Title: Under-Reinforced Concrete Beams Under Long-Term Loads

Author(s): Herbert A. Sawyer, Jr. and Jack E. Stephens

Publication: Journal Proceedings

Volume: 54

Issue: 7

Appears on pages(s): 21-29

Keywords: no keywords

DOI: 10.14359/11424

Date: 7/1/1957

Abstract:
Effect of an increase in the time of application of load on both deformations and strength of under-reinforced concrete beams is reported. Intermediate grade steel and concrete of 2500 psi and 5000 psi nominal strength were used for the 14 test beams loaded with gravity-type loads. Increase in term of loading had slight effect on ultimate strength. All test strengths, regardless of term of loading, exceeded strengths calculated by the common ultimate load theories. Increase in term of loading caused important modifications in the moment-curvature relationship, including large increases in concrete strain and beam curvature at ultimate load.