Pioneering the Application of High Speed Rail Express Trainsets in ...

The energy absorbers work in two stages, the anti-climber absorbers and the main crush
box. Both are fabricated from steel sheets approximately 0.25 inch (6,4 mm) thick with yield
strength of approximately 46.4 ksi (320 MPa). The two anti-climber absorbers, one on each
side to line up with European buffers (elements installed at each corner of the end of a rail
vehicle), are bolted to and protrude from the crush box. They are approximately 13.8 inches
(350 mm) in length. The absorbers are tapered and have ribs on their outboard faces except
for an approximately 2-inch (50-mm)-long straight section on the outboard end of the absorber
that helps to control collapse during the crush process.
The Velaro crush box consists of several flat plates welded together in a rectilinear fashion
to form several large cells, two deep in the longitudinal direction. Some local reinforcement is
used to facilitate collapse during crush. The crush box bolts directly onto the carbody. There
is an additional plate on the inboard side of the crush box. The thickness/strength of this plate
will not quite satisfy the CFR requirement (per 49 CFR §238.409 Section (d)), although a slight
increase in thickness could be made. Siemens believes there is no need to modify the current
crush box design, however, and that the steel it is made of is adequate. Siemens advised
that some minor cracking of the absorbers occurs on crush, but that it does not affect performance.
The longitudinal welds were placed to minimize cracking.
Siemens advised that as a result of the large surface of the CEM module on the Velaro,
crash energy absorption is possible even with offset collisions. There is no explicit crushable
structure at the coupled intercar ends of a Velaro trainset. The outer “skin” of the aluminum
profile extends beyond the car ends at the coupled interface and would absorb some energy
on crush. The ends themselves would also crush eventually. Siemens does not include the
composite mask in crush calculations. It believes that these masks do not interfere with the
crush zone operation. This view is supported by calculations and tests done on light rail vehicles
in which the mask was included.
Siemens advised that dynamic crush testing for the lead end crushable structure of the Velaro
(i.e., standard crash module) was conducted at Tuev-Sued (Technischer Ueberwachungs
Verein) in Gorlitz, Germany. Only one dynamic test was conducted. This test did not provide
the performance Siemens desired, so Siemens refined its model and material properties until
agreement between the simulation and test observations was reached. Subsequent refinement
of the crushable structure design was then performed through simulation.
3.3 PASSIVE SAFETY
3.3.1 Trainset Design
Manufacturers of HSR trainsets for Europe have incorporated passive safety elements into
the structural design to reduce the consequences of an accident should it occur. Alstom provided
insight into the incorporation of passive safety into current HSR trainset designs.
3.3.1.1 Alstom
Alstom advised that train systems must be secure from the perspectives of active safety—
the prevention of accidents, and passive safety—the mitigation of consequences in the event
of accidents. Active safety can be achieved through, for example, train control systems,
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