Title:
Landmark Series: Concrete Strength in Structures
Author(s):
Delmar L. Bloem
Publication:
Concrete International
Volume:
26
Issue:
6
Appears on pages(s):
30-41
Keywords:
DOI:
Date:
6/1/2004
Abstract:
The significance of concrete compressive strength measurement by various methods was investigated. Pairs of slabs from three concretes were subjected to good and poor curing. Cores and push-out cylinders were removed at six ages up to I year and tested for strength. Corresponding tests of molded cylinders brought the total specimens to 216 cores, 216 push-out cylinders, and 270 molded cylinders. The data indicate that two concepts of strength should be distinguished: (I) strength as a measure of load-carrying capacity in structures, and (2) strength as a measure of concrete quality and uniformity. The relation of the latter (determined by standard cylinder tests) to the former (determined on cores from the structure) is extremely variable.