| Title |
Seismic Performance Evaluation of Full-Size R/C Frame Strengthened by CSTF Internal Connection Method |
| Authors |
강병훈(Kang, Byung-Hun) ; 정재원(Jeong, Jae-Won) ; 김의용(Kim, Eui-Yong) ; 이강석(Lee, Kamg-Seok) |
| DOI |
https://doi.org/10.5659/JAIK.2021.37.11.291 |
| Keywords |
Reinforced concrete; Seismic Capacity; Seismic Strengthening; Strength Increasing; Concrete-filled Steel Tube; Internal Connection; Pseudo-dynamic Test |
| Abstract |
This study proposes a seismic retrofitting method using a concrete-filled steel tube frame (CSTF) system, a novel technique to improve the
limitations of existing seismic strengthening methods. The CSTF method makes the most of the advantages of both concrete and steel pipes,
thereby significantly improving constructability and increasing integration between the existing structure and the reinfoR/Cement joints. This
method falls into the category of typical seismic retrofitting methods that focus on increasing strength, in which the required amount of
seismic reinfoR/Cement can be easily estimated. Therefore, the method provides an easy solution to improving the strength of existing
reinforcrd concrete (R/C) structures with non-seismic details that are prone to shear failure. In this study, a full-size two-story frames
modeled from existing R/C structures with non-seismic details was subjected to pseudo-dynamic testing. As a result, the effect of the CSTF
system, when applied to existing R/C structures, was examined and verified, especially as to its seismic retrofitting performance, i.e., restoring
force characteristics, stiffness reinforcement, and seismic response control. The results showed that the RC frame with no retrofitting measures
applied underwent shear failure at a seismic intensity of 200 cm/s2, the threshold applied in seismic design in Korea. In contrast, in the
frame retrofitted with the CSTF system, only minor earthquake damage was observed, and even when the maximum seismic intensity (300
cm/s2) that may occur in Korean was applied, small-scale damage was observed. These results confirmed the validity of the seismic
retrofitting method based on the CSFT system developed in the present study. |