mortar What''s the best ratio for sandonly concrete ...
Highstrength concrete is made by lowering the watercement (W/C) ratio to or lower. Bob Vila is looking at 6000 PSI (40 MPa) concrete for countertops. Three days after pouring a counter with Countertop Mix, the compressive strength of the slab will achieve resistance equal to 2,000 pounds per square inch (PSI).