BS EN 12390-7:2019 pdf free.Testing hardened concrete.
4 Apparatus 4.1 Callipers and rules, with a maximum permissible error of 0,5 % of the dimension, for measuring the dimensions of the specimens. 4.2 Balance, equipped with a stirrup for weighing the specimen in both air and water with a maximum permissible error of 0,1 g of the mass. 4.3 Water tank, fitted with a device to maintain the water at a constant level and of sufficient size to allow the specimen on the stirrup to be fully immersed to a constant depth (see Figure 1). If the reading of the balance is affected to within the accuracy required due to the displacement of water when immersing the specimen, then the tank should be fitted with a device to maintain the water at a constant level. The tank should be of sufficient size to allow the specimen to be fully immersed. 4.4 Ventilated oven, in which the temperature is capable of being controlled at (105土5)°C. NOTE The apparatus required depends upon the method selected for determining the volume of the specimen. 4.5 Moist cloth.6.1.2 Determination of volume This European Standard recognizes three methods for determining the volume of the specimen:
a) by water displacement (reference method); b) by calculation using actual measurements; c) for cubes, by calculation, using checked, designated dimensions. NOTE 1 The precision of the method depends on the method selected for measuring the volume of the specimen. Measurement of volume by the water-displacement method is the most precise, followed by calculation
using measurement of actual dimensions and lastly calculation using checked, designated dimensions. NOTE 2 The limitation to cubes in 6.1.2 c) of using designated dimensions in calculation of volume is due to the greater tolerance on length, according to EN 12390-1, of other specimen shapes.Dry the specimen in a ventilated oven at (105土5]) °C until the mass changes by less than 0,2 % in 24 h. Before each weighing, cool the specimen to near room temperature in a dry airtight vessel or desiccator. Record the value of the oven-dried mass m。as indicated, in kg.BS EN 12390-7 pdf download.