Pumice aggregate, which has high reserves in our country, is used in the production of lightweight concrete, however, it is not preferred as a structural lightweight concrete since its low mechanical properties. The mechanical properties of pumice aggregates can be improved by coating their surfaces. In this way, the coated pumice aggregates can be used to produce lightweight concrete. This study investigated the coating potential of Kayseri and Ahlat pumice aggregates with cement paste. The flow diameter, marsh funnel, and 28-day flexural and compressive strength values of the cement paste 0.55-0.50 w/b ratio and 0.35-0.30 w/b ratio with 1.5% plasticizer admixture were determined. At the end of 28-day curing, the Coating effectiveness of the produced samples was investigated via optical microscope, aggregate impact value, water absorption, and unit weights, and comparisons were made with uncoated aggregates. After coating, it was determined that Ahlat and Kayseri pumice aggregates were crushed by 11% and 18%, considering the impact strength result, moreover a decrease in water absorption was obtained by 50.49% and 78.32%, respectively. As a result, the water absorption values of the coated pumice aggregates decreased, and the aggregate impact values increased compared to the uncoated pumice aggregates.
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