This study is to investigate the effect of a retrofitted reinforced concrete frame with non-seismic details strengthened by embedded steel moment frames with an indirect joint, which mitigates the problems of the direct joint method. First, full-scale experiments were conducted to confirm the structural behavior of a 2-story reinforced concrete frame with non-seismic details and strengthened by a steel moment frame with an indirect joint. The reinforced concrete frame with non-seismic details showed a maximum strength of 185 kN at an overall drift ratio of 1.75%. The flexural-shear failure of columns was governed, and shear cracks were concentrated at the beam-column joints. The reinforced concrete frame strengthened by the embedded steel moment frames achieved a maximum strength of 701 kN at an overall drift ratio of 1.5% so that the maximum strength was about 3.8 times that of the specimen with non-seismic details. The failure pattern of the retrofitted specimen was the loss of bond strength between the concrete and the rebars of the columns caused by a prying action of the bottom indirect joint because of lateral force. Furthermore, methods are proposed for calculation of the specified strength of the reinforced concrete frame with non-seismic details and strengthened by the steel moment frame with the indirect joint.

A B S T R A C T
1. 서 론
2. 내부 매입형 철골조 내진보강공법 개요
3. 실험체 설계 및 실험 계획
    3.1 비내진상세 실험체 설계
    3.2 내부 매입형 철골 내진보강 실험체 설계
    3.3 재료특성
    3.4 가력 및 측정방법
4. 실험결과 분석 및 설계강도식 제안
    4.1 파괴양상
    4.2 하중-변위 관계
    4.3 설계강도식 제안
5. 결 론
REFERENCES

• 김선웅(영산대학교 스마트시티공학부) | Kim Seonwoong (School of Smart City Engineering, Youngsan University) Corresponding author
• 이경구(단국대학교 건축공학과) | Lee Kyungkoo (Department of Architectural Engineering, Dankook University)