Title:
Effects of Aggregate Size on Properties of Concrete
Author(s):
Stanton Walker and Delmar L. Bloem
Publication:
Journal Proceedings
Volume:
57
Issue:
9
Appears on pages(s):
283-298
Keywords:
none
DOI:
10.14359/8021
Date:
9/1/1960
Abstract:
Research is described supplementing earlier work which indicated a lack of improvement in concrete strength resulting from increased maximum size of aggregate. The more recent program provided a broader range of classes of concrete and test variables for the purpose of checking the degree of applicabiliry of the earlier finding. The tests were made with maximum sizes of coarse aggregate ranging from 3/8 to 2 1/2 in., using three cement factors, from 4 to 8 sacks per cu yd, both with and without air entrainment. Compressive and flexural strength tests were made at ages of 7, 28, and 91 days, and specimens are available for test at 1 year. Tensile splitting tests were made at 28 and 91 days. Drying shrinkage measurements were also made on all concretes. Results indicate that increasing the maximum size of coarse aggregate may not necessarily be beneficial to con-crete strength. Drying shrinkage was not substantial1 increased by reduced size of aggregate down to about 8/4 in.