Title:
It's Time for a Change from 6 x 12- to 3 x 6-in. Cylinders
Author(s):
K. W. Nasser and A. A. Al-Manaseer
Publication:
Materials Journal
Volume:
84
Issue:
3
Appears on pages(s):
213-216
Keywords:
aggregate size; coefficient of variation; compression tests; compressive strength; concretes; cylinders; specimens; standard deviation; Materials Research
DOI:
10.14359/1939
Date:
5/1/1987
Abstract:
This paper presents the results of a study that was carried out to compare the compressive strength of 3 x 6-in. (75 x 150-mm) cylinders rodded 10, 15, 20, or 25 times in two layers with that of 6 x 12-in. (150 x 300-mm) cylinders rodded 25 times in three layers. The tests were carried out on concrete made with Type I cement and aggregate of maximum size of 1.0 in. (25-mm). The strength tests were performed at 1, 3, 7, 14, 21, 28, and 56 days. The conclusion from this study is that the 3 x 6-in. (75 x 150-mm) cylinder rodded 10 times in two equal layers is a satisfactory specimen to determine the potential strength of concrete. Since the 3 x 6-in. (75 x 150-mm) cylinder has a larger coefficient of variation than that of the 6 x 12-in. (150 x 300-mm) cylinder, use of a greater number of specimens per test is recommended.