Passive Control Design Method for Mdof Slip-Hysteretic Structure Added With Visco-Elastic Damper

Abstract

Vicso-elastic dampers are increasingly used to reduce earthquake-induced vibration of building structures, including wood house structures which show slip hysteresis under earthquake loading. In this paper, simplified theories are proposed for seismic response evaluation and preliminary design of slip-hysteretic structures combined with visco-elastic dampers. They are based on the single-degree-of-freedom (SDOF) idealization of multistory structure, and produce the control performance curve expressing the peak responses as a function of stiffness of all components, based on spectral characteristics of the earthquake. Against the target peak response, a rule to convert the SDOF design to multistory design, with consideration to distribute damper stiffness over the height of structure, is also presented. Accuracy of the approach is demonstrated by time history simulations over a wide range of parameters.

A Displacement-Based Design Method for Seismic Retrofit of RC Buildings Using Dissipative Braces

“…That is one of the reasons why the design procedures based on the pushover analysis of the RC bare frame [29][30][31][32][33][34] may fail in this case study. On the other side, the optimal design procedures based on an equivalent shear-bar model [31,[42][43][44][45][46][47] neglect the torsional effects and, thus, their application to asymmetric in plan buildings deserves further study. Figure 22 shows the pushover curves of the damped braced structure and the performance points for the different limit states for two directions (X and Y) and two lateral force distributions (first mode and uniform).…”

“…As an alternative, Kasai et al [42][43][44] developed a method based on the SDOF idealization of the multistorey building structure and proposed a rule to arrange the damper stiffness over the height of the building so to produce the uniform distribution of drift angle and ductility demand under the design shear force, although those of the frame without dampers may be nonuniform. The damper design method giving optimal dampers distributions was initially proposed for elastic steel structures as well as elastoplastic structures including steel and timber structures [45] and then extended for retrofitting of existing RC structures with elastoplastic dampers [31,46]. This design approach is very useful since it gives a closed form expression for the required damper to RC frame stiffness and the optimal damper stiffness for each storey.…”

“…Finally, it should be highlighted that the design methods available in literature generally include only the first mode contribution while the contributions of higher modes in evaluating the response of MDOF elastoplastic system is neglected. Moreover, the design methods based on optimal dampers distributions [31,[42][43][44][45][46][47] are generally tested on twodimensional planar shear-bar models and their efficiency for 3D asymmetric building structures should be further investigated. Thus, they are fully reliable only when applied to symmetric-in-plan buildings and this is a very strong limitation since many existing RC buildings (including schools, hospital and other public buildings) are asymmetric in plan and/or in elevation.…”

“…Some authors [31,[42][43][44][45][46][47] have tried to overcome this limitation by developing damper design methods that give optimal dampers distributions, so that the distribution of ductility demand becomes uniform, although that of the frame without damper is nonuniform. However, these methods are generally based on a simplified shear beam model, while applications to 3D buildings models accounting for frame-damper interaction, higher modes effects, and plan irregularities are still lacking.…”

Evaluation of a Simplified Method to Estimate the Peak Inter-Story Drift Ratio of Steel Frames with Hysteretic Dampers

“…By using a displacement-based design method, a design procedure was investigated for buildings with hysteretic dampers [6][7][8]. To determine the optimal damper volume related to seismic performance, extant studies have used a performance curve (called as performance spectra) for an elastic system [9,10] and an inelastic system [2,[11][12][13] in the design process of buildings with dampers. However, these studies have not considered the turn from an elastic mode vector to an inelastic mode vector caused by the yielding of a main structure.…”