Multi Scale Analysis Of Progressive Damage And Fracture Failure For Composite

Composite materials have good mechanical properties, but the failure analysis is also complex. Based on meso and macro mechanics respectively, multi scale analysis is conducted to study the failure behavior of fiber reinforced composites. This dissertation contains three parts, namely micromechanics progressive damage analysis, micro crack propagation analysis and macro structure failure analysis.For the progressive damage analysis, the meso finite model of fiber reinforced composite is established in ABAQUS/Explicit modular with the consideration of meso mechanics and damage mechanics. And the damage evolution processes of the finite model under different external loads are analyzed respectively. Then the simulation of critical damage strain of RVE model for different fiber volume content is conducted, and the effect of fiber content to the material damage is also studied.For the crack propagation analysis of composites, the XFEM is used to study the propagation of sub-interface crack. The propagation progress is analyzed in detail through the extraction of internal energy, stain energy and dissipation energy of the structure. Then the interface delamination analysis is also carried out by VCCT, and the simulation results and SEM test results are compared. The strain energy release rate is used to study the details of interface crack propagation.For macro structure failure analysis, the filament wound composite cylinders are used as the research object. Firstly, the axial tensile modulus is calculated to analyze the axial tensile properties of composite cylinders with different winding angles. Then, the failure modes and loads of the composite cylinders are obtained by the axial tensile failure experiment. Finally, by using the subroutine function of ABAQUS, failure criterion is implemented to simulate the failure behavior and to calculate the capacity of the structures.