Study of the wearability and polish resistance of Oklahoma's coarse aggregates - final report

Abstract

This report describes a laboratory attempt to evaluate the wearability and polishing characteristics of "nonpolishing" stones when blended with a sound, polish susceptible stone. The effects of crystallinity, grain size, cementing strengths , mineralogy, and other petrographic features upon the wearability and polish resistance of aggregates are discussed. The usefulness of "nonpolishing" stones in blends was found to depend on the soundness or wearability of the stone as well as its resistance to polishing. Quartz sandy limestones and sandstones with L.A. abrasion wear loss of 40 percent or less were found to exhibit good resistance to both wear and polish. Relatively pure limestones (< 10% insoluble residue) which resists polishing were found to generally be lesser sound stones than the polish susceptible stone with which they were blended. The resultant faster rate of wear of these less sound stones makes these aggregates dubious for use in blends. The main contributors to skid resistance of chert and quartz were found to be edges and their resistance to wear and polish.