Shear Capacity of Reinforced Concrete Beams Using High-Strength Concrete
Ashraf H. Elzanaty, Arthur H. Nilson, and Floyd O. Slate
Appears on pages(s):
(supports); compressive strength; cracking (fracturing);di-agonal tension; high-strength concretes; reinforced concrete; shear strength;span-depth ratio; web reinforcement.
Results of an experimental investigation of the shear strength of reinforced concrete beams made using concrete with compressive strength ranging from approximately 3000 to 12,000 psi (21 to 83 MPa) are summarized. A total of 18 beams was tested: 15 without web reinforcement and 3 with web reinforcement in the form of vertical stirrups. In addition to concrete strength, other variables included longitudinal steel ratio and shear span-to-depth ratio. Test results are compared with strengths predicted using the equations of ACI 318- 83. For beams without web steel, ACI Building Code equations may overestimate shear strength by 10 to 30 percent, particularly for higher concrete strength combined with normal to high shear-span ratios and relatively low longitudinal-steel ratios. For beams with web steel, all test strengths exceeded those predicted following present ACI code procedures.