Flexural performance of self-compacted perforated concrete beams under repeated loading

The current paper presents an experimental study in order to verify the flexural performance of a new developed perforated beam system. This system facilitates passing the pipes of utility services through its perforations as well as it has a good-looking appearance. Three main factors were studied; namely, the percentage of mass loss (14% 19% and 26%) due to the provided perforations, the reinforcement configurations around the perforations (orthogonal reinforcement, circular stirrups, and cross-bars) and the perforations shape (circular and oval). Therefore, three perforations sizes were studied having perforation diameter to the beam total depth ratio (D/t) of 0.38, 0.50, and 0.62. Accordingly, six perforated beams along with one solid reference beam were prepared and configured then tested under repeated loading till complete collapse. It could be concluded that the perforated beams of 200 mm perforations diameter (D/t = 0.5) reinforced by circular stirrups and cross-bars showed approximately the same flexural capacity as that of the solid beam but cross-bars stirrups enabled the perforated beam to develop approximately the same ductility as that of the solid beam. While, the beam with circular perforations (D/t = 0.5) provided by orthogonal reinforcement manifested increased flexural capacity by about 31% compared to that of the solid beam, while the developed ductility was lower than that of the solid beam by about 55%. In addition, the ductility could be outperformed by about 21% keeping the same ultimate capacity compared to those of solid beam provided that the mass loss of 14% was achieved as showed by the perforated beam with 150 mm perforations diameter (D/t = 0.38).