CAPPING FOR COMPRESSION SPECIMENS1

Compressive strength tests have been made on tile capped with unretarded gypsum with neat Portland cement, with a mixture of three parts by volume of Portland cement to one part of unretarded gypsum and on tile whose bearings were ground. The tile whose bearings were ground gave the highest strengths. The interpretation of the results was based on the workability and yielding of the cap and on the influence of the bearing block. As it is impossible to grind the bearings of all types of tile, a cap of three parts of Portland cement to one part of unretarded gypsum is advocated as giving the highest and most consistent results.