Flexural Response Prediction of Reinforced Concrete Members Based on Statistical Observations

Abstract

Seismic assessment of reinforced concrete (RC) structures requires the determination of inelastic deformation capacity of structural members. Inelastic deformation capacity of members is determined by performing analytical moment-curvature analysis. Due to definition of high amount of data, this type of analysis increases the computational efforts and time when applied to large structures. Considering this situation, this paper proposes simple equations to express inelastic deformation capacity of rectangular RC sections subjected to axial load and uniaxial bending moment. Deformation of members is described in domains of strength and deformations at yield and ultimate. In order to increase applicability and coverage of equations, numerous RC sections were analyzed for various axial load levels by combination of different section aspect ratios, longitudinal and transverse reinforcement configurations and distinct structural materials. During the analysis, nonlinear characteristics of constitutive materials are modeled and some remarkable effects are considered: capacity of concrete in tension, yield elongation and hardening of the longitudinal reinforcement. Equations are then proposed by investigating the effect of sectional and material parameters on the moment-curvature responses and contribution of parameters assigned to prediction equations by extensive statistical evaluations. Reliability of proposed equations is eventually investigated and validated by numerical, experimental and analytical moment-curvature analysis results. It is expected that proposed equations, in close precision, can be helpful for rapid visualization of inelastic capacities of RC members.