Different types of field shear tests:
While working in field we may encounter many problems such as undisturbed sampling of non-cohesive soil and soft sensitive clay. They are considered impossible, and even if possible, still it is very difficult and very expensive. Usually shear strength of all such soils is determined by field shear tests. Now a days we are familiar with many varieties of shear field tests which are conducted for this purpose. Several very common routine tests are as follow:
- Standard penetration test, spt ( astm d 1586):
This process is preferred because it provides a fairly good estimate of the shear strength of the non-cohesive soil.
- Cone penetration test, cpt ( astm d 3441):
It is used for the soft clays and loose to medium dense sands.
- Field vane shear test, fvst ( astm d 2573):
- Pressure meter test, pmt (menard 1956):
It is used for a large variety of soils and rocks.