复合材料的力学性能参数比金属材料呈现出更大的分散性。本文提出采用加权线性响应面法对复合材料单钉连接结构进行可靠性分析。采用三维有限元模型进行复合材料单钉连接的确定性渐进失效分析。单向铺层的力学性能参数和强度参数均考虑为输入随机变量,用于可靠性分析。详细研究了不同失效准则和不同刚度退化方法的影响。结果表明,Olmedo-Santiuste失效准则与Camanho-Matthews刚度退化方法的组合能够给出与试验均值最接近的强度分析结果。另外,还仔细研究了响应面参数f的影响。结果表明,取f=1的线性加权响应面能够为复合材料单钉连接可靠性分析提供较好的统计特性逼近值。
Composite materials exhibit much more scattering material properties than metallic materials.The paper presents an application of weighted response surface method on structural reliability analysis of a composite pin joint.A three-dimensional finite element model is used to perform the deterministic progressive failure analysis of composite pin joint.The mechanical properties and ultimate strengths of one lamina are modeled as random variables and considered in the process of structural reliability analysis.A detailed study on the effect of different failure criteria and stiffness degradation rules is performed.This study shows that the combination of Olmedo-Santiuste failure criteria and CamanhoMatthews stiffness degradation rules produces the closest bearing strength result to experimental mean value.Another detailed study is also performed to investigate the effect of response surface parameter f.The results show that linear weighted response surface function with f=1is capable of providing good approximations of statistical characteristics of the bearing strength of pin joints in composite laminates for structural reliability analysis.