Study of longitudinal dynamics in the case of a train which does not have all the vehicles with active brake

The paper represents a small part of the studies conducted by the authors in the field of longitudinal dynamic phenomena developed in the body of the braked train. The aim of the study in this paper is to evaluate the effect of train composition on the maximum longitudinal forces magnitude and distribution along the train. The particular cases considered are those of trains that have vehicles running with isolated brake (i.e. not able to brake). For the simulations, a freight train consisting of 20 identical vehicles was originally used, followed by a classical train - locomotive and identical wagons, the total number of vehicles remaining the same. For each train formation, there are several scenarios regarding the positioning of the vehicles without brake in its body, scenarios that take into account the national regulations in force or the possible failures in service. A special case is represented by a possible failure of the locomotive braking system and the train movement under these conditions to a point where the problem can be remedied.