基于累积损伤的减振器座梁寿命分析

Life Analysis of Vibration Damper Beam Based on Accumulation Damage

针对某型动力车横向减振器座梁振动载荷下应力过大的问题,开展了试验测试和数值模拟。通过应变片测量得到减振器座梁的线路载荷谱。基于试验测量的线路载荷谱,结合铁路标准,提出了2种疲劳评估方法。第1种疲劳评估方法是针对不同载荷工况间的(σ~σ)确定疲劳应力变化范围,进行疲劳评估,适用于结构设计阶段。第2种疲劳评估方法是基于测量的线路载荷谱,对该型横向减振器座梁进行累积损伤计算,得到全寿命服役损伤和疲劳寿命,适用于线路运行阶段的疲劳校核。计算结果表明:16级载荷下,线路载荷谱中4~11级载荷贡献了超过90%的损伤量,是减振器座梁设计中需要重点考虑的载荷项。采用2种疲劳评估方法,对实测方案中车体减振器座进行改进,经过重新优化修改后的设计方案满足线路900万km的运营要求。

Experimental and numerical methods were used to solve the excessive high stress in the vibration of the beam of vibration damper in power concentrated EMU.The strain gauge was used for the measurement of the railway load spectrum.Based on the measured railway load spectrum,two fatigue evaluation methods were proposed in combination with the railway standards.In the first fatigue evaluation method(σ-σ)was used for the determination of the fatigue stress amplitude,which is suitable for the design stage.In the second fatigue evaluation method,the cumulative damage can be calculated to obtain the fatigue life of the vibration damper beam to obtain the service life damage and the fatigue life,which is suitable for the fatigue evaluation in the operational stage.Results indicate that the 4th-11th of the total 16 load classes can contribute more than 90%cumulative damage and should be the most important factor in the design.Based on the proposed two fatigue evaluation methods,the design of the vibration damper beam was improved and the revised design meets operational requirements of 9 million kilometers.