Steel brace strengthening is the most popular seismic rehabilitation method for school buildings. This is because the design can be conducted by using relatively easy nonlinear pushover analysis and standard modeling in codes. An issue with steel brace strengthening is that the reinforced building should behave elastically to satisfy performance objectives. For this, the size of steel braces should be highly increased, which results in excessive strengthening cost by force concentration on existing members and foundations due to the considerable stiffness and strength of the steel braces. The main reason may be the brittle failure mode of columns, so this study investigated the relationship between the efficiency of steel brace strengthening and column failure modes. The result showed that the efficiency is highly dependent on the shear capacity ratio of columns and structural analysis methods. School buildings reinforced by steel braces do not need to behave elastically when the shear capacity ratio is low, and pushover analysis is used, which means reducing steel material is possible.

A B S T R A C T
1. 서 론
2. 철골 가새로 보강한 학교 건물의 특성
3. 대상 건물 선정 및 기둥 파괴모드 분석
    3.1 대상 건물
    3.2 기둥 파괴모드 분석
4. 학교 건물 모델링
5. 푸시오버해석을 통한 철골 가새 보강 효과 비교
6. 비선형동적해석을 통한 철골 가새 보강 효과 비교
7. 결 론
감사의 글
REFERENCES

• 이희섭(한울구조안전기술 사원) | Lee Hee Seop (Structural Engineer, Hanwool Structural Safety Technology)
• 김태완(강원대학교 건축토목환경공학부 교수) | Kim Taewan (Professor, Department of Architectural, Civil, and Environmental Engineering, Kangwon National University) Corresponding author