The Development of Finite Element Model to Investigate the Structural Performance of Reinforced Concrete Hollow Beams

Abstract

The self-weight of a reinforced concrete beam contributes to the permanent loads of a structure. This can be reduced by creating a longitudinal void along the beam so that it will not affect the performance of the beam. In addition, this process can reduce the amount of building cost. Therefore, a finite element model was developed in this study with the aid of a computer program, Ansys, to investigate the behavior of the hollow beam. The model was tested for reliability by comparing the predicted results with those obtained from the experiment in terms of the load-displacement responses, mechanical properties, and parametric responses. The result showed that the reliability of the model was questionable. The main cause of the non-reliability was the inaccurate prediction of the beam deflection by the model. The poor prediction of beam deflection led to significant variations of relevant mechanical properties including stiffness, deflection, and ductility. For beam deflection, only 1/3 of the specimens were correctly predicted with a reliability of 36% while the strength properties were discovered to have higher values as observed in the yield and the ultimate strengths with 73% and 64% respectively. However, both the model and experimental results showed the hollow beam was relatively effective when the diameter of the longitudinal void was 1/3 times the beam width and placed at the neutral axis. For the evaluation to improve the reliability, some revision including the properties of the materials, boundary conditions of the beam support, bonding conditions between different materials, and meshing shape and size suppose to be applied to the model.

Dynamic Properties Comparison of 1D, 2D, and 3D Model for Concrete Box-Girder Bridge of 40-meter Span

“…At this stage, the large deformation occurred non-linearly, implying that non-linear analysis is required. This effect was also observed in recent studies by Effendi (2020) and Ling et al (2020). Moreover, the large displacements are unlikely to occur in prestressed girders since both deformation and stress in the concrete are practically limited by codes in order to avoid excessive deformation and crack.…”

“…However, this deduction was not applicable when the concrete structure acts as a cracksection such as reinforced concrete, since its tensile stress always exceeds the standard, thereby resulting in a change in cross-sectional rigidity during loading. This signifies that the noticeable error between numerical and experimental results tends to occur as found in Ling et al (2020) until the non-linear analysis was applied according to Effendi (2020).…”

“…Recently, Ling et al (2020) found that the numerical deflections of reinforced concrete hollow beams modeled as 3D solid are almost unreliable compared to experimental deflections. This inaccuracy was obtained because several issues were not considered in the modeling, such as meshing size in which no convergence test was performed, material properties, and steel-concrete bonding.…”

Non-Linear Finite Element Analysis of Flexural Reinforced Concrete Beam using Embedded Reinforcement Modeling

“…Smarzewski (2016) and Dahmani, Khennane and Kaci (2010) also studied the flexural failure of reinforced concrete beams using ANSYS while Özcan et al, (2009) used the same software to investigate the nonlinear behavior of steel fiber reinforced concrete beam until the ultimate failure cracks. Furthermore, Tjitradi, Eliatun, and Taufik (2017) analyzed the bending moment capacity, deformation, stress, strain, and fracture patterns of RC beams with different types of collapsed mechanisms using 3D ANSYS model and the software was also applied by Ling et al (2020) to study the effect of a hole in RC beam. Korol and Tejchman (2011) used ABAQUS to study the RC beam using an elastoplastic model with non-local softening for the concrete model while Słowik and Smarzewski (2012) applied nonlinear finite element analysis using ABAQUS to determine the shear failure of reinforced concrete beams without stirrups.…”

Structural Behaviour of Reinforced Concrete Beam with Embedded Polystyrene Spheres

“…Materials Reference Creating voids in beams PVC pipe [1,[3][4][5][6][7][8][9][10]] Plastic ball or void former [11][12][13][14][15] Plastic bottle [16][17][18] Seeding tray [19]…”