A Preliminary Study On Numerical Test Of Mechanical Properties Of Coarse Granular Materials Considering Particle Breakage

Coarse granular materials are granular aggregates composed by different sizesand properties of rock particles, which are easy to break under loads. The particlebreakage affects mechanical properties of coarse granular materials. Accuracy anduniversality of physical tests are influenced by limitations of test conditions.Numerical tests are effective complement for physical tests due to without thelimitations. This paper carried out the numerical test on mechanical properties ofcoarse granular materials considering the particle breakage using two-dimensionalDDA (Discontinuous Deformation Analysis). The main research work and results are asfollowing:(1) DDA numerical model for the test of mechanical properties of coarsegranular materials was established and reasonable calculation parameters such ascontact stiffness, time step and damping were studied.(2) The particles of coarse granular materials were subdivided by the finiteelement refinement technique of the ANSYS software for the needs of simulating theparticle breakage.(3) The Block Jacobi-PCG and parallel computing technique were used to solveDDA equations for speedup of the numerical test.(4) Numerical test results considering the particle breakage were in overallclose to those by triaxial tests. But the stress-strain curves by the numerical testwithout considering the particle breakage were much higher than those consideringthe particle breakage, which shows that the consideration of the particle breakage isnecessary.The above studies laid a foundation for DDA numerical test of mechanicalproperties of coarse granular materials.