EFFECTIVENESS OF DIFFERENT METHODS OF MAKING ABSORPTION DETERMINATIONS AS APPLIED TO HOLLOW BUILDING TILE1

Abstract

The experimental work consisted primarily in selecting specimens from hollow tile from seventeen sources and saturating them for the absorption determination by (1) immersion in water at room temperature for various periods ranging from fifteen minutes to nine days, (2) boiling for various periods ranging from 1 hour to 5 hours and then cooling in water at room temperature for at least one hour, and (3) repeated vacuum treatments. The true porosity for some of the specimens was then obtained from the specific gravity and the per cent saturation reached by the various methods was calculated. The results show that the five-hour boiling treatment gives results 1.2 greater than 72 hours immersion in cold water for the shale tile, 1.35 greater for the fire clay tile, 1.20 greater for the surface clay tile, 1.25 greater for the mixed clay tile and 1.28 greater for an average of all tile. They also show that the cold water immersion treatment gives 73.5 per cent saturation, the boiling treatment 92.7 per cent saturation, and the vacuum treatment 97.0 per cent saturation. In general the paper shows that the most consistent and practical way of determining the absorption of hollow tile is by boiling for five hours and then cooling for at least one hour before the saturated weight is taken.