Abstract: The fatigue load of steel liner in headrace tunnel of a pumped storage power plant during operation is calculated based on nominal stress, the cycle number of fatigue load is counted by use of reservoir method recommended by EN standard and the fatigue strength of the butt weld is determined according to a proper fatigue curve. Moreover, the fatigue of steel liner butt weld is assessed based on Palmgren-Miner theory of linear cumulative damage theory. The assessment result shows that the weld fatigue life meets owner's requirement and the design approach provides a reference for fatigue analysis of steel liner of similar projects.

Key words: nominal stress, butt weld, fatigue analysis, S-N curve, cycle counting, reservoir method, cumulative damage

摘要：

基于名义应力计算了某抽水蓄能电站引水隧洞钢衬运行期间疲劳荷载，采用欧盟标准的蓄水池循环计数方法统计了疲劳荷载循环次数，并根据焊缝类型选取合适的疲劳曲线确定焊缝疲劳强度，最后基于线性累计损伤理论中的“Palmgren-Miner”理论对钢衬对接焊缝进行疲劳评估。计算结果表明，焊缝疲劳寿命满足业主要求，可为类似水电工程钢衬疲劳分析提供参考。

关键词: 名义应力, 对接焊缝, 疲劳分析, S-N曲线, 循环计数, 蓄水池法, 累计损伤