STUDY OF BLOCK-DISCRETE-SPRING METHOD BASED ON CONTINUUM MECHANICS
FENG Chun1，LI Shihai1，YAO Zaixing1，2
(1. Institute of Mechanics，Chinese Academy of Sciences，Beijing 100190，China；2. School of Mechanics and Engineering， Liaoning Technical University，Fuxin，Liaoning 123000，China)
Abstract：A block-discrete-spring method based on continuum mechanics is presented and this method would be applied to simulate the progressive failure of geological body. The theoretical basis of this approach is continuum mechanics and the discrete object is regular hexahedron with 8 nodes. According to shape function theory of FEM and element stiffness matrix of regular hexahedron，12 edge springs are obtained，and the formula，spring stiffness，related displacement and physical meaning of each spring are presented. The elastic result achieved with this method is the same as that of traditional FEM，and on this basis，Mohr-Coulomb criterion and tensile criterion are introduced to calculate the failure of spring. If all springs in the block are broken，the block is treated as particles. Double judgement model is adopted to estimate the failure of block. The purpose of block failure judgement is to choose the potential failure plane for springs，while spring failure judgement is used to calculate the real spring force. Finally，the rationality of the failure result calculated by block-discrete-spring method is approved by some cases. The essence of block-discrete-spring method is to transfer the element of the traditional FEM to structure according to the 12 springs，by which，the inner failure character of block and the progressive failure process of geological body could be studied by analyzing the failure of springs.
