(1 中冶集团建筑研究总院 北京 100088；2 宝山钢铁股份有限公司设备部 上海 201900)
［提要］某依附于平台框架的分离式柱承受最大为450/80t重级工作制吊车荷载的作用，建成使用不到20年，有多根柱子在柱头处出现裂缝。现场应力测量和结构整体的计算分析表明，由于构造不合理，裂缝处存在较高的压应力和初始拉应力。在吊车荷载反复作用下，疲劳强度不足，因而出现疲劳破坏。考虑到出现裂缝后，初始应力会得到一定程度的释放，提出了简单的局部加固方案，并付诸实施。
［关键词］ 分离式柱 疲劳 吊车荷载 应力测量 加固
Fatigue Failure of Separate Steel Columns in a Working Platform Frame/Yang Jianping１，Chang Haosong1,Xing Kuntao1,Tong Xiaoli1,Cheng Haibo2,Wang Fa 2,Zhou Youhuai 2
(1 National Diagnosis and Rehabilitation of Industrial Building Research Center,Beijing 100088,China; 2 Equipment Department,Baoshan Iron & Steel Co.，Ltd.,Shanghai 201900,China)
Abstract:Separate columns braced by working platform frame are subjected to loading of heavy working cranes up to 450/80t. Within  20 years since they were built up, cracks were found at the top of the columns. Stress measurement and structure analyses show that there were high compression stress and initial tension stress at the the top of the columns because of inappropriate construction design. Under the repeated loading of the cranes, the fatigue strength of the columns is insufficient, and fatigue failures occurred. Considering that the initial stress could be released with the cracks initiation, a local  strengthening measure is presented and it has been executed.
Keywords:separate column； fatigue； crane loading； stress measurement； strengthening