Title: Creep of Concrete at Temperatures from 70 to 450 F Under Atmospheric Pressure

Author(s): K. W. Nasser and H. M. Marzouk

Publication: Journal Proceedings

Volume: 78

Issue: 2

Appears on pages(s): 147-150

Keywords: atmospheric pressure steam curing; compressive strength; concretes; creep properties; creep recovery; creep tests; curing; high temperature tests; research; stress-strain relationships; temperature.

DOI: 10.14359/6933

Date: 3/1/1981

Abstract:
This paper presents results of creep and creep recovery of concrete specimens heated under atmospheric pressure at six different temperatures ranging from 70 to 450 F (21 to 232 C) for over 11 months. At each temperature, three stress levels are applied. The results are compared to the corresponding results of a previous investigation on iden- tical mass concrete. In general, creep strains increase with a rise in temperature, reach a maximum at 160 F (71 C), and then decrease with further rise in temperature. The creep strains at 160 F (71 C) are about three times those at 70 F (21 C) and are much smaller than the corresponding ones of mass concrete. In some cases, the creep of sealed concrete is five times greater than the creep of unsealed concrete, all other things being equal. The relation of creep to stress-strength ratio is linear. Discussion of a hypothesis of the creep mechanisms is presented.