Sand shearing peculiarities using direct shear device

Abstract

An experimental investigation of the shearing conditions and their influence to the strength properties of Klaipėda sand by the universal shear device is presented. The shear tests for the loose and dense soils were realized for constant vertical stress (q = const.) and for constant sample volume (h = const.), respectively. Loading was supplied on the top of the sample. The testing conditions realized the cases of the constant and variable gap between upper and lower shearing ring. The stability of the gap between the upper and the lower shearing rings and that of the vertical load indicator of compression were measured during the tests. The measurements of the gap between the upper and the lower shearing rings resulted that it is not constant during the tests. The compression measurement tests of vertical load indicator it was found that full bridge type indicators are not proper for tests because of their deformability. The angle of the internal friction φ and the cohesion c depends on: density of soil; testing method; gap behavior factor: is it fixed or not.