Joseph Voegele AG - Technologies - Applications Technology

Turkey invests into a new, modern railway line linking Istanbul with Ankara. 110km of the ballast track bed totalling a length of 510km are laid by a modified VÖGELE road paver type SUPER 1900. For grade control, a Laser Receiver is used which eliminates the need for a tensioned wire.

The new rail route linking Istanbul with Ankara extends over 510km.

In order to withstand wear, feeder bars of the conveyors are provided with rubber baffles.

The track bed requires laying of 500,000 tonnes of basalt ballast (stone size 30–60mm).

Construction of 110km section for new railway route linking Istanbul with Ankara

Expected time to complete: 6 months

Equipment

Modified VÖGELE SUPER 1900 with SB 250 Fixed-Width Screed in TV Version

Job Site Details

Operating speed: 2.5–3m/min.

Thickness of ballast layer: 30–50cm

Track Bed

laid in 2 strips each 4.5m wide

Quantity of Ballast Laid

3,000 t a day

Material

500.000 t of basalt ballast (stone size 30/60)

New construction of a 510km long high-speed rail route leading from Istanbul to Ankara is one of several ambitious projects Turkey currently undertakes to modernize the country’s rail network. After completion, high speed trains capable of going some 250km/h will cut travel time for passengers between the two big cities considerably, then taking no more than about 3 hours.

A 110km stretch

The contract for construction of a 210km section of the double-track route was awarded to the Joint Venture between Turkish contractor Alarko (Istanbul) and the Spanish enterprise OHL (Madrid). TUR Insaat Co. has a sub-contract let by OHL for building a 110km stretch of the above section. For the track bed alone, 500,000 tonnes of ballast have to be laid, a challenge to logistics and machinery alike.

TUR Insaat Co. relied on VÖGELE’s long experience in the laying of railway ballast with road pavers and opted for a SUPER 1900. In order not to expose the paver to the risk of damaging by the abrasive nature of the coarse basalt ballast with a stone size of 30 – 60mm, VÖGELE prepared the paver for the hard job by appropriate modification. For optimal conveyance of the ballast, twice the number of feeder bars was fitted to the conveyors and each feeder bar provided with a screw-fit rubber baffle. VÖGELE reinforced their paver in many other places, too: the conveyor tunnel was lined with plates of highly wear-resistant Hardox steel and auger bearing boxes as well as augers provided with guards to withstand wear. In order to meet the special requirements of ballast laying, a modified auger system was installed with an auger blade diameter of 300mm. Also the tamper of the SB 250 Fixed-Width Screed in TV version is of a design sturdier than the one equipped as standard.

As basalt ballast has to be placed in thick layers, a larger range needs to be available for height adjustment of the screed compared to conventional pavers. This is why this special paver comes with steel plates flanged at the interfaces between screed and tractor unit. As a result, the SB 250 Fixed-Width Screed can be set up to a maximum layer thickness of 55cm. Given the trapezoidal geometry of the track bed, the screed is fitted with a bevel iron (18cm long) bevelling the ballast, while laying, at an angle of 45°. In addition, the screed features a tongue-shaped plate fitted right in the middle, serving to press the ballast down some 40mm in the mid-area of the track bed over a width of 800mm. This is to ensure that a sturdy seat is created to accomodate the sleepers, thus preventing them from wobbling when under load. The seats enhance stability of the concrete sleepers laid directly onto the ballast and eliminate the risk of sleepers breaking as trains travel on the track system.

After the paver had been optimally prepared for the job, construction of the first section began early in March 2006 and is currently underway. On a sub-base, 14m wide, and a 12m wide crushed-stone base, the SUPER 1900 places ballast in 2 passes, each 4.5m wide, for the track bed which tapers to 9m width towards the top. Ballast is placed in an average thickness of 30cm, on straight and curved sections alike, and the paver operates at a speed of 2.5m to 3m/min.

For grade control, the construction team could be convinced of the advantages offered by a Laser Receiver. The Laser Receiver is ideally suited to projects on which large distances are paved with unchanged elevation of the screed. After a trial, it was primarily the Laser Receiver’s easy handling and the high cost-effectiveness that were absolutely convincing and accepted as strong arguments in favour of its use.

The SUPER 1900 creates perfect seats for the concrete sleepers by pressing the ballast 40mm down in the mid-area over a width of 800mm.

Thanks to a larger range for height adjustment of the screed, the modified SUPER 1900 is capable of placing layers up to 55cm thick.

For optimal spreading of the ballast, auger blade diameter is reduced to 300mm.

The rotating beam emitted by the laser unit creates a plane picked up by the Laser Receiver. Should the Laser Receiver installed on the machine move above or below the laser plane, signals for correction are emitted to VÖGELE NIVELTRONIC®, the System for Automated Grade and Slope Control.

The system for non-contacting grade and slope control offered by VÖGELE stands out through easy handling. When connected to VÖGELE NIVELTRONIC®, the Laser Receiver is recognized automatically

as a grade sensor and ready for use immediately.

The VÖGELE Laser Receiver is ideal, above all, for surfacing large areas lying in a plane such as sports stadiums, parking lots or storage areas or, as in this case, for construction of a traffic route over a long distance. Fitting the Laser Receiver at a height of up to 4.5m guarantees uninterrupted operation even with job site vehicles passing.