Title: Shear Strength of Reinforced Concrete Beams Part 1 -Tests of Simple Beams

Author(s): K. G. Moody, I . M . Viest, R. C. Elstner, and E. Hognestad

Publication: Journal Proceedings

Volume: 51

Issue: 12

Appears on pages(s): 317-332

Keywords: no keywords

DOI: 10.14359/11680

Date: 12/1/1954

Abstract:
Data are presented on the shear strength of 42 simple beams, 40 without web reinforcement and two with web reinforcement. Tests were carried out in three series with the following variables: (1) percentage of longitudinal and web reinforcement, .and method of anchorage; (2) size and percentage of longitudinal reinforcement and strength of concrete; and (3) concrete mixture and method of curing. The size of specimen was different for each of the three series. The beams were tested with one or two concentrated loads and all failed in shear after one or more diagonal tension cracks formed in the region of maxi-mum shear. The magnitude of the loading causing the initial diagonal tension cracks depended primarily on the cross section and the concrete strength. Most beams were able to sustain greater loads than the cracking loads. Magnitude of failure loads depended on cross section dimensions, amount of longitudinal reinforcement, amount of web reinforcement, strength of concrete, and length of shear span. Failure was by destruction of the compression zone of concrete above the diagonal tension crack and adjacent to a loading block. Test results indicated that strength of beams with large u-d ratios may be governed by the load causing first cracking whereas the strength of shorter beams is governed by the load causing the destruction of the compression zone or concrete. Results also indicate that the load at first cracking may be predicted on the basis of nominal shearing stress and the ultimate load may be predicted on the basis of ultimate moment.