Abstract：Deformable block discrete element model is studied on the basis of three-dimensional rigid block discrete element method，and corresponding program is developed for this method. Each block element is considered as an elastic body，and finite element grids are generated. Each node displacement in the deformable block is calculated under the condition of force boundary. Jointed elements are constructed to transfer the force and displacement between adjacent deformable blocks. Jointed elements in the method can represent practical joint characteristics and strength in rock engineering. This method reflects the characteristics of continuous calculative method before breakage of structural plane. If the structural plane is broken，the jointed element will change into the normal and shear springs at the preset joint. So it also reflects the characteristics of discontinuous calculation method. In addition，the jointed element has certain thickness，so the calculative parameter can be determined by those of the actual joint. It embodies the improvement to rigid block discrete element method. Compared with rigid block discrete element method，this method can reflect the deformable character of rock，such as Poisson¢s effect of rock mass and the propagation velocity of stress wave in three-dimensional rock mass. Compared with finite element method(FEM)，it presents the jointed characteristics of rock mass more sufficient than FEM，and allows large displacement of element. Moreover，it can simulate the failure evolution process of the structural surface. Compared with the former discrete element model of deformable bodies，it overcomes the complicated calculation induced by finite difference method and is also three-dimensional discrete element model. So it provides an available numerical analytical method for geotechnical engineering.
