Title: Relaxation of Stress in Concrete and Its Relation to Creep

Author(s): J. J. Brooks and A. M. Neville

Publication: Journal Proceedings

Volume: 73

Issue: 4

Appears on pages(s): 227-232

Keywords: coarse aggregates: creep properties; creep recovery: creep tests; expanded clay aggregates: expanded shale aggregates; fly ash; lightweight aggregate concretes;regression analysis: stress relaxation: stress relaxation tests;stresses: water-cement ratio.

DOI: 10.14359/11070

Date: 4/1/1976

Abstract:
Stress relaxation data have been obtained for a range of lightweight aggregate concretes. For mixes having equal cement paste content, the loss of stress at any time is approximately proportional to the initial stress and inversely proportional to strength at the time of application of load. The process of stress relaxation at a constant strain is faster than creep under a constant stress, and, from an analysis of data of other investigators, the re-laxation ratio and creep coefficient appear to be related by an expression which is sensibly independent of the aggregate type, the mix proportions, and the storage environment. This relation can be accounted for by the rate of creep method when an allowance is made for creep recovery.