不同强度分析中各种载荷的叠加原则——压力容器应力分析设计中的六个重要问题(二)

THE SUPERPOSITION PRINCIPLE OF COMBINED LOADS IN STRENGTH ANALYSIS——SIX IMPORTANT ISSUES ABOUT DESIGN IN STRESS ANALYSIS FOR PRESSURE VESSELS(PART 2)

压力容器的各种载荷可分别引起一次应力、二次应力和峰值应力,根据三种应力的失效机理,讨论了压力载荷、重力载荷、风载荷和地震载荷分别引起的三种应力的叠加原则,指出:这些载荷引起的一次应力应同时叠加;压力载荷、重力载荷产生的二次应力和风载荷、地震载荷产生的二次应力应分别满足安定条件,而不是同时叠加;峰值应力应以损伤叠加—累积损伤进行评定。

The different loads in pressure vessels may lead to primary stress,secondary stress and peak stress.According to the failure modes of these three kinds of stress,this paper discusses the superposition principle of these stresses caused by pressure,gravity,wind and earthquake.And it points out that the primary stresses caused by combined loads shall be added together;secondary stresses caused by pressure,gravity,wind and earthquake shall not be added together;they shall meet the stability principle separately;peak stresses shall be added together according to cumulative damage.