|
Abstract Material force method for simulating secondary structures in rock mass is innovated based on composite material mechanics considering the disadvantages of existing equivalent methods and discrete methods. In this method，rock is regarded as matrix，and secondary structures are regarded as inclusions. The mechanical effects of secondary structures are embodied in material forces induced by eigen strain. Based on the essence of analysis and calculation of elastoplastic mechanics，material force method is planted into elastoplastic finite element method with the adoption of a dual-mesh system for quadrature. Compared with equivalent methods，material force method takes both the difference of deformation properties and the difference of strength properties between rock and secondary structures into consideration. Compared with discrete methods，the complication of pre-processor is reduced at great scale because its sub-meshes for quadrature are completely independent of the finite element meshes. In addition，calculating the material force induced by eigen strain step by step is the same essence of material force method and elastoplastic FEM. Therefore，the extra cost caused by material force method is minimized while keeping total degrees of freedom unaltered. The validity and effectiveness of material force method are shown by two examples.
|
|
Received: 11 March 2009
|
|
|
|
