Title |
Longitudinal Reinforcement Ratio for Performance-based Design of Reinforced Concrete Columns
|
Keywords |
철근콘크리트 기둥 ; 주철근비 ; 크리프 및 건조수축 ; 연성능력 ; 유효강성 reinforced concrete column ; longitudinal reinforcement ; creep and shrinkage ; ductility ; effective stiffness |
Abstract |
The longitudinal reinforcement ratio for the performance-based design of columns was studied. Unlike the existing design codes using uniform minimum reinforcement ratio and effective stiffness for all columns, the longitudinal reinforcement ratio of columns was defined as the function of various design parameters. To evaluate the minimum reinforcement ratio, two conditions were considered: 1) prevention of passive yielding of compression re-bars due to the creep and shrinkage of concrete under sustained service loads; and 2) ultimate flexural strength greater than the cracking moment capacity to maintain the ductility of columns for earthquake design. In addition, the effective flexural stiffness of columns for structural analysis was determined according to the longitudinal reinforcement ratio. The design method addressing the three criteria was proposed. The proposed method was applied to a design example.
|