연구홍보포털

논문 초록 (Abstract)

The high strength materials have been more widely used in reinforced concrete structures because of the benefits of the mechanical and durable properties. Generally, it is known that the ductility dec reases with an increase in the strength of the materials. In the design of a reinforced concrete beam, both the flexural strength and ductili ty need to be considered. Especially, when a reinforced concrete structu re may be subjected an earthquake, the members need to have a sufficien t ductility. So, each design code has specified to provide a consi stent level of minimum flexural ductility in seismic design of concret e structures. Therefore, it is necessary to assess accurately the ductility of the beam sections with high strength materials in order to ensure the ductility requirement in design. In this study, the effects of concrete strength, yield strength of reinforcement steel an d amount of reinforcement including compression reinforcement on the co mplete moment-curvature behavior and the curvature ductility factor o f doubly reinforcement concrete beam sections have been evaluated and a newly prediction formula for curvature ductility factor of doubly RC beam sections has been developed considering the stress of compress ion reinforcement at ultimate state. Based on the numerical analys is results, the proposed predictions for the curvature ductility factor are verified by comparisons with other prediction formulas. T he proposed formula offers fairly accurate and consistent predic tions for curvature ductility factor of doubly reinforced concrete beam sections.