INVESTIGATION OF THE MOMENT–CURVATURE RELATIONSHIP FOR REINFORCED CONCRETE SQUARE COLUMNS

Abstract

In this study; the effect of the material model, axial load, longitudinal reinforcement ratio, transverse reinforcement ratio and transverse reinforcement spacing on the behavior of reinforced concrete cross-sections were investigated. Squared cross-section column models have been designed. The effect of axial load, transverse reinforcement diameter and transverse reinforcement spacing on the behavior of reinforced concrete column models have been analytically investigated. The behavior of the columns was evaluated from the moment-curvature relation by taking the nonlinear behavior of the materials into account. The moment-curvature relationships for different axial load level, transverse reinforcement diameter and transverse reinforcement spacing of the reinforced concrete column cross-sections were obtained considering Mander confined model. Moment-curvature relationships were obtained by SAP2000 Software which takes the nonlinear behavior of materials into consideration. The examined effects of the parameters on the column behavior were evaluated in terms of ductility and the strength of the cross-section. In the designed cross-sections, the effect of transverse reinforcement diameter and transverse reinforcement variation on the confined concrete strength and the moment-curvature relationship was calculated and compared for constant longitudinal reinforcement ratio. The examined behavioral effects of the parameters were evaluated by comparing the curvature ductility and the cross-section strength. It has been found that transverse reinforcement diameters and transverse reinforcement spacing are effective parameters on the ductility capacities of the column sections. Axial load is a very important parameter affecting the ductility of the section. It has been observed that the cross-sectional ductility of the column sections increases with the decrease in axial load.

Keywords

• Transverse reinforcement
• Nonlinear
• Confined concrete strength
• Axial load
• Moment-curvature
• Curvature ductility

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