Analysis of dynamic stress characteristics of suspension frame of medium and low-speed maglev train

Abstract As an important bearing part of maglev trains, the suspension frame of medium and low-speed maglev trains often suffers fatigue damage, which leads to a serious lack of fatigue reliability. Therefore, it is urgent to research the dynamic stress characteristics of the suspension frame. To assess whether the suspension frame of a medium-and low-speed maglev train satisfies the required strength criteria, a comprehensive line test was conducted to evaluate its fatigue strength. Building on these results, the dynamic stress characteristics of the suspension frame under varying operating conditions were analyzed. This investigation focused on identifying the primary frequency sources of dynamic stress, as well as examining the effects of speed variations and different operational scenarios on the dynamic stress behavior of the suspension frame. The results show that the equivalent stress amplitude of each measuring point of the suspension frame will increase with the speed grade, and the most obvious one is the lower bracket area, which increases by 52%.