Auxiliary mounting device for biaxial compression test of thin plate type non-standard test piece

The utility model relates to an auxiliary mounting device for a biaxial compression test of a thin plate type non-standard test piece. The auxiliary mounting device comprises an upper bracket, a vertical rod, a lower bracket, a positioning rod and a contact, the upper supports and the lower supports are of cuboid structures, the two upper supports are symmetrically fixed to the two sides of an upper pressing plate of the biaxial compression testing machine, and the lower supports are correspondingly fixed to the two sides of a lower pressing plate of the biaxial compression testing machine. Reserved holes are formed in the upper supports, and the two vertical rods penetrate through the reserved holes in the upper supports on the two sides to stand between the upper supports and the lower supports. Two parallel positioning rods are horizontally fixed on each vertical rod, a contact is arranged at one end, close to the inner side, of each positioning rod and used for being in contact with a test piece, and the