This research presents an experimental study to investigate the effect of coarse aggregate maximum size on the shear behavior of self-compacting concrete (SCC) and conventional concrete (CC) slender beams having the same compressive strength and make a comparison between the shear behavior of concrete beams. The experimental program included casting and testing eight beams with a constant size of 150mm height ×125mm width×1000mm length. Two coarse aggregate maximum sizes were used (10mm and 20mm) with SCC and CC in normal and high strength concrete. The results showed that increasing the coarse aggregate maximum size from 10mm to 20mm results in a slight increase in the diagonal cracking load and ultimate shear strength of SCC beams, while for CC beams the result was more significant. Also, it was found that the effect of increasing the coarse aggregate maximum size was more significant for normal strength as compared with high strength beams for both concrete types. Furthermore, the comparison between the shear behavior of SCC and CC beams having the same compressive strength and a concrete with the same coarse aggregate maximum size revealed that the SCC exhibited less diagonal cracking load and less ultimate strength compared with CC.

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This parametric study used finite element method (ETABS 2019), on 20 elliptical reinforced concrete cantilever deep beam specimens that have rectangular sections. Five parameters were taken into consideration: beam height, beam width, concrete compressive strength, load position and load type. Results showed that when the beam height was increased by 12%–66.5%, the negative and torsional moments and load capacity increased by about 11.23%–76.33%, 11.2%–77% and 11.1%–78%, respectively, whereas deflection decreased by about 15%–39%. The negative and torsional moments and load capacity increased by 26.13%–166.53%, 27%–172.5% and 28%–180%, respectively, and a decrease in deflection of about 1.73%–2.3% took place when beam width increased by about 14.3%–81%. In addition, increasing the compressive strength of concrete by 7.5%–36% led to an increase in the negative moments, torsional moments, load capacity, and deflection by about 8.22%–19.2%, 8.7%–20.4%, 9.4%–22% and 4.7%–7.1%, respectively. When changing the load type from concentrated to uniformly distributed over a third of the span’s length, two-thirds of the span’s length and then over the full span’s length, the negative moments increased by 5.23%, 8.47% and 52.67%, whereas torsional moments decreased by 1.1%, 1.12% and 16%, respectively. Finally, placing the concentrated load at a distance of 0.75, 0.5 and 0.25 of the span lengths led the negative moments to increase by 56.9%, 102.3% and 110%, respectively, whereas torsional moments decreased by 8.64%, 25%, and 58.3%, respectively. The load capacity increased by 87.5%, 243.75% and 556.25%, respectively, accompanied by a decrease in the deflection of the free end by 3.24%, 17.65% and 49.8%, respectively.

This research presents an experimental study to investigate the role of shear span-to-depth (a/d) ratio for the cross-sectional area of reinforced concrete beam on the deflection in reinforced concrete beams (deep and normal beams), when the value of shear span-to-depth ratio (a/d) equal to (1, 2, 3, and 4) respectively, the behavior of deep beams is significantly different from that of normal beams. Because of their proportions, deep beams are likely to have strength controlled by shear. The a/d ratio is to have a very significant role on the deflection where the values of a/d < 2 (deep beam) and the value of a/d > 2 (normal beam) according to (ACI 318-08) with the constant reinforcement ratio ρ The experimental program included casting and testing four beams with a constant width of cross section (b = 250 mm) and reinforcement ratio ρ. Also, all models of beams tested under two-point loads. The results showed that the percentage of average increasing in value of deflection in normal beam (a/d > 2) 1.68 % from value of deflection in deep beam (a/d < 2). Also, the gained deflection due to load in ranges from (10 to 110 kN) increase by (31.64 %) when a/d > 2 in TB1. moreover, the deflection due to load in ranges from (10 to 190 kN) increase by (21.28 %) when a/d < 2 in TB2. Furthermore, the gained deflection due to load in ranges from (10 to 360 kN) increase by (21.21 %) when a/d < 2 in TB3. as well as, in this research studied the role of shear span-to-effective depth ratio (a/d) on the crack width and the number of cracks.