Title:
Effect of Various Coarse Aggregates Upon the Cement-Aggregate Reaction
Author(s):
C. H. Scholer and W. E. Gibson
Publication:
Journal Proceedings
Volume:
44
Issue:
6
Appears on pages(s):
1009-1032
Keywords:
none
DOI:
10.14359/12205
Date:
6/1/1948
Abstract:
Concrete made with native Kansas sand-gravel (an aggregate containing little coarse material) began, about 1930, to show abnormal expansion, map cracking and loss in flexural strength. Tests were made by the Engineering Experiment Station at Kansas State College, in cooperation with several other agencies, to determine the causes of and prescribe cures for this condition. Concrete samples were made with 24 different cements using two trouble-making aggregates and were submitted to varying exposure tests. It was found that deterioration varied with the different cements, but there was no consistent relation between cement composition and extent of deteriorarion. Hence it was concluded that the cement-aggregate reaction causing deterioration was not primarily an alkali-aggregate reaction. Extensive tests on concrete made of sand gravel combined with some coarser aggregates indicate reduced expansions and less tendency toward deterioration. Addition of 25 percent or more (by weight) coarse limetone is adequate sandstone, as much as 40 percent may be required.