An Application of Strength Reduction Factors to Reinforced Concrete Columns considering Ductility

Title & Authors
An Application of Strength Reduction Factors to Reinforced Concrete Columns considering Ductility
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Abstract
Current design code states that the strength reduction factor shall be permitted to be increased linearly from that for axial compression to that for flexure as the design axial load strength $\small{\Phi}$cPn decrease from 0.1fckAg to zero. Since this empirically adopted axial load level of $\small{\Phi}$cPn=0.1fckAg considers only sectional area and concrete strength, the other variables such as steel ratio, steel yielding strength, and steel arrangement can not be considered. This research is performed to investigate the consistency and the rationality of the code requirement for determination of column design strength. A nonlinear axial force-moment-curvature analysis was conducted in order to investigate the ductility of reinforced concrete column sections. As the result of ductility analysis, it was found that the ductility at the axial force of $\small{\Phi}$cPn=0.1fckAg represented a lock of consistency for the various variable contained sections. Therefore, a more reasonable application method of strength reduction factor is proposed, that is based on the strain ductility index.
Keywords
reinforced concrete column;strain ductility index;axial force-moment-curvature relationship;strength reduction factor;
Language
Korean
Cited by
1.
철근콘크리트 휨부재 및 압축부재의 재료조항계수 적용에 관한 연구,김재홍;이재훈;

한국콘크리트학회논문집, 2000. vol.12. 2, pp.21-30
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