DETERMINING MOMENT-CURVATURE RELATIONSHIP OF REINFORCED CONCRETE COLUMNS

Abstract

Determining the behavior of reinforced concrete (RC) members is crucial in RC structures. The nonlinear attributes of RC members are defined according to the cross sectional behavior of RC members to evaluate the performance of structures. To be able to determine cross sectional behavior of RC members, moment-curvature relationship should be known well.  In the RC structures, using moment-curvature (MC) relationship is the best way to represent cross sectional behavior and nonlinear properties of RC members. The MC relationship of RC cross sections can be evaluated by both experimentally or numerically. Some experimental studies on RC members which are applied with 1:1 scale can be difficult to define moment-curvature relationship. The purpose of the study is to obtain the MC relationship of RC rectangular and circular  and circular columns numerically. By the way this study is tried to achieve determining the parameters which affect MC relationship of RC members. In the study, to evaluate MC relationship of RC members XTRACT programme which represents influentially MC relationship is used. Compressive strength of concrete, axial load on the RC sections, longitudinal and transverse reinforcing ratio, are selected as comparison parameters which affect MC relationship. As a consequence of this study curvature ductility and effective flexural stiffness of RC rectangular and circular sections are determined using these parameters.  Effective flexural stiffness is compared with the values defined in design codes. As a result of comparison, it is observed that the moment curvature relationship can be defined as a formulation according to the parameters which affect directly. 

Keywords

• Moment-curvature relationship,Reinforced concrete columns

References

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