Coupling method of three-dimensional DDA-FEM and its application

A numerical model that coupled three dimensional discontinuous deformation analysis(3D DDA) with finite element method was presented.The displacement field and the stress field were solved by proper internal discretization of deformable blocks using finite element meshes.The contacts between the deformable blocks were modelled with DDA method.Based on the variational principle of minimum potential energy,the global equilibrium equations of the coupling method was established.The contact matrix and friction force matrix were derived and added to the global equations.The problem of interaction of the concrete foundation and the elastic base was analyzed to illustrate the application of the proposed method.The numerical results demonstrated the validity and the advantages of the coupling method.