The standard œdometric test (incremental œdometer) is a very old test (Terzaghi, 1925) which is still carried out today. It has several drawbacks, particularly the inaccuracy in the determination of the preconsolidation stress and the length and complexity of the procedure. The constant rate loading test (CRS) avoids these two problems, but it is not yet considered as a standard test.

An initial research project (VSS 1999/285) has shown great interest in this procedure. It has also led to a literature search, develop theories of primary consolidation, conduct comparative tests and develop a test procedure. However this research has been carried out on reconstituted samples. In order to introduce this procedure, as a standard œdometric test and as a basis for the drafting of an SN standard, tests on undisturbed samples are still needed.