CSM玻璃钢复合型断裂的有限元分析

对切短玻璃纤维毡增强聚脂层板的复合型断裂进行了有限元分析。采用八节点四边形等参元的正规型式计算应力分布与损伤区扩展;而用坍塌(collapsed)三角形四分之一点(quarter-point)奇异元计算应力强度因子K_Ⅰ与K_Ⅱ。用节点位移约束与释放技术计算了裂纹扩展过程。对决定应力强度因子K_Ⅰ与K_Ⅱ的三种方法进行了对比。对施加于裂纹顶点节点约束条件的影响进行了评价。最后基于实验测得的断裂载荷与临界裂纹长度,估算了材料在这种受力条件下的复合型临界应力强度因子K_ⅠC和K_ⅡC。

FEM Analysis on Mixed-Mode Fracture of CSM-GRP

An FEM analysis for studying mized-mode fracture problem of chopped strand mat glass fibre reinforced polyester laminate was presented, The analysis was formulated on the basis of 8-node quadrilateral isoparametric element, The collapsed triangular quarter-point singular elements were used for calculating stress intensity factors K_Ⅰ and K_Ⅱ. The crank propagation process was computed by implementing constraint release technique, Three different approaches to the solution of stress intensity factors K_Ⅰ and K_Ⅱ were compared, The effect of constraint condition imposed upon the displacement of the three collapsed nodes of the crack tip elements on the K_Ⅰ and K_Ⅱ results was evaluated, The mixed-mode critical stiress intensity factors K_ⅠC and K_ⅡC were estimated for CSM-GRP through the consideration of K_Ⅰ and K_Ⅱ calculated and the measured failure load and critical crack length in the experiment.