基于二阶矩法的薄壁柱壳的可靠性设计

RELIABLITY DESIGN OF THIN WALLED CYLINDER SHELLS BASED ON THE SECOND MOMENT METHOD

将二阶矩法应用于内压圆柱形壳体的可靠性设计,根据弹性失效设计准的第一强度理论可定义三个功能函数,基于不同的功能函数推导出各自的可靠性指标。以某压力容器设计为例,计算出不同径比下的三种不同方法可靠性设计厚度。结果表明,当径比较小时,利用不同的功能函数得出的计算厚度几乎无差异,随着径比的增加结果的差异增加。

The second moment method was applied to the reliability design of thin walled cylindrical shells with internal pressure.Three functions were defined according to The First Strength Theory of elastic failure.The reliability indexs were respectively worked out based on different performance functions.Then by using above—mentioned ways the thickness of thin walled cylindrical shells with different diameter ratio was calculated.The result showed that differences of thickness with thin walled cylindrical shells calculated by using different performance functions is small when diameter is relatively small.However with increasing of diameter ratio differences of the thickness is increased accordingly.