Shear Behavior of Fibrous Self Compacting Concrete Deep Beams

الملخص

Self-compacting concrete (SCC) is a relatively new generation of concrete that is characterized by the liquid nature that makes it appropriate for cast narrow members such as deep beams without vibration. The work aims to investigate the behavior of SCC deep beams and evaluate their shear capacity especially when steel fibers are used in their construction. The experimental work includes testing twelve reinforced concrete simply supported deep beams cast using self-compacting concrete (SCC) with steel fibers to evaluate their shear behavior and strength. All tested beams have dimensions of (100×330×1050) mm and have been subjected to two-point loads. The parameters considered are shear span to effective depth ratio (a/d), concrete compressive strength (fʹc), and steel fiber volumetric ratio (Vf). Test results indicated that the increase in (a/d) ratio from 0.6 to 1 leads to decreases in cracking and ultimate shear strengths by average ratios of 25.1 % and 20.6 % respectively. Increasing (fʹc) to twice the original value leads to increases in the cracking and ultimate shear strengths by average ratios of 13.9 % and 48.1 % respectively. Using steel fibers in SCC deep beams improves cracking and ultimate shear strength by average ratios of 33.1 % and 11.4 % respectively when 0.4 % of steel fibers are used while they improve these shear strengths by average ratios of 64.4 % and 23 % when 0.8 % of steel fibers are used...