转向架外侧定位抗侧滚扭杆结构强度评估方法

Evaluation Method of Bogie Outer Positioning Anti-rolling Torsion Bar Structural Strength

[目的]为了对轨道交通列车外侧支撑抗侧滚装置扭杆轴的扭转刚度和扭杆轴强度进行求解,提出一种引入变形协调条件的扭杆轴解析分析方法。[方法]以外侧支撑抗侧滚扭杆装置的1/2扭杆轴为例,根据其受力状态和载荷分布,利用结构的对称性及承担反对称工作载荷的特点,引入结构变形协调条件,求解一次超静定系统的未知力和力矩,获得扭杆轴的剪力和弯矩分布,并推导出抗侧滚扭杆装置扭转刚度和强度的计算公式。以52CrMoV4弹簧钢制造的外侧支撑抗侧滚扭杆装置为例,对比分析了外侧支撑扭杆轴的解析解法计算结果和有限元模型的计算结果。[结果及结论]所提解析解法能够较为便捷地确定扭杆轴不同截面位置的工作应力水平和应力状态,为确定扭杆轴的截面几何参数、不同危险截面的等效应力计算方法和扭杆轴的疲劳失效机理分析提供了理论基础。与有限元法相比,所提解析法具有计算原理简单、计算速度快等优点。

[Objective]In order to solve the TBS(torsion bar shaft)torsional stiffness and strength for the outer support anti-rolling device in railway vehicles,an analytical method of introducing the TBS deformation coordination conditions is proposed.[Method]Taking 1/2 TBS for the outer support anti-rolling device as an example,based on its stress state and load distribution,the structural symmetry and the characteristics of bearing anti-symmetric working loads are used to introduce structural deformation coordination conditions for solving the unknown forces and moments of a primary statically indeterminate system,obtaining the shear force and bending moment distribution of the TBS,and deriving calculation formulas for the torsional stiffness and strength of the anti-rolling torsion bar device.Using the outer support anti-rolling torsion bar device made of 52CrMoV4 spring steel as an example,a comparative analysis is conducted between the analytical solution calculation results and the finite element model calculation results of the outer support TBS.[Result&Conclusion]The proposed analytical solution method can conveniently determine the stress levels and stress states at different TBS cross-sectional positions,providing a theoretical basis for determining the TBS cross-sectional geometric parameters,the equivalent stress calculation method of different critical cross-sections,and the analysis of TBS fatigue failure mechanism.Compared with the finite element method,the proposed analytical method features simple calculation principle and fast calculation speed.