Laboratory Tests Of Concrete Aggregate And Riprap PDF Download

Ledge rock from three commercial sources was tested for suitability for use as riprap, and material from one of the sources of ledge rock plus crushed aggregate were also tested for use as concrete coarse aggregate. Drilled 6-in.-diameter cores from two commercial sources were tested for suitability for use as riprap and concrete coarse aggregate. A coarse sand and a blending sand were tested for use as concrete fine aggregate. Crushed aggregate manufactured from each of the two cores and one of the ledge rocks was tested in combination with blends of the coarse and fine sand for freezing and thawing of concrete aggregate. Results of the petrographic examination and tests on five sources of carbonate rock for riprap are reported. Consideration of the results of the freezing-and-thawing tests conducted according to CRD-C 144 on three sources of carbonate rock, for use in concrete indicate similarity. However, it appears that the material from one company is preferable to the other because it is thicker bedded. Material from a nearby quarry was previously used in the Alton Lock and Dam and it is known to be a reactive carbonate rock. Reaction rims have been observed in the Alton concrete. Considerations of field behavior of the Alton concrete and laboratory testing for length change of the Alton concrete show that this is not an expansive reaction and no precautionary measures are required for its use. Evaluation of rock from the Columbia Quarry and the Riverview Quarry for potential reactivity indicated that the Columbia rock was not reactive. However, some of the ledge 3 Riverview rock is potentially reactive.