Effect of Using High-Strength Concrete and Ultra-High-Performance Concrete Material on Reinforced Concrete Beam with Opening under Flexural Load

Beams with opening are increasingly applied as alternative passages for services, such as electrical, plumbing, and telecoms. However, opening efficacy on the beam behavior under loading has been rarely explored. This study evaluates the effects of a square opening in the solid beam with different sectional sizes on the performance of reinforced concrete (RC) beams under flexural load. Two types of materials for the beam section are considered: high-strength concrete (HSC) and ultra-high-performance concrete (UHPC). The finite element model is developed to simulate simply supported RC beams subjected to flexural load. Four beams are modeled using HSC and UHPC with square openings in different sectional sizes, and nonlinear analysis is conducted by applying incremental load. Furthermore, a parametric investigation is resulted to evaluate the ability of various sizes of opening on the performance of beam under flexural load. Analysis results show that the created web openings in solid beam decrease the capacity of beam. However, solid small opening in beam can resist nearly the similar load of solid beam without any opening. Moreover, the load capacity of UHPC beams with opening is higher than that of HSC beams with opening.