Title: Correlation Between Strength of Small- and Standard-Size Concrete Cylinders
Author(s): R. L. Day and M. N. Haque
Publication: Materials Journal
Appears on pages(s): 452-462
Keywords: cold-weather construction; compressive strength; curing; fly ash; specimens; Materials Research
This study presents an analysis of the influence of specimen size on the measured compressive strength of plain and fly ash concretes exposed to standard and cold curing. Strength tests were performed on three classes of air-entrained concrete using two sub-bituminous fly ashes at three replacement levels. Analysis of the present experimental results, combined with other results presented in the literature, shows that the compressive strength indicated by 75-mm cylinders is statistically identical to that indicated by 150-mm cylinders. Analysis suggests that this one-to-one relationship between strength of 75- and 150-mm cylinders may be valid for concrete strengths up to 50 MPa (7250 psi). Further analysis of published data leads to the conclusion that the equality of strength among specimen sizes also includes 100-mm- diameter cylinders. The type of mold used to cast test cylinders, whether cardboard, steel, or tin, does not have a significant effect on the trends observed.