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Structures designed to resist moderate and frequently occurring earthquakes must have sufficient stiffness and strength to control deflection and prevent any collapse. Since stiffness and ductility are generally two opposing properties; it is desirable to devise a structural system that combines these properties in the most effective manner without an excessive increase in the cost. Steel structural systems including moment resisting and concentrically braced frames have been widely used to resist earthquake loads. Concentrically Braced Frames (CBFs) have high stiffness, and due to the probable buckling of their diagonal members, are not ductile enough. Versus, Moment-Resisting Frames (MRFs) have adequate ductility as their beam sections can undergo inelastic deformations. However, due to the low stiffness of moment frames, the construction costs will be increased. In recent decades, steel shear panels are utilized as one of the lateral resistant systems, in Steel Plate Shear Walls (SPSWs), and the link beam of steel frames with eccentric bracing to achieve the aim of shear performance and keep the adjacent members in the elastic range. The Tubular frame is one of the common lateral resistant systems in which the columns are placed in close spaces and connected through deep MRF beams around the building perimeters. Based on the new design codes, the minimum limit of span-to-depth ratio (7 for moderate moment-resisting frames and 5 for special moment-resisting frames) is not satisfied at tubular system. So the idea of Shear Resisting Frames (SRFs) with non-prismatic beams connected by a shear fuse in the middle of the span was proposed as one of the alternatives. Using SRFs remove these limitations and increase the energy dissipation capability. In this new concept, the shear force in the beam is considered as the displacement-controlled component of the system. Similar to eccentrically braced frames (EBFs), the link is tuned as a sacrificial component so that the seismic energy is dissipated by shear yielding in a small segment in the middle of the beam. According to the stiffeners layout, lateral loading capacity in SRFs usually is achieved through buckling strengths or post- buckling capacity resulted from tension field action or load carrying capacity from the yielding of the web plates. So stiffeners play a crucial role in the lateral loading capacity of shear resisting frames and have a significant effect on the energy dissipation capability. Following this issue, the effect of transverse stiffeners with different layouts and placements (various spaces and two or one-sided arrangement) on the seismic performance parameters (response modification factor, overstrength factor and rotation capacity of link beam) of steel shear frames with different link length ratios where all of them are controlled with shear behavior, are evaluated by finite element cyclic and pushover analysis. At the end, an optimum space is proposed for different link length ratios and the response modification factors and overstrength factor of multi-story shear resisting frames including 3, 5, 7, 9, 10, 15, and 20-story for a specific link length ratio are presented. Also for facilitating the modeling process of multi-story SRFs in SAP2000 software, modeling parameters and acceptance criteria were extracted from cyclic and monotonic curves. Finally, pushover curves from SAP2000 were compared to ABAQUS to validate these parameters. At the end, a 25-story building with two different lateral resisting systems including tubular frame and SRFs were compared.

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Nowadays, building structures encounter with challenges such as construction speed and cost, especially in high seismicity zones. To accomplish this, steel structures was developed to accelerate the construction process and other economic issues. According to high strength ductility and energy dissipation, steel structure systems have been used widely in active seismic regions. The idea of application of shear panels has been using from many years ago as systems with high energy dissipation capability in EBFs as link beams and steel shear walls. The purpose of the EBFs design is the yielding of link beam and remaining the adjacent member at elastic region. According to the available criteria in design codes, shear in beams is a force-controlled action that exceeding the specified value as nominal strength is not permissible and the capacity design theory should be considered. Increasing the web thickness is the main effective factor achieving the needed shear strength and leads to the enhancement of plastic flexural capacity. The result of this action is more seismic demands in other structural members to keep in desirable operational level. So the shear plastic hinges is introduced instead of flexural plastic hinges at both ends. At this case because of uniform shear yielding through the web, energy dissipation capability is much better than the flexural yielding which begins from the outer face of the beam located on flanges. The web panels of built-up sections restrained by top and bottom flanges and two-sided transverse stiffeners have the ability to carry further loading beyond the web buckling load. The small lateral web displacements produced by excessive loading are not substantial because of available components to supply more resistance. Using adequate stiff transverse to resist against the out-of-plane deformation resulted from post-buckling; tension field actions are developed in shear panels before reaching the maximum shear strength by forming a truss with tension diagonals and compression verticals fixed by stiffeners.
The concept of shear resisting frames with non-prismatic beams were presented with the scope of reduction in link beam rotation, elimination of architectural limitations, restrictions on the ratio of span free length to beam total depth and high energy  dissipation capacity. Shear yielding and out of plane deformations caused by tension action field mainly control the frame behavior and energy dissipation. The proposed system is made up two strong side columns connected to the link element with weaker section in the middle of the frame as shear fuse with non-prismatic beams. Tendency to use haunched beams makes it feasible to achieve any link length ratio especially less than 1.0. This paper presents the introducing, design and performance of 1-story-shear resisting frames with different link length ratios (ranges from 0.5 to 1.6 with 0.1 variations) and shear-controlled behavior. The goal is achieved by implementing pushover and cyclic analyses numerically with ABAQUS software. But at first a verification analysis is done to validate the modeling procedure and reach a good conformity between numerical and experimental results. The outputs are presented in the form of response modification factor, displacement ductility and overstrength factor for pushover analyses and hysteresis behavior, backbone curve, energy dissipation capability and overstrength factor for cyclic analysis. Also at the end, 3, 5 and 7-story-frames were studied through pushover analysis and values of response modification factor and overstrength factor of the total frames presented. The results indicate desirable behavior of 1-story-shear resisting frames from the point of stiffness and strength degradation with high values of response modification factor equal to 9.18.