Investigation of Effective Bending Rigidity Considering Different Code Approaches

Year 2020, Volume: 1 Issue: 1, 35 - 48, 19.06.2020

Gökhan Dok , Hakan Öztürk , Aydın Demir , Naci Çağlar

Abstract

In the study, the nonlinear behavior of reinforced concrete (RC) structures was investigated considering effect of effective bending rigidity under seismic loads. The cross-sectional effective bending rigidity (EIeff) of structural members was evaluated using different approaches of seismic design codes. The values of EIeff given in Eurocode-8, Turkish Seismic Design Code (TSDC) 2007 and Turkish Building Earthquake Code (TBEC) 2018, were used in a case study and compared with the initial (uncracked) section rigidity. The nonlinear single mode pushover analysis was carried out to determine the nonlinear performance of a RC frame structure model in SAP2000. In nonlinear pushover analysis, the lumped plasticity and plastic hinge theory were used to define nonlinear behavior of the structural members. The plastic characteristics of structural members were also evaluated using moment-curvature relationship in Xtract. The dimension of cross-sections and reinforcing details were chosen considering the design requirements of TSDC 2007 and TBEC 2018. The structural performance of the RC frame models with different stiffnesses was compared with performance of the model in which initial rigidity used. The base reaction force vs. top displacement demand, story drifts, and plastic hinge mechanisms obtained from the analyses were selected as comparison criteria. It was observed in the analysis results that a remarkable difference occurred in force and displacement demand between the models using the different effective bending stiffnesses.

Keywords

Effect of effective bending rigidity, nonlinear performance, reinforced concrete structure, pushover analysis

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