损伤对复合材料层板层间裂纹奇异性的影响

基于连续损伤理论,采用非线性多标量连续损伤模型和有限元法对含Ⅰ型裂纹的纤维增强复合材料层板的裂尖应力奇异性进行了分析·在计算中,应用了损伤与位移同时迭代的全耦合法,并考虑了几何非线性的影响·结果表明:有限元法分析含损伤裂尖应力场奇异性是有效的;在材料硬化阶段,含层间裂纹的层板裂尖前缘应力奇异性总是存在的;损伤演化、材料常数影响裂尖应力奇异性,当材料常数的变化使损伤增大时,将导致应力奇异性程度下降·

Effect of Damage on Interlaminar Crack Singularity of Composite Laminae

Based on continuous damage theory, the crack-tip stress singularity of composite fiber-reinforced resin laminae with a Mode I crack was analyzed by finite element method and a nonlinear and multi-scalar damage model. Considering the geometrical non-linearity, a full coupling method iterating the damage and displacement simultaneously is applied to computation. The numerical results indicate that FEM is efficient to analyze stress singularity, and the stress singularity always exists in the hardening phase of material and decreases with the damage increment in crack tip. The relationships between singularity and material properties are presented.