Title: Effect of Temperature, Stress Level, and Age at Loading on Creep of Sealed Concrete

Author(s): J. Komendant, V. Nicolayeff, M. Polivka, and D. Pirtz

Publication: Symposium Paper

Volume: 55

Issue:

Appears on pages(s): 55-82

Keywords: adiabatic conditions; age; compressive strength; creep prop-eeptests; curing; high strength concretes; high temperature;loads (forces); modulus of elasticity; nuclear reactors; poisson ratio;pressure vessels; prestressed concrete;

DOI: 10.14359/6609

Date: 8/1/1978

Abstract:
concrete ra-Creep tes ts were performed in high-strength sealed to evaluate the effects of va ious combinations of temperature, stress level, and age of loading. Test conditions included temperatures of 73, 110, and 160F (23, 43, and 71C), stress levels of 30, 45, and 60 percent of compressive strength, and ages of loading of 28, 90, and 270 days. The creep loads were maintained for over one year, with creep recovery observed on selected groups of specimens for a period of 90 days. Tests were made on two concrete mixes, each made with the same brand of cement and sand but different coarse aggregates. The nominal strength of the concrete at age 60 days was 7500 psi (527 kgf/cm2) for moist-cured specimens and 7000 psi (492 kgf/cm2) for sealed specimens. Also reported are results of tests made to determine the effect of testing temperature on compressive strength as well as the influence of thermal cycling between 73 and 16OF (23 and 71C) on strength and elastic properties.