Triaxial cell for the testing of geomaterials in compression and in shear

A cell for testing geomaterials on cylindrical specimens, rock, ground, or materials manufactured on sampling sites, including at least one piston for subjecting a specimen to a load directed along the longitudinal axis of the specimen, said cell exhibiting two elements, subjected to the action of said at least one piston, respectively in contact with the bases of the specimen, each of said two elements is a heterogeneously deformable element, exhibiting two half portions which deform differently relative to one another when constrained, one half of the half portions being made of an elastomer, the other half portion being made of metal, each half having a contact surface with the specimen, wherein the contact surfaces of said two half portions are coplanar at rest, so that when said specimen is compressed by said at least one piston between the said two elements, the specimen is cracked, the crack extending longitudinally along the specimen from one said deformable element to said other deformable element.