Strength index tests

To determine the undrained shear strength of soil several different strength index methods can be employed both in the field as well as under laboratory conditions. The field tests, i.e. torvane and pocket penetro, which are also common practice during soil description in the laboratory, give only an basic indication of the undrained shear strength. More accurate strength index methods, i.e. the laboratory vane test (Labvane) and the fall cone tests, are only to be conducted under laboratory conditions.