The shape of rockfill material paticle is highly complicated

and there is an obvious charateristic of grain crushing.To eliminate the influence of paticles′shape on the dynamic characteristics of rockfill material

the study of dynamic triaxial test on crystal ball was conducted under the condition of without considering particle breakage

and the influence of test confining pressure on dynamic elastic modulus of crystal ball was analysed.Based on the results of dynamic triaxial test

mesoscopic simulation was carried out.Study shows:the change law of dynamic elastic modulus of both crystal ball and rockfill material is identical basically

three-dimensional particle flow program can simulate the dynamic elastic modulus of this kind of material;along with the increase of grain diameter span

the sample grading relationship enhances

and the maximum dynamic modulus of elasticity increases

both diminishing the diameter of the small particles and largening the diameter of the big particles can lead to increase of the maximum dynamic modulus of elasticity.Along with the increase of mesoscopic shear modulus

the dynamic modulus of elasticity increases according to approximate power function relationship and the dynamic strain decreases.