مقاله انگلیسی رایگان در مورد ارزیابی ایمنی احتمالاتی قاب فولادی – اسپرینگر 2017

Main building codes [1,2] ensure life-safety and collapse prevention of conventional buildings under design earthquake loads using ductility and strength capacity of members [3]. However, code-compliant buildings incur significant damage during a severe earthquake [4]. Nowadays, the new generation of lateral resisting systems such as rocking braced steel frames [5], rocking wall-frame structures [6,7], self-centering timber systems [8,9], confined masonry rocking walls [10], and post-tensioned steel moment resisting frames [11,12] have been developed to overcome technical flaws and socio-economic drawbacks of conventional buildings. Previous studies have shown that these low-damage systems can significantly reduce soft-story failure, drift concentration, and plastic deformation of structural elements by directing damages to replaceable energy dissipation devices such as steel yielding fuses [13,14], viscous dampers [15], and friction bearings [16]. Unlike conventional fixed-based system, the selfcentering system is isolated from gravity framing system, which makes it possible to rock upon the foundation during an earthquake. The pioneering efforts to examine the efficiency of self-centering systems are due to Clough and Huckelbridge [17] and Kelley and Tsztoo [18] studies, and, more recently, it has been confirmed for several types of self-centering systems [19–21]. There are several configurations for self-centering systems equipped with different fuse types and post-tensioning locations. A number of studies have focused on performance of the single [14–16] and dual configuration controlled-rocking frame equipped with PT strands and different energy dissipation devices. The post-tensioning strands are restrained uprightly to the top and bottom of the frames and yielding fuses are placed between two rocking frames. Post-tensioning strands provide restoring forces and prevent permanent displacement and replaceable fuses are to damp the seismic energy. A team from Lehigh University was the pioneering researchers to explore the self-centering chevron-braced frames (0.6-scale) equipped with friction-bearing dampers [22], which was tested using multi-dimensional hybrid simulations [23]. The simplified analytical method for estimating structural demands of this system were proposed by Roke et al. [16] and further analytical studies have been done by Sause et al. [24] and Chancellor et al. [25]. Working in collaboration with researchers at the University of Illinois, Ma et al. [14] tested the three-story single self-centering frame (0.68-scale) on the E-defense shaking table. As another alternative configuration of selfcentering systems, Wiebe and Christopoulos [27] tested the 8-story multiple rocking joints self-centering systems (0.3- scale) to mitigate the deficiency of higher mode effects and proposed a performance based design strategy [3]. The examples of self-centering systems were also implemented in practice [15,28].