The self-compacting concrete (SCC) was invented to overcome the compaction problems in deep sections, owing to its perfect workability characteristics. Steel fibers when used with SCC would affect the required fluidity characteristics but improve its impact resistance. In this research, an experimental work was conducted to evaluate the impact response of micro-steel fiber-reinforced SCC, under flexural impact. A 5.47 kg free-falling mass was dropped repeatedly from 100 mm height on the top center of 270 mm-length beam specimens. Eight mixtures with two design grades of 30 and 50 MPa were prepared to distinguish the normal and high-strength SCCs. The distinguishing variable for each design grade was the fiber content, where four volumetric contents of 0%, 0.5%, 0.75%, and 1.0% were used. The test results showed that the impact resistance and ductility were significantly improved due to the incorporation of micro-steel fibers. The percentage improvements were noticeably higher at failure stage than at cracking stage. For the 30 MPa mixtures, the maximum percentage improvements at cracking and failure stages were 543% and 836%, respectively. Weibull’s linear correlations with R2 values of 0.84 to 0.97 were obtained at the failure stage, which meant that the impact failure number followed the Wiebull distribution.

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      The test results of six reinforced concrete moderate deep beams with embedded PVC pipes are reported. The tests studied the effect of installation of PVC pipe on behavior of reinforced concrete moderate deep beams. The test parameters were the diameters and locations of the pipes. The dimensions of beams were 1000 mm length, 150 mm width and 300mm depth. One beam was constructed without pipe as control and the remaining five had embedded pipes. Four pipe diameters were used: 25.4, 50.8, 76.2, and 101.6 mm and these pipes were inserted longitudinally either at the center of the beams or near the tension reinforcement. The beams were simply supported and tested under central concentrated load up to failure. The test results indicated that, the pipe diameter less than 1/3 of the beam width had limited effect on the capacity and rigidity of beam. For larger pipes, the ultimate strength of beams decreased between 16.7% and 33.3% and the beams stiffness decreased between 103% and 297%.

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