BS EN ISO 11272:2017 pdf download

BS EN ISO 11272:2017 pdf download.Soil quality — Determination of dry bulk density
1 Scope
This document specifies three methods for the determination of dry bulk density of soils calculated from the mass and the volume of a soil sample. The methods involve drying and weighing a soil sample, the volume of which is either known [core method (see 4.1)] or determined [excavation method (see 4.2) and clod method (see 4.4)].
4.1.3 Sampling and drying
Press or drive a core sample holder (4.1.2.1) of known volume without deflection and compaction into either a vertical or horizontal soil surface far enough to fill the sampler. Carefully remove the sample holder and its contents to preserve the natural structure, and trim the soil extending beyond each end of the sample holder with a straight-edged knife or sharp spatula. The soil sample volume is thus equal to the volume of the sample holder. Take at least six core samples from each soil layer. Place the holders containing the samples in an oven (4.1.2.2) at 105 °C until constant mass is reached. NOTE 1 In most cases, constant mass is reached after 48 h drying. Remove the samples from the oven and allow them to cool in the desiccator (4.1.2.3). Weigh the samples on the balance (4.1.2.4) immediately after removal from the desiccator (m t ). Control mass is reached when the differences in successive weighings of the cooled sample, at intervals of 4 h, do not exceed 0,01 % of the original mass of the sample. Swell/shrink soils (especially clays, muds and peats) change their bulk density with changing water content. Such soils should be sampled first in a moist state (i.e. field capacity); in addition, they should be sampled in a wetter state (water saturation) and in a drier state (i.e. wilting point). If the dry soil is too hard to be sampled, the bulk density of the soil can be determined according to 4.3, and the total soil volume according to 4.2.3.NOTE 2 If bulk density (and water content) is the only parameter of interest, it is not necessary to keep the samples in their holders when taking them back to the laboratory. After the sample has been obtained and trimmed, the soil can be extracted from the holder, without loss, in order to be stored for transportation either in a metal box or in a heat-resistant plastic bag. It is normally worthwhile to combine a measurement of the water content with a measurement of the bulk density; in that case it is necessary to transport the samples without allowing loss of water by evaporation, and to begin the laboratory operations by weighing the fresh sample.