Peak and Cumulative Response of Reinforced Concrete Frames with Steel Damper Columns under Seismic Sequences

Abstract

The steel damper column is an energy-dissipating member that is suitable for reinforced concrete (RC) buildings and those used for multistory housing in particular. However, the effectiveness of steel damper columns may be affected by the behavior of surrounding members, and this effect can be severe in the case of seismic sequences. This article investigates the nonlinear response of building models with an RC moment-resisting frame (MRF) with and without steel damper columns under seismic sequences. The applicability of the concept of the momentary energy input to the prediction of the peak response of RC MRFs with damper columns under seismic sequences is also investigated. The main findings of the study are summarized as follows. (1) The peak response of RC MRFs with damper columns subjected to sequential accelerations is similar to the peak response obtained considering only the mainshock, whereas the cumulative strain energy of RC MRFs accumulates more for sequential accelerations. (2) The steel damper column is effective in reducing the peak and cumulative responses of RC MRFs in the case of sequential seismic input. (3) The relation of the hysteretic dissipated energy during a half cycle of the structural response and the peak displacement of the first modal response can be properly evaluated using the simple model proposed in this study.

Energy-Based Prediction of the Peak and Cumulative Response of a Reinforced Concrete Building with Steel Damper Columns

“…Eight-and 16-story building models are designed using the simplified procedure [5]. In the seismic design of these two frames, the displacement limit All MRFs are modeled as planar frames: the MRF with steel damper columns is modeled as in previous studies [5,7]. In this study, only half of the frame is modeled considering the symmetry of the structure.…”

“…Details of the modeling can be found in previous studies [5,7]. For simplicity, the stiffness degradation of RC members after yielding under cyclic loading, which was considered in a previous study [7], is not considered in this paper.…”

“…The calculation results for the 8-story model are shown in Figure 6(a), whereas those for the 16-story model are shown in Figure 6(b). In this study, displacement-based mode-adaptive pushover analysis [43] is applied to obtain the relationship between the equivalent acceleration (whole building: n D relationships are idealized as bilinear curves following a previous study [7].…”

Energy-Based Prediction of the Peak and Cumulative Response of a Reinforced Concrete Building with Steel Damper Columns

“…They are suitable for reinforced concrete (RC) housing because they minimize the obstacles in architectural planning. The authors have previously investigated the application of steel damper columns to RC building structures [3][4][5][6][7]. The nonlinear seismic response of existing moment-resisting frames (MRFs) retrofitted with steel damper columns was first investigated [3,4], and then a simplified displacement-based seismic design procedure for RC MRFs with steel damper columns was presented [5].…”

“…The influence of the strength balance between the steel damper columns and the surrounding beams in RC MRFs on the nonlinear response has also been investigated [6]. The nonlinear response of RC MRFs with steel damper columns designed according to the simplified design procedure described in [5] subject to seismic sequences was recently examined [7].…”