The European Standard EN 196-1 specifies that the cement resistance is determined by compression tests on prismatic mortar specimens with dimensions 4 x 4 x 16 cm, produced with normalised sand mortars in the radio 3 to 1 by weight with respect to the cement used.
The precedent of the normalised sand in Spain dated back to 1956 when the first processing factory of normalised sand coming from Spanish quarry was set up in the Institute. In 1960 it is published in the B.O.E. nº 22 y nº 187 that test to determine the mechanical compression of cements should be conducted with normalised sand produced in the factory of the Institute. The normalised san with standard EN 196-1 was given the AENOR mark in 1990. The Institute stopped producing the normalised sand in 2000, although at present it continues commercializing normalised sand coming from others producers (sand CEN standard EN 196-1). The grain size distribution of this sand is represented in the attached graphic.
