COLLAR FOR MEASURING THE SIDE DEFORMATION OF A TEST DURING COMPRESSION TESTS, IN PARTICULAR UNIAXIAL OR TRIAXIAL TESTS

摘要

The invention relates to a collar (1) for measuring the lateral deformation of a test piece during uniaxial or triaxial compression tests. According to the invention, the collar consists of a metal ring (2) or a ring composite materials, able to grip said open test piece, and whose free ends are separated by a distance Delta, said collar further having means (5) for measuring, directly or indirectly, the spacing Delta, said free ends (3) of the ring (2), constituted by a probe (6) of the linear variation differential transformer type.The invention also relates to a protective sheath for test piece adapted to cooperate with the collar.