Numerical study of the behavior of reinforced concrete beams with different characteristics subjected to impact loads

One of the challenges facing structural engineers is to identify the performance of important structures against heavy impact loads, therefore, the need to investigate this type of load on structures is increasingly felt. The main purpose of this study was to evaluate the effect of support conditions, span length, and strength of concrete and reinforcement percentage on the performance of reinforced concrete beams against the impact load of 50 kg spherical falls on a height of one meter. For this purpose, after validation, a number of reinforced concrete beams with the same cross section but with simple and rigid support conditions, span lengths of 3, 4 and 5 meter, strengths of 25, 30 and 35 MPa, as well as minimum, standard and maximally longitudinal reinforcement values, modeled and analyzed in Abaqus software. The results of this study show that for 3, 4 and 5 m lengths, the boundary conditions change from simple to rigid, reducing the mid beam displacement by 46.91%, 45.55% and 39.46%, respectively. By changing the characteristic strength of concrete from 25 to 35 MPa, the maximum displacement for rigid support and the simple support order of 10.17% and 10.9% reduced. By increasing the amount of reinforcement from minimum to maximum reinforcement, the maximum amount of force applied to the beam for the rigid and simple support reinforcement increased by 33 and 32.66 percent, respectively. The use of stirrups special led to an increase of 13 percent of the beam is tolerable.