STATISTICAL COMPARISON OF PROPERTIES OF MANUFACTURED SAND-TO-MORTAR DURABILITY AND SCALING RESISTANCE

In this work, results of tests on rock aggregate and manufactured sand from Paleozoic carbonate rocks from quarries in southwest Ontario were compared to those of mortars containing manufactured sand. Aggregate tests included petrographic analysis, water absorption/adsorption, linear expansion under various conditions, thermal expansion, insoluble residue content, micro-Deval abrasion loss, freeze-thaw loss, and rate of settlement of -0.075 mm fraction. Mortar tests consisted of drying shrinkage, water absorption/adsorption, linear expansion under various conditions, thermal expansion, and freeze-thaw loss. Multivariate statistical techniques were used to compare and group the properties of aggregates and mortars. Factor analysis showed that the results could be grouped into 4 factors: 1) durability; 2) porosity; 3) thermal expansion; and 4) isothermal expansion factors. Stepwise regression predictive models of mortar resistance to salt scaling were developed, based on results of simpler tests on aggregates. K-cluster analysis successfully classified the aggregates and mortars made from them into good and poor categories. The tree analysis provides the passing limits that can be applied to aggregate tests of any defined group of aggregates.