Title:
Concrete Strength in Structures
Author(s):
Delmar L. Bloem
Publication:
Journal Proceedings
Volume:
65
Issue:
3
Appears on pages(s):
176-187
Keywords:
age;compressive strength;concrete cores;concretes;curing strength;quality control;testing.
DOI:
10.14359/7465
Date:
3/1/1968
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 1 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: (1) 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.