• 저자: 엄태성, 이승재, 조광원, 김민재, 이승환, 황현종
• Abstract : In large industrial buildings, precast prestressed concrete beams and composite columns are appealing to achieve longer span and higher story height, with temporary supporting and scaffolding minimized. To facilitate field erection of moment connection between precast beams and composite columns, a bracket connection transferring beam loads to the column by connecting the beam to a composite bracket attached to the column has been developed. Since precast beams are lap-spliced and integrated with the bracket by concrete engagement at the interfaces, the connection performance depends on beam lap length and load transfer details (i.e., concrete shear keys). In this study, the seismic performance of precast prestressed concrete beam-to-composite column joints with the bracket connection was experimentally and analytically investigated. Cyclic loading tests were conducted on four full-scale specimens with different beam lap lengths and load transfer details. For the specimens with a longer beam lap length, the bracket connection successfully transferred the beam flexural strength to the column with the connection barely damaged. The governing failure mode was beam flexural yield occurring at the bracket end. However, for the specimen with a shorter beam lap length, relative slips at the interfaces of the beam and bracket occurred and thus the strength was governed by the bracket connection. Excellent ductility satisfying the acceptance limit of special moment frame in AISC 341 was achieved in all specimens. The load transfer at the bracket connection through concrete shear keys and other details were further investigated through finite element analysis. Design models to predict the connection strength were proposed and the validity of the models was verified through comparisons with the tests and analyses.
• 요약 : PC보 단부에서 지압판, 확대머리 철근 등 보강 상세를 적용한 HMB 접합부 반복가력시험을 통해 HMB 접합부의 내진성능 확보를 확인함.

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• PC보-PSRC기둥 접합부 개발 및 구조성능 (선조립 앵글매입형 합성 기둥 및 브라켓)

• 저자: 이승환, 박호영, 강정호, 임종진

• 저자: 임종진, 엄태성, 황현종, 이승재, 이승환
• Abstract : Precast concrete (PC) and composite structures have been widely used in large industrial buildings for constructability and cost efficiency. The PC beams and composite columns are preferrable for use as long-span beams and large-sized columns, respectively, to realize efficient steel-concrete composite construction. The present study developed seismic details of the PC beam-to-composite column joint. A cyclic loading test was performed on the beam-column joints to investigate the seismic performance. For the test parameters, the connection details and the plastic hinge relocation were considered. The test results showed that the load-carrying capacity and deformation capacity of the specimens satisfied the requirements for intermediate moment frames specified in AISC 341-16. Further, the load-carrying capacities predicted using the plastic hinge relocation concept and the effective tension force of the bottom reinforcement at the PC beam section agreed with the test results.