Plastic Limit And Shakedown Analyses Of Metal Matrix Composites And Structures

The purpose of this work is to perform plastic limit and shakedownanalyses of ductile composite materials and structures from the microscopicand macroscopic scales, which provides an effective approach for the strengthanalysis of ductile composite materials and structures.From the microscopic scale, a mathematical programming formulation andsolution algorithm for the static limit analysis of periodic ductile compositematerials are established. A Representative Volume Element (RVE) is chosento reflect the microstructure of composite. By introducing the generalizedmethod of cells (GMC) into the static limit theorem, the numerical model ofthe static limit analysis is formulated as a nonlinear mathematicalprogramming with constraint conditions, which can be effectively solved bythe Sequential Quadratic Programming (SQP) method.Based on the microscopic analysis of composite materials, a numericalmethod for the plastic limit and shakedown analyses of composite structures isestablished on the macroscopic scale. Hill's yield criterion is applied as themacroscopic strength criterion of composite. Quasi-conforming elements areused to get the elastic stress field and the self-stress field is constructed bythermo-parameters method. Thus the static limit and shakedown numericalformulation of orthotropic composite structures are obtained. Some researcheson these composite structures are carried out.