Study on the correlation between normal coefficient of restitution and contact parameters in rockfall modeling using discontinuous deformation analysis

摘要

This paper presents a study on the correlation between normal coefficient of restitution (COR) and contact parameters in rockfall modeling using three dimensional discontinuous deformation analysis (DDA). Original DDA codes use the viscoelastic contact model for contact force calculation. The contact parameters of the viscoelastic contact model, such as normal stiffness and damping constant, affect the computation results observably. Though DDA method has been proposed for more than twenty years, these contact parameters in DDA modeling are still difficult to determine in collision dynamics. Coefficient of restitution (COR) is considered as the critical parameter to evaluate the motion state after collision between two blocks. In this research, normal COR is used for evaluating calculation results of rockfall modeling with 3D DDA. According to the results of more than one hundred numerical simulations based on laboratory tests, relation curves between parameters of viscoelastic contact model and normal COR are presented.