프리캐스트 콘크리트 계단 접합부의 접합방식에 따른 성능평가

Abstract

Dept. of Architectural Engineering, Seoul National University of Technology, Seoul 139-743, KoreaABSTRACT The time and cost can be reduced when applying partial precast concrete to the stair system in comparison to thecast-in-place or precast method. Because the performance of staircase which is used for evacuation can be largely different fromconnection types of precast concrete member, we tried to know structural behavior and performance evaluation according to eachtype of stair joints by experimental study. In the cast-in-place rigid joint, much reinforcement is needed in the end portion becausemuch stress is concentrated in the middle portion. Also, in the pin joint which is used in the connection point, the maximum stressoccurs in the middle point, so not only the amount of re-bar is increased but also the serviceability is largely decreased. The bolttype of semi-rigid joints proposed in this study had been increased strength and serviceability which is similar to the rigid joints.Also, its ductility was shown about 0.7 times in comparison to the rigid type and was about 2.8 times for the pin joint type. Accord-ing to the classification of joint in Eurocode, it can be considered that it is one of the semi-rigid joints which are in the semi-rigid-full strength, and the structural behavior can be expected by using a model which applied to stiffness value decreased by 40 percent.Keywords : partial precast concrete, stair joint, semi-rigid joint, effective stiffness