The purpose of this investigetion was to study the durability characteristics of a river gravel, used as coarse aggregate for concrete, with respect to four major fractions separated in accordance to their general mineralogical classification. This aggregate was from the same stock of Ohio River gravel that was used in earlier phases of this Project reported in 1947.

Since this gravel consisted of several rock types varying in mineralogic constituents, it was conceivable that poor performance could possibly be attributed to some undesirable fraction or fractions, rather than to the aggregate as a whole. The separation of this aggregate was rather general yet satisfactory for the purposes of this study and was confined to four fractions in each of which there was a preponderance of one general rock type. These four fractions were designated, for convenience, as limestone, chert, quartzite, and granite.

Evaluation of durability characteristics was made by means of freezing and thawing tests on like samples of concrete made with the different gravel components. All other features of the concrete were kept as constant as possible.

Report Date


Report Number

No. 49

Digital Object Identifier