This International Standard describes tensiometer methods for determining pore water pressure in both unsaturated and saturated soils. The methods are based on in-situ measurements of pore water pressure in the field and for the determination of pore water pressure, e.g. B. applicable in plant containers or soil cores for experimental studies. At normal atmospheric pressure (ie about 100 kPa), the application of these methods is limited to a range of pressures to about -85 kPa. The range decreases at lower atmospheric pressure. Tensiometers cannot be used if temperatures below 0 °C occur at the measuring depth. Their accuracy is affected by temperature fluctuations in the ground and air. The setting time of tensiometers ranges from a few seconds to several days. Reliable measurements under outdoor conditions require regular maintenance of the tensiometers. Tensiometers provide point measurements of pore water pressure. In order to be able to measure the pore water pressure at different depths, several tensiometers are required. In the field, parallel sets of equipment are required if the spatial variability of the soil has to be taken into account.
EN ISO 11276:2014 history
2014EN ISO 11276:2014 Soil quality - Determination of pore water pressure - Tensiometer method