Analysis of dynamic loads on the cars of a high-speed motor-car train with a passive safety system in its collision with a freight car

Abstract

The performance characteristics of the cars of a modern home high-speed motor-car train must meet Ukrainian State Standards DSTU EN 12663 and DSTU EN 15227 now in force in Ukraine, which regulate its crashworthiness and passive safety in emergency collisions. An integral part of new cars must be passive safety systems (PSSs) with energy-absorbing devices (EADs), which save the lives of the pasengers and the train crew and reduce car damage in a collision with an obstacle. The aim of this paper is to evaluate dynamic loads on the cars of PSS-equipeed motor-car train in its collision with a freight car according to Scenario 2 of DSTU EN 15227. The scientific novelty of the paper is a mathematical model for the study of a collision of a motor-car train with a freight car based on the authors’ model of a collision of identical motor-car trains (Scenario 1 of DSTU EN 15227) with account for the force characteristic of head car – freight car interaction in an emergency. The proposed mathematical model allows one to obtain the average values of the car accelerations and plastic deformations to compare them with their admissible values according to DSTU EN 15227. The paper presents the results of a study of dynamic loads on the cars of a PSS-equipped motor-car train in its collision at 36 km/h with a 80 t freight car for a reference train with a 80 head car and four intermediate cars of mass 50 t, which is the mass of the majority of cars on the 1,435 mm European railways, and 64 t, which is the typical mass of inremediate cars used in the 1,520 mm Ukrainian railways. The following protective devices developed at the Institute of Technical mechanics of the National Academy of Sciences of Ukraine and the State Space Agenccy of Ukraine are proposed for passive protection: EAD 1 devices of energy capacity 0.95 MJ to be mounted at the coupler level at the head car front end, EAD 2 devices of energy capacity 0.25 MJ and EAD 3 devices of energy capacity 0.3 MJ to be mouned at the coupler level at the head car rear end and at the ends of passenger cars of mass 50 t and 64 t, respectively, and EAD UL upper-level energy-absorbing devices of energy capacity of 0.12 MJ to be mounted at the head car front end under the window. It is shown that by the criteria of DSTU EN 15227 for a train with 50 t intermediate cars it is advisable to use the passive protection according to Scenario 1 (the front end of the head car is equipped wuth two EAD 1 and two EAD UL devices, its rear end is equipped with two EAD 2 devices, and the intermediate cars are equipeed with two EAD 2 devices at the front and at the rear), while for a train with 64 t intermediate cars it is advisable to use the passive protection according to Scebario 2 (the front end of the head car is equipped wuth two EAD 1 and two EAD UL devices, its rear end is equipped with two EAD 3 devices, and the intermediate cars are equipeed with two EAD 3 devices at the front and at the rear). The proposed mathematical model and the results obtained may be used in designing head and intermediate cars for a home motor-car passenger train in accordance with the DSTU EN 15227 requirements.