复合材料的安全系数统计分析

为了解决纤维增强树脂基复合材料(Fiber-reinforced plastics．FRP)结构设计中安全系数的取值问题,本文利用强度服从三参数Weibull分布。应力服从Gumbel分布时复合材料结构安全系数厂与可靠度之间的关系，对一些常用的FRP的安全系数与可靠度之间的关系进行了统计分析。给出了几种常用类型复合材料在不同应力变异系数和不同可靠度要求下的安全系数的统计取值范围。得到了应力变异系数为0．1,0.15和0.2时这些FRP的安全系数分散带。对于应力变异系数不等于0．1,0．15和0．2的情况，可以采用文中方法进行具体分析或进行插值计算。并得出了材料强度和应力的分散性对安全系数具有很大影响的结论。这对于复合材料结构设计有重要的参考价值。

Statistical Analysis on Safety Factor of Composite Materials

In order to find proper values of safety factor when des igning structures of fiber-reinforced plastics, the relationships between safet y factor and reliability of some fiber-reinforced plastics are statistically an alyzed. Based on the reliability model in which Gumbel distribution is used for the stress and Weibull distribution with three parameters for strength of compos ite materials. The scatter bound of safety factor of FRP is presented when the variation coefficient of the stress is 0 1, 0 15 or 0 2 and the reliability is 0 99 or 0 999 9. For other variation coefficients of the stress and the rel i ability, the safety factor can be derived by using the diagrams. And the safety factor has something to do with variation coefficients of the strength and the s tress. These data have an important reference value for the structure design of the composite material.