非一致随机分布复合材料力学参数预测的统计二阶双尺度方法

通过建立统计的二阶双尺度计算方法，预测了非一致随机分布复合材料结构的力学参数，包括刚度参数和弹性极限强度参数.所谓非一致随机分布复合材料结构，是指在整个结构中夹杂随机分布，但分布特征并不是处处相同，而是逐渐变化的，从而导致材料在宏观上具有随着位置连续变化的力学性能.描述了一致和非一致随机分布复合材料结构的特征及其细观表征方法，并建立了统计的二阶双尺度计算公式，讨论了材料的弹性极限强度准则.最后，针对不同的非一致随机分布复合材料，预测了材料的力学参数并与实验数据进行了对比.结果表明，统计的二阶双尺度方法对于预测非一致随机分布复合材料的力学参数是有效的.关键词：统计二阶双尺度方法非一致随机分布复合材料结构

Prediction on mechanical parameters of inconsistently random composites by statistical second-order two-scale method

The statistical second-order two-scale method is developed to predicte the mechanical parameters of the composite structure with inconsistently random distribution, including stiffness parameters and elastic limit strength parameters. This kind of structure, in which random inclusion dispersions are not the same everywhere but gradually changing in space, is called the structure with inconsistently random distribution. So, it possesses continuously varying macro-mechanical properties in space. In this paper, the microstructure of the composites with consistently/inconsistently random distributions is represented. The statistical second-order two-scale analysis formulation is established. And the strength criterion of the inconsistent random composite structure is discussed. Finally, the numerical results for different inconsistent composite structures are obtained and compared with the experiment data. Their agreement shows that the statistical second-order two-scale method is feasible to predict mechanical parameters of inconsistently random composites.