摘要
针对钢吊车梁中普遍存在的支座附近产生裂缝的破坏现象,选取建于20世纪70年代的某炼钢厂房吊车梁为研究对象,模拟吊车在吊车梁上的行走过程,并分析吊车梁的应力分布规律和应力-时间历程。通过雨流计数法处理吊车梁上最危险点的应力循环,获得吊车梁的疲劳应力谱,并采用6种现有的疲劳寿命预测方法对吊车梁进行疲劳寿命预测。结果表明:相同板件尺寸条件下,选用直角突变型支座形式的吊车梁的疲劳寿命预测值要比其他支座形式的高,而梯形过渡式次之,角钢封板式和圆弧过渡式钢吊车梁的疲劳性能较差。支座加劲肋能够有效减小支座处的等效应力,提高其疲劳寿命。当支座端的腹板上下两部分高度相对一致时,吊车梁的疲劳性能相对较优。
In view of the cracks near the supports commonly encountered in steel crane beams,the steel crane runway girder built in the 1970s was selected as the research object.By simulating the working process of the crane on the crane beam,th stress distribution and stress time-history of crane girder was analyzed.The stress cycle of the most dangerous point on the crane girder was dealt with rain flow counting method,and the fatigue stress spectrum was obtained.Six existing fatigue life prediction methods were used to predict the fatigue life of crane girders.The results showed that,under the same plate size condition,the fatigue life prediction value of crane girder with rectangular mutational support was higher than that of other support forms,and the fatigue performance of trapezoidal transition type was next,angle steel seal plate type and arc transition type steel crane girder were worse.The stiffening ribs could effectively reduce the equivalent stress at the bearing and improve its fatigue life.The fatigue performance of crane girder was relatively better when the heights of the upper and lower parts of the web at the support were relatively uniform.
作者
杨佑发
任浩亮
凌昊
YANG Youfa;REN Haoliang;LING Hao(College of Civil Engineering,Chongqing University,Chongqing 400045,China;China Railway First Survey&Design Institute Group Co.,Ltd.,Xi’an 710043,China)
出处
《钢结构》
2019年第6期36-43,共8页
Steel Construction
基金
重庆市建设科技计划项目(2016-07)
关键词
钢吊车梁
疲劳寿命
累积损伤
DFR法
直角突变型支座
steel crane runway girder
fatigue life
damage cumulation
DFR method
rectangular mutational support
