Microscopic back analysis method of continuum damage model based FEM

This work presents a direct back analysis method of CDM-FEM. A relative fracture rule is used to make the method have nondimensional property for failure process simulation. The method can perform fracture progress analysis without setting micro strength parameter in advance. Examples of obtaining micro tensile parameter from conventional tests are performed to illustrate how the back analysis method works. Except obtaining micro parameter, the method is also be used to study some important aspects of CDM-FEM. The mesh size effect of CDM-FEM is studied through this method. It is reported that a unique mesh size is needed to reproduce the correct relationship of fracture toughness and tensile strength. Moreover the critical mesh size can be determined by using the proposed method. Finally, fracturing law used in CDM-FEM is also studied through the method.