In today’s market, it is imperative to be knowledgeable and have an edge over the competition. ACI members have it…they are engaged, informed, and stay up to date by taking advantage of benefits that ACI membership provides them.
Read more about membership
Become an ACI Member
Founded in 1904 and headquartered in Farmington Hills, Michigan, USA, the American Concrete Institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensus-based standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete.
American Concrete Institute
38800 Country Club Dr.
Farmington Hills, MI
Feedback via Email
Home > Publications > International Concrete Abstracts Portal
The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.
Title: Shear Capacity of Reinforced High-Strength Concrete Beams
Author(s): Shuaib H. Ahmad, A. R. Khaloo, and A. Poveda
Publication: Journal Proceedings
Appears on pages(s): 297-305
Keywords: beams (supports); cracking (fracturing); diagonal tension;reinforced concrete; shear strength; shear tests; span-depth ratio;structural design.
Abstract:Thirty-six reinforced concrete beams using high-strength concrete (uniaxial compressive strength, fc’ greater than 6000 psi [42 Mpa]) were tested to determine their diagonal cracking and ultimate shear capacities. All the beams were singly reinforced and were without shear (web) reinforcement. The concrete strength was not a prime variable and varied from 9,000 to 10,000 psi (63 to 70 MPa). The beams were tested for six shear span-to-depth a/d ratios and six percentages of longitudinal steel content p. Test results indicate that for slender beams of high-strength concrete and low amount of main reinforcement, the ratio of measured to predicted shear capacity of beams using the current A CI design Eq. (11-16) reduces to about 1.0. Furthermore, Eq. (11-16) of the ACI Building Code underestimates the effect of steel content p. For short beams (1 < a/d < 2.5) the code provisions are overly conservative. On the basis of experimental results of this and other studies, an empirical equation to estimate the ultimate shear capacity is proposed. The proposed equation for predicting the ultimate shear stress also includes the depth factor n to account for the observed decreased shear capacity with increased depth of the beam for a constant shear span-depth a/d ratio.
Click here to become an online Journal subscriber