Abstract:

An apparatus for specimen preparation and test on contact behaviour of idealized bonded granules is designed, which can be applied into the verification of contact model and parameter rationality for natural structured sand in the discrete element method (DEM). By using the specimen preparation devices, two aluminum rods with the same size are glued together by adhesive in a pre-defined mode. By using the auxiliary loading devices, the mechanical behaviours of contact between the bonded rods are obtained under simple and complicated conditions. The results show that the apparatus can be used effectively in test on contact behaviour of the bonded rods. The mechanical behaviours of contact between bonded rods agree well with the bonded materials contact model implemented by the discrete element method. The peak shear and rotational strength of the bonds increase with the increasing of normal force. The strength envelope in the normal-torsion-shear stress space is an elliptic paraboloid shell.

Key words: bonded granules, contact behaviour, complex loading condition, experimental apparatus