Conditions for laboratory tests for determining shear strength:
As we already know that there are three types of laboratory test for the determination of the shear strength which are:
- Direct Shear test
- Unconfined compression test
- Triaxial compression test
We know that shearing strength of the soil is greatly influenced by the loading conditions and the drainage conditions maintained during the test. On the basis of loading conditions and drainage conditions the laboratory tests are further divided into following three main categories:
a) Unconsolidated-undrained test (UU test) or Quick shear test:
It has comparatively low shearing strength.
b) Consolidated-undrained test (CU test) or Consolidated quick test:
In this method moisture is drawn out due to high pressure.
c) Consolidated-drained test (CD test) or slow test:
This method is used only for research purpose and has more money and time.
Usually UU and CU are performed in most of the projects in practical analysis of the site.