纤维增强复合材料层合板的模糊可靠度分析

纤维增强复合材料(FRP)的强度行为受组分材料、层合结构、载荷等多种因素的影响,且含有许多不确定因素,因此对FRP的可靠性分析十分重要,近年已有许多相关成果发表,但同时考虑随机性和模糊性的研究尚不多见。本文建立了复合材料模糊可靠度分析模型以及数值计算方法模型,通过算例分析了复合材料层合板受面内拉伸载荷作用时的模糊可靠度。将载荷作为随机变量,强度作为模糊变量,并采用蒙特卡罗数值模拟方法,对层合板结构的可靠度进行了计算。分析中采用最大应力准则计算了单元层的破坏概率,然后利用首层失效准则计算了层合板的可靠度。通过对算例的分析和与其他结果的对比,讨论了本文方法的有效性,以及参数敏感性。

Fuzzy Reliability of Fiber Reinforced Composite Laminate

The performances of constitutive materials, laminate structures, material components and load conditions etc., can greatly influene the strength behaviors of the Fiber Reinforced Plastics (FRP) composites, accompanying many uncertain factors. The previous researches scarecely considered both the random and fuzzy variables in the reliability analysis. A fuzzy reliability model for FRP laminates is established where the loads are taken as the random variables and the strengths as fuzzy variables. And a numerical model is developed to calculate the fuzzy reliability of a laminate. Monte Carlo simulation method is utilized to compute the reliability of laminas combined with the maximal stress criterion. The system reliability is evaluated based on the first-ply failure criterion, which illustrates the validity and efficciency of the proposed method.