Numerical modeling of reinforced concrete structures made of lightweight concrete using ANSYS

In this paper, extensive numerical investigations into reinforced concrete beam made of lightweight concrete are given, through the ANSYS finite element program. The main aim was to assess the load carrying capacity, stiffness and deformation characteristics of the beams of different concrete densities. There were seven beam specimens, which vary in the percentage ratio of lightweight to normal aggregates, and the material properties were duly incorporated in the model. Three-dimensional nonlinear finite element analysis was used to simulate the beams with a mesh size of 25 mm, and the results were compared with the experimental results. Results showed that when the concrete density was reduced the loadbearing capacity decreased gradually, as the concrete became normal weight (95 kN) and then fully lightweight (85.7 kN). Nevertheless, the plastic zone transition happened later in lightweight beams and this implies that the deformation resistance was more difficult than in normal-weight concrete. The load-deflection curve demonstrated the fact that lightweight concrete beams though less stiff in nature, are structurally reliable and competitive. This study highlights the possibility of the lightweight concrete to be used as a structural material in contemporary engineering practice and therefore seismic zones where minimized self-weight improves the overall safety and efficiency. The results are useful in understanding how to optimize and design the reinforced lightweight concrete members.