Nonlinear modelling and finite element analysis on the load-bearing capacity of RC beams with considering the bond–slip effect

Abstract

Purpose This paper aims to present nonlinear numerical simulations using the versatile finite element (FE) analysis tool ANSYS and theoretical analysis based on code provisions to assess the load-carrying capacity of reinforced concrete (RC) beams under two-point monotonic static loadings. Design/methodology/approach Four quarter-size FE models with load and geometry symmetry conditions were constructed, the load-bearing capacity and associated mid-span deflections at critical points are verified against the full-scale experimental RC beams available in the literature. These developed FE models incorporated the tension stiffening effects and bond–slip behaviour. Theoretical analyses based on Indian standard code IS: 456–2000 and ACI 318–19 were also carried to verify the experimental and numerical predicted moments at critical loading points. Findings The load-deflection curves predicted through FE models exhibit closer corroboration with the experimental curves throughout the loading history. The contour plots for deflections, concrete principal stresses, reinforcement yield stresses are satisfactorily predicted by the FE models, which reveal the complete information of nonlinear behaviour of RC beams. The developed model well captured the initial and progressive crack patterns at each load increments. Practical implications The FE modelling is an efficient, valid and economical tool that is an alternative to the expensive experimental program and can be used to explore, analyse and fully understand the nonlinear response of RC beams under static loadings. Originality/value The ultimate moment capacity evaluated based on ACI 318–19 code provision show a better correlation with the experimental data as compared to the IS: 456–2000 code provision. The ultimate loads and associated centre-span deflections predicted by RN-2, RN-3, RB-12 and RB-16 FE model show a discrepancy of 1.66 and –0.49%, –4.68 and –0.60%, –9.38 and –14.53% and –4.37 and 4.21%, respectively, against the experimental results, which reveals that the developed ANSYS FE models predict consistent results and achieved a reasonable agreement with the experimental data.

Computational modeling and simulations for predicting the nonlinear responses of reinforced concrete beams

“…In this study, E s is defined by using the expression 4700 fc′. A Poisson ratio of 0.2 is assigned for concrete (ACI-318, 2019; Pandimani et al. , 2021a, b).…”

“…Besides, the yield stress and tangent modulus are input to the LINK180 element to model the bilinear elastic-plastic behavior of steel reinforcements (Kaya and Anil, 2021; Sayed, 2019; Yousaf et al ., 2017). The SOLID65 and LINK180 elements are discretized into 25 × 25 × 25 mm discrete elements along the length, depth, and width directions to get reliable solutions, as shown in Figure 2 (Kaya and Anil, 2021; Pandimani et al. , 2021a, b).…”

“…This element can effectively predict concrete's cracking and crushing phenomenon in three mutually perpendicular directions. This element also comprises plasticity, large deflection, stress stiffening, creep and swelling properties (Wolanski, 2004; Yousaf et al ., 2017; Pandimani et al. , 2021a, b; Naser et al ., 2021; Abuodeh et al ., 2021; Hawileh et al ., 2013).…”