Talk:Direct shear test

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A Direct Simple Shear test (or a Simple Shear test) is actually quite different from a Direct Shear test.

The most important difference is the number of rings in which the sample is placed. The Direct Shear uses two rings (as described in the article) while the DSS test uses a large number of rings, or even a rubber membrane to contain the sample. The top cap is displaced using a horizontal force while the vertical force is kept constant (or the sample height is kept constant, depending on the type of testing) This leads to a more or less uniform shear stress in the sample, while the direct shear test forces a failure plane to develop.

As you can see: Quite different tests, and especially for organic soils there will be signifant differences in the test results also.