철근콘크리트 쉴구조물의 극한거동에 대한 인장강성 효과 = Tension Stiffening Effects on the Ultimate Behavior of RC Shells

다국어 초록 (Multilingual Abstract)

After cracking, concrete tensile stresses drop to zero rapidly at the side of crack and the direction that normal to the crack. But the tensile stresses are transferred from the reinforcement to concrete through bond-slip between the reinforcement and the surrounding concrete. The concrete ability which still carries a part of the applied load, after cracking, is known as tension stiffening. Lin’s model and Izumo's model are used in this study for tension stiffening and implemented in a computer program developed by Min and Gupta. We choose a hyperbolic saddle shell problem originally used by Lin and Scordelis for comparing the performance of various tension stiffening models. The result of Lin’s model showed that the ultimate load and tip displacement are increasing as the tension stiffening parameter increase. The load-deflection curve with Izumo’s tension stiffening model showed the behavior of the curve and the calculated ultimate strength is quite close with r =15 case of Lin's model. In comparing this study's result with Mahmoud-Gupta’s result, it is showed that the results of ultimate load and tip displacement of Mahmoud-Gupta's program is about 8 ~ 18% higher than the result of present study. Mahmoud-Gupta considered the tension stiffening effect with unrealistic behavior as we recognized. It is considered that we need to study and analyze many more RC shell structures to develope appropriate tension stiffening model.