Procedure—As soon as the cube specimens have been
dried (12.3), determine their compressive strengths. (If density is to be determined, do so at this time. (See Section 13)).
Position the cubes in the testing machine so that the load is
applied on surfaces formed by faces of the molds, not on top
and bottom. Apply the load continuously and without shock, at
a constant rate within the range 15 to 40 psi/s. Do not exceed
40 psi/s ((275 kPa)/s) after 50 % of the maximum load has
been reached.