance of the optimally designed steel chevron braced frames is assessed by performing incremen...

Near field earthquakes have imposed major damage to buildings in the past years. In some cases, the intensity of such damage is too considerable to be disregarded. The most effective way to improve seismic performance of buildings is applying a seismic control technique. The cylindrical friction damper is one of these methods, which has become popular for its desirable performance in the energy...

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...