Evaluation of Flexural Strength of Stirrup less Voided Beam of Conventional or Reactive Powder Concrete

Light-weight beam has received considerable critical attention to decrease the stresses or to increase spans. This study was undertaken using double spherical plastic bubbles in a specific zone (shear zone) to evaluate the flexural behavior of the stirrup less beam. Two types of concrete (conventional concrete of ordinary Portland cement and high strength concrete of reactive powder (RPC) reinforced by steel fiber) were used to obtain four beam specimens' of 1300 mm in length, two beams have double spherical plastic bubbles and two beams in solid form as a reference. These beams were prepared to investigate the effect of plastic bubbles, concrete strength, and steel fiber on the shear behavior under a flexural moment. Results indicated that the flexural strength of bubbled beams was decreased for the two types of concrete. In contrast, the specific flexural strength was much closed due to the concrete density reduction by (6.22 and 6.24)% for conventional and high strength concrete respectively.