Rolf Dollevoet - Articles and news items
Issue 1 2012 / 6 February 2012 /
Since 2006, infra-manager ProRail has been keeping the Dutch rail free from Head Checks by grinding the rails in an Anti Head Check profile. Head Checks (HC) are rail defects that are created by wheel-rail contact. These can be serious safety threats. I obtained my doctorate in 2010 with the dissertation titled ‘Design of an Anti Head Check profile based on stress relief 1,2. I designed a rail profile that saves ProRail €50 million of maintenance costs for the rails per year. This rail profile made the volume of HC decrease by over 70% since late-2008. Head Checks are becoming extinct in the Netherlands.
In the Netherlands, approximately 70% of the total annual maintenance budget is spent on rails, including foundation, sleepers, ballast, constructions and switches3. Rails may seem to be simple elements, but they deserve ample attention. The wheel-rail contact is the force that brings the degeneration of both separate systems together. All failing mechanisms can eventually be brought down to this dynamic contact system. This also played a role in the serious and fatal UK rail accident in 2000 at Hatfield, where rails affected by HC broke down.
Shocked by this, infra-manager ProRail took a look at the situation in the Netherlands. Inspections proved that here HC was a serious problem as well: 10% of the curves (rails) appeared to have been affected. The safety, reliability and availability of the rails was in danger. The problem increased and expo – nentially grew each year. In the peak year 2004, ProRail spent €50 million on fighting HC.
Delft University of Technology has developed new technical regulation standards for the geometrical deviations of metallurgic rail welds in The Netherlands, in cooperation with the Dutch rail infrastructure manager ProRail.