Title: Shear Strength of Two-Span Continous Reinforced Concrete Beams

Author(s): Jose J. Rodriguez, Albert C. Bianchini, Ivan M. Viest, and Clyde E. Kesler

Publication: Journal Proceedings

Volume: 55

Issue: 4

Appears on pages(s): 1089-1130

Keywords: no keywords

Date: 4/1/1959

Abstract:
Fifty-two continuous reinforced concrete beams were tested under concentrated loads and the results analyzed in on effort to determine the following: (1) effect of continuity on the shear strength of statically indeterminate members, (2) contribution of web reinforcement to shear strength, and (3) to establish the minimum amount of web reinforcement required to prevent shear failuers. The following variables were included: type of loading, length of negative moment longitudinal reinforcement, percentage of web reinforcement, and grade of longitudinal reinforcement. Fifteen beams were designed with no web reinforcement, 13 beams hod the amount of web re-inforcement required by the 1951 ACI Code, and 24 beams were designed with more web reinforcement than required by the ACI Code. An analysis of the test results indicated good agreement with the calculated values for the loads at diagonal tension cracking, shear compression failure, and flexural failure, as computed with the aid of existing mathematical expressions developed from tests of simple and restrained beams. When the amount of web reinforcement was determined by equating the formulas for maximum flexural and maximum shear loads, it was found to be more than was necessary.