The catenary system is the power source of high-speed trains and it contains critical components such as droppers and messenger wires. During train operation, the messenger wire vibrates in conjunction with the catenary. In order to obtain a more realistic vibration performance of the droppers, it is necessary to consider the vibration of the messenger wire. In this paper, the vibration equation of the messenger wire is firstly derived and solved, and the obtained solution is used as the boundary condition of the differential equation of the vibration of the dropper. By solving the differential equation of the dropper using the numerical method, the stress time diagrams of the dropper with and without considering the messenger wire are obtained. The results show that the maximum stresses of droppers I, II, III, IV, and V with the messenger wire are respectively 173, 154, 170, 222 and 164 MPa, however, those without the messenger wire exceed 300, 500, 400, 500 and 300 MPa. It can be seen that the maximum stress value of the dropper becomes lower after considering the effects of the messenger wire. It indicates that the messenger wire can attenuate the degree of vibration of the droppers, thus improving the overall vibration performance of the droppers.
He et al. (Fri,) studied this question.