含缺陷圆轴结构极限承载规律研究

目的 研究车辆传动轴在受损情况下极限承载能力的变化规律。方法 在圆轴上预制缺陷，并对含缺陷圆轴结构承受扭转载荷的能力进行试验和数值模拟研究。结果 当圆孔缺陷深径比保持不变时，圆轴极限扭矩下降比随圆孔缺陷孔径比的增加而减小；当圆孔缺陷孔径比保持不变时，圆轴极限扭矩下降比随圆孔缺陷深径比的增加而减小。当深径比大于0.4时，圆轴极限扭矩下降比与圆孔缺陷孔径比近似呈负线性相关。当缺陷孔径比大于0.4、深径比大于0.2时，圆轴最大扭角减小为15°~35°，各存在缺陷的圆轴的最大扭角差距不大。结论 圆轴扭转失效时，其最大扭角、极限扭矩与圆孔缺陷孔径比、深径比整体均呈负相关趋势。在孔径比和深径比逐渐增大的过程中，极限扭矩呈近似线性关系逐渐降低，而最大扭角先急剧减小，后逐渐趋于平稳。

Ultimate Bearing Law of Circular Shaft Structure with Defect

The work aims to study the change rule of ultimate bearing capacity of damaged vehicle drive shafts. The defects were prefabricated on a circular shaft and the torsional load bearing capacity of the circular shaft structure with defects was investigated experimentally and numerically. The results showed that when the depth-diameter ratio of the circular hole defect remained unchanged, the decreasing ratio of ultimate torque of the circular shaft decreased with the increase of circular hole defect aperture ratio. The decreasing ratio of the ultimate torque of the circular shaft decreased with the increase of the depth-diameter ratio of the circular hole defect when the aperture ratio of the circular hole defect remained unchanged. When the depth-diameter ratio was greater than 0.4, the decreasing ratio of the ultimate torque of the circular shaft was approximately negatively linear correlated with the aperture ratio of the circular hole defect. When the defect aperture ratio was greater than 0.4 and the depth-diameter ratio was greater than 0.2, the maximum torsion angle of the circular shaft decreased to between 15° and 35°, and there was little difference in the maximum torsion angle between the circular shaft with defects. When torsional failure occurs, the maximum torsion angle and ultimate torque of the circular shaft are negatively correlated with the aperture ratio and the depth-diameter ratio of the circular hole defect. In the process of increasing aperture ratio and depth-diameter ratio, the limiting torque decreases gradually in an approximate linear relationship, while the maximum torsion angle decreases sharply at first and then gradually becomes stable.