Division 4.1.7 Mechanical boundary characteristics for rolling stock (BP15)

The static and dynamic strength of vehicle bodies shall ensure the safety required for passengers and train crew. In particular, it should cope in the event of a collision with objects from outside of the rail system, such as heavy lorries or rock falls.

The construction standards used for this purpose shall ensure what is called passive safety. They do not compensate for a possible lack of active safety in the railway network but shall complement personal safety in unforeseen events that are beyond the control of the railway system.

The mechanical boundary limits defined for rolling stock to ensure that this requirement is met are defined below:

1. (a)

   static resistance of vehicle structures, and

2. (b)

   passive safety (crashworthiness).

1. (a)

   Static resistance of vehicle bodyshells

   1. (a1)

      Vertical static resistance:

      The bodyshell of each vehicle shall be able to withstand, without permanent deformation, the vertical static proof loads Fz in the following configurations:

      • jacking of the complete body of the vehicle in running order (VRO), without the running gear, by its four jacking points,

      • lifting of one end of the body, VRO,

      • exceptional vertical load:

        the greater of the two values of Fz = 1,3 (m₁ + (m₂₁ or m₂₂)) × g (N) where

        m₁

      • weight of the car body, VRO, with tanks assumed to be half full,

      m₂₁

      • number of seats (excluding tip-ups) × 2 × 80 kg,

      m₂₂

      • number of seats (excluding tip-ups) × 80 kg + area of corridors and vestibules (m²) × 4 × 80 kg.

   2. (a2)

      Longitudinal static resistance:

      • The bodyshell of each vehicle shall be able to withstand a static longitudinal, compressive loading, at the level of the coupler attachments, of at least 1 500 kN without residual deformation.

        Note:

        If this value is lower than the longitudinal resistance specified by the passive safety criteria, then the passive safety criteria value shall be applied.

2. (b)

   Passive safety (crashworthiness)

   See Annex A for a detailed explanation of these characteristics.

   In the event of a frontal impact, the mechanical structure of vehicles shall:

   • resist over-riding,

   • limit deceleration,

   • protect the areas occupied by passengers and the driver as far as possible,

   • absorb the energy collision.

   Three collision scenarios are proposed; corresponding respectively to:

   • a front end impact between two trainsets,

   • a front end impact with a vehicle fitted with side buffers,

   • an impact with a lorry on a level crossing.

   Main specifications to be met:

   • limited deformation to the driver and passenger areas from a static resistance with the ability to withstand a mean crush load of 1 500 kN,

   • dissipation of 6 MJ of crash energy of which at least 4,5 MJ shall be in the front part of the first vehicle,

   • all the vehicles in the trainset shall have a consistent level of crashworthiness

   • a maximum average deceleration in passenger and drivers cab areas to 5 g,

   • the vehicle ends shall be fitted with devices preventing over-riding.

   The problems, principles, scenarios as well as the specifications to be met for crashworthiness are described in more detail in Annex A.

   Assessment shall be made during the design phase and the integration of components and subassemblies; it shall include the assessment of material properties by crash tests on mock-ups or prototypes. Crush tests can be used as an alternative to assess conformity if the results can be accurately correlated with those of crash tests. Validation of technical solutions related to the present paragraph shall be made according to EN 12663 standard.

   Trains must withstand the mechanical loads due to pressure variations in tunnels.