Read how a VÖGELE paver lays ballast for railway track bed reliably and economically. A site report from Switzerland.

A Stony Task

A few modifications need to be made to the tractor unit and screed, but then SUPER pavers are capable of laying ballast for railway track bed with high reliability, the same reliability Swiss State Railways are famous for. This is a report on railbed construction for the express line between Bern and Zürich.

In a large project Swiss State Railways are currently carrying out new construction of a high-speed track between Bern and Zürich, the capitals of two Swiss cantons. The contract for railbed construction on a 40km section leading from Mattstetten to Rothrist, let by Zschokke Locher AG, was awarded to Swiss contractor Vanoli AG. For the double-track line, where after completion of the entire distance in the year 2005 Intercity trains will travel at speeds of more than 200km/h, the construction team built a railbed system made up of ballast, sleepers and rails including supply piping. For laying the ballast, a paver made by VÖGELE was on the scene.

Only minor modification needed to get a very special job done
For laying ballast only minor modification needs to be made to a VÖGELE paver. For the contract awarded to Vanoli, a SUPER 2000 with AB 575 Extending Screed in TV version was used. Rubber plates overlapping each other were fitted onto the feeder bars of the conveyor in order to fully cover up the conveyor’s floor. From the augers several blades had to be removed in order to better handle the spreading of ballast. A water spraying system with separate water tank was installed in the machine to prevent the raising of dust while laying the ballast. The screed was fitted in a position some 25cm higher than usual and further to the back. For grade and slope control a conventional automated system can be employed or a laser-based system, or laying can be done all without automatics at a fixed height. Together with the paver, a smooth drum roller was on the job site to bring about the final density.

	A SUPER 2000 modified for the laying of ballast.     The SUPER 2000 placed ballast in layers up to 55cm thick.

100 Freight trains loaded with ballast
The ballast for railbed construction came from the nearby Gotthardmassiv and was hauled over a distance of 80km by freight train to Langenthal, a village close to the building site. There 3 shuttle lorries took over and transported the ballast right to the paver. Contractor Vanoli, a company specialized in roadbed construction, laid a high-quality broken granite (32/64) for the track beds, each 420cm wide and 20cm to 55cm thick. On the 2 times 40km section the Swiss team placed a total of 170,000 tonnes of ballast, which is the loads of more than 100 freight trains. The SUPER 2000 paver reached a maximum operating speed of up to 50m per hour. As far as logistics are concerned only one road was available for the shuttle lorries to supply their loads, but even under these harder conditions it was no problem at all to achieve a daily laydown rate of some 1,200 tonnes. For producing the final density Vanoli had a 4t roller on site to further compact the ballast by another 3 to 4cm.

VÖGELE can take it
The results in terms of surface accuracy were very good. The accuracy achieved by the paver was higher compared with the one attainable by graders or similar construction machinery. The SUPER 2000 was a tough performer. Both tractor unit and screed got the stony task done with no signs of wear. It was the high-grade steel VÖGELE pavers are made of, that paid off here. The wearing parts, too, stood the test. The first set of sole plates on the AB 575 TV screed handled the 170,000 tonnes of ballast impeccably and can, no doubt, be used for further jobs.

Good results, high economic potential
Using a VÖGELE paver for laying ballast stands out through a high economic potential due to a low requirement for equipment and personnel. The paver operator manages the work with his machine on his own, so that with the roller operator just two men are on the building site. Contractor Vanoli is happy: “After a short time at the beginning when people needed to get familiar with their task, the SUPER 2000 did a great job with no problems at all”. VÖGELE pavers are capable of laying ballast very reliably, which makes them ideally suited to railbed construction projects – simply because of their high economic potential.