90 



MECHANICAL PROPERTIES. 

 TABLE 68. — Cement and Concrete. 



Note. — (From Bureau of Standards Tech. Paper 58.) Neat cement briquettes mixed at 

 plastic consistency (water 21 per cent) show 0.52 kg/mm^ or 740 Ib/in^ tensile strength at 28 

 days' age; 



I Cement: 3 Ottawa sand-mortar briquettes, mixed at plastic consistency (water 9 per 

 cent) show 0.28 kg/mm^ or 400 Ib/in^ tensile strength at 28 days' age. 



Smithsonian Tables. 



