Non-linear flexural behaviour of RC columns including bar buckling and fatigue degradation

Abstract

An advanced fibre-based modelling technique is developed to characterise the nonlinear flexural behaviour of rectangular reinforced concrete (RC) columns by accounting for the influence of inelastic buckling and low-cycle fatigue degradation of vertical reinforcement. The proposed uniaxial material model of reinforcing steel is calibrated using 22 rectangular RC column tests. The influence of inelastic buckling of vertical reinforcement on the nonlinear cyclic response of rectangular RC columns is investigated. The calibrated model is capable of accurately predicting the nonlinear response of rectangular RC columns up to complete collapse by taking into account the additional failure modes of the RC columns.

Influence of advanced structural modeling technique, mainshock-aftershock sequences, and ground-motion types on seismic fragility of low-rise RC structures

“…The improved fiber beam-column model employed in this study significantly increases the capabilities of RC structural modeling by capturing the inelastic buckling and low-cycle fatigue degradation of longitudinal reinforcing bars. Previously, Kashani et al [28][29][30][31] developed a modeling technique for RC columns. In this paper, the same modeling technique is employed for RC building frames.…”

“…It has a parabolic curve up to the maximum concrete stress and a linear post-peak softening branch afterward. In another study [31] by the authors of this paper, it was found that After generating the FE model for the 2-story RC building, an eigenvalue analysis is performed after the gravity load analysis to compute the natural period of vibration of the structure, T1 (T1=0.5s). The computed T1 of the proposed model in this paper is slightly less than T1=0.6s reported by Haselton [24] using the lumped plasticity model.…”

The Behavior of Rectangular and Circular Reinforced Concrete Columns Under Biaxial Multiple Excitation

“…The numbers of fibers and the section discretization method are based on the recommendations provided by Berry and Eberhard [Berry and Eberhard] (2006). For more information regarding the methodology, formulation, calibration and validation of the model please refer to Kashani et al [Kashani, Salami, Goda et al (2017); Salami, Kashani and Goda (2019)]. Validated against experimental results, this computational modeling technique is capable to account for cyclic degradation of reinforcing bars due to inelastic buckling and low-cycle fatigue failure.…”

“…The model accounts for inelastic buckling and low-cycle fatigue degradation of longitudinal reinforcement and can simulate multiple failure modes of reinforced concrete structures under dynamic loading. A comprehensive detail of the model is available at Kashani et al [Kashani, Salami, Goda et al (2017); Dizaj, Madandoust and Kashani (2018); Salami, Kasani and Goda (2019)]. In addition to the advanced structural modeling, a comprehensive ground motion selection accounting for shallow crustal is implemented, as the hypothetical column is assumed to be located in Los Angeles, US.…”

A degrading Bouc–Wen model for the hysteresis of reinforced concrete structural elements

“…Repeated cyclic deformations frequently cause a deterioration of the characteristics of reinforced concrete (RC) mechanical systems. In fact, building structures may experience opening and closing of cracks, post-yielding and buckling of metallic elements (Kashani, Salami, Goda, & Alexander, 2018), strength and stiffness deterioration, and other local inelastic behaviours (Sivaselvan & Reinhorn, 2000). All these phenomena contribute to the structural damage.…”