JOB REPORT

Precision work in the darkness of night.

Paving a slab track for Madrid’s railway network

More than half a million people travel on the local trains of Madrid’s “Cercanía” line every day, commuting between the main stations of Chamartín in the north and Atocha in Madrid’s city centre. Increasing numbers of passengers had led to capacity and safety problems, making the expansion of Madrid’s major traffic artery a “must”. The city fathers planned to install two new railway lines on the 8.2 km long section connecting Atocha and Chamartín.

On the 5 km long leg between Atocha and “Nuevos Ministerios” station, the new track bed was to be built as a slab track. The contractors relied on the well-proven technology of the SP 500 slipform paver from Wirtgen to perform this job. As space was extremely limited, levelling was effected via a wireless control system using total station and prism instead of scanning along a stringline. Leica Geosystems – one of Wirtgen’s system partners – had taken on the job of transferring the digital information from the plans to the SP 500’s control system, which enabled the concrete sections to be paved with pin-point accuracy.

In as many as 30 night shifts, the SP 500 slipform paver from Wirtgen paved the slab track in two separate sections of 3.35 m width each and at a thickness of up to 45 cm. The monolithic profile grew in length by some 170 m each night, using 550 m³ of concrete, before the tracks could be laid. The site engineers of the Spanish joint venture companies were fully satisfied with the work results, “The SP 500 from Wirtgen has fully rewarded us for the trust we put in its performance and reliability right from the start.”