Title:
Evaluation of Internal Restrained Strain in Concrete
Members at Early Age
Author(s):
H. R. Lu, S. Swaddiwudhipong, and T. H. Wee
Publication:
Materials Journal
Volume:
97
Issue:
5
Appears on pages(s):
612-618
Keywords:
adiabatic; formwork; restraint (of concrete); strain
DOI:
10.14359/9294
Date:
9/1/2000
Abstract:
The temperature rise in concrete was measured under adiabatic conditions. The maximum temperature rise and temperature differential in concrete elements at early age are estimated using the profile of adiabatic temperature rise and the theory of heat transfer. This study looks at how concrete mixtures, concrete element dimensions, and types of formwork affect the maximum temperature rise and temperature differential. This paper explains how the modification factor for calculating the internal restrained strain is related to creep, shrinkage, and thermal strains, and how the internal restrained strain in the core or on the surface is induced by the temperature differential between the core and surface of concrete elements. Consequently, the authors determine the value of the internal restraint factor to be 0.36.