Compression tests

Oedometer

MOS Grondmechanica B.V. has 34 machines for conducting compression tests at its disposal. Of these, 4 are fully automatic. With the latter, experimental tests can be potentially conducted faster. Naturally, this is not in accordance with the standards and regulations, but it is certainly usable for an experienced advisor. The compression test examines the settlement behaviour of the soil. For this purpose, an undisturbed sample is taken from the soil layer. The extent of compression depends on the level of stress and the compression properties of the layer in question. The speed with which the settlement occurs depends on the consolidation properties. For this, so-called Cv values are determined. MOS Grondmechanica B.V. works with a software package developed in-house for conducting and devising tests.

Constant Rate of Strain (CRS)

MOS Grondmechanica B.V. also has a CRS machine at its disposal. With this machine, a new type of compression test can be conducted in which the sample can be deformed within a rigid ring (K0-conditions) at a constant speed. With this unloading and reloading, relaxation( incremental phases) can be added to the test. A large benefit is that there is a constant measurement of points, therefore the preconsolidation stress can be measured more accurately from a fluent (continuous) line. Preconsolidation stress is the maximum effective vertical overburden stress that a particular soil sample has sustained in the past.

This test is mainly used in projects where an accurate estimate of the settlement is important. Both soft, cohesive soils (clay and peat), but also non-cohesive materials such as sand can be tested. The CRS-test is particularly suitable for the abc-isotaches method.