Laboratory Analyses Consultancy Services

Grain size distribution
To determine the grain distribution of a sample, the sample is subjected to preliminary processing and then guided through sieves with varying mesh sizes. The result of sieving a soil type can be expressed in the form of a grain size distribution diagram, also known as a sieve curve. The diagram shows which proportion of a grain mass, expressed on weight percentages, is smaller in total than a given diameter. The aerometer test is used for fine particles (2 – 63 µm). A steep curve shows that the soil type is uniform in terms of grain size. A gentle curve, on the other hand, shows that there is a variety of grain sizes.

Groundwater analysis
The first step in designing a groundwater system is to take water samples and send them to a laboratory. The results of the groundwater analyses are used for the design. The properties of the groundwater are important to the choice of materials. The requirements of salt water are different from those of fresh water, for instance.

Degasification pressure tests
Groundwater contains dissolved gases. Depending on the course of the pressure in the groundwater system, the gases can reform and create small bubbles. This is called degasification and can cause blockages in the wells when the water is returned to the soil. That is why it is important to determine the degasification pressure for the design of the system. A special technique is used to pressurise groundwater samples. These stainless steel cylinders are sent to TNO for analysis. The degasification pressure is then calculated on the basis of the analysis results.