【摘要】 基于现场实测风机桥架振动响应,采用风机调幅扰力模型进行结构动力响应分析。根据不同工况下疲劳危险点的名义应力时程,采用雨流计数法和各工况年运行频次调查结果编制疲劳载荷谱。通过Miner损伤累积准则和p-S-N关系对风机桥架进行疲劳损伤分析,给定疲劳破坏的损伤阈值,所得疲劳寿命满足设计使用年限的要求。采用Goodman、Gerber和Soderberg模型考虑平均应力影响时的疲劳寿命略有降低。更多还原

【Abstract】 Based on the in-situ tested vibration responses of an air-cooling fan bridge,the dynamic analysis is performed with modulation amplitude disturbing force model of draught fans.Rainflow method is used to count stress cycles and the fatigue load spectrum of air-cooling fan bridges is then programmed combined with investigation results of running frequencies of different operation modes per year.Fatigue damage to the air-cooling fan bridge is calculated in terms of Miner’s cumulative damage rule and design p-S-N curve.After giving the damage threshold corresponding to fatigue failure,the predicted fatigue life of the fan bridge is longer than the designed service life.Furthermore,the fatigue life slightly decreases as effects of mean stress are taken into consideration by Goodman’s,Gerber’s and Soderberg’s models.更多还原