“…The equated load-bearing frame of a locomotive of complex configuration is modeled by an elastic rod of variable cross-section with variable mass, bending and extension stiffness. The difference of the proposed model from the existing ones [9,10,13] is that it takes into account the variability of cross-section, mass, bending and extension strength along the length of the equivalent beam, which complies with the real operating conditions. In existing calculation methods, for simplicity, it is assumed that the beam is of equal resistance or an approximate calculation is performed using a model with concentrated parameters without taking elasticity into account.…”