| Title |
Effect of Vertical Irregularity on Displacement Concentration in Building Seismic Design Based on Linear Analysis |
| Authors |
손정훈(Sohn, Jung-Hoon) ; 최인섭(Choi, Insub) ; 김준희(Kim, JunHee) |
| DOI |
https://doi.org/10.5659/JAIK.2020.36.6.193 |
| Keywords |
Vertical Irregularity; Stiffness Irregularity; Soft Story; Displacement Concentration Factor; Displacement Concentration Amplification Factor |
| Abstract |
Recently, earthquakes with a magnitude of 5.0 or more have occurred in Pohang and Gyeongju in Korea, and the demands for seismic
performance evaluation of buildings has been increasing. In particular, in the case of Pohang earthquake induced a significant damage to the
middle and low rise piloti buildings. The purpose of this paper is to investigate the effects of displacement concentration on the buildings
with the vertical irregularity subjected to horizontal shear forces. Displacement Concentration Factor (DCF) was defined as the displacement
ratio of the first story to the top story to quantitatively analyze the degree of displacement concentration between equivalent static analysis
and response spectrum analysis for the buildings with vertical irregularity. Displacement Concentration Amplification Factor (DCAF) was
defined as the DCF ratio of the response spectrum method to the equivalent static analysis to compare displacement concentration on soft
story. In this paper, DCAF according to the stiffness ratio of soft story and the number of story was analyzed through 2D model. Also
DCAF value of 2D model was verified by 3D prototype model of 4-story piloti structure. The DCAF value tended to increase as the
stiffness ratio decreased and the number of story increased. It was confirmed that the response spectrum method should be applied instead
equivalent static analysis when the DCAF value is 1.35 or more according to the criteria of KBC 2016 |