Turning out old train bridges

Hydraulics, wire sawing and DURAMANT®'s strong performance in Salzburg

In Salzburg, the expansion and optimisation of the route of lines of the S-Bahn (urban railway) have been in progress for the last years. To finalise the works, the last, remaining narrow point had to be extended. Around the central railway station, the old railway bridges were torn down and instead, new ones were buildt. The bridge over the Rainerstraße with its five lines were the first one as it was too weak for the upcoming stress and load by the new S-Bahn and the high performance railway line to Munich.

The challenge was to keep the trains going that were heading for Germany / Western Austria during construction works, so a part of the bridge had to remain: Two lines had to be trafficable. The works concept scheduled to build one half in 2009 and the other one in 2010.

The first part was kicked off in March 2009. To remove two lines and the subjacent bridge construction, they had to be separated from the other half. As it was a concrete-lined beam bridge, diamond technology was the solution. The EDT EURODIMA customer Seidl, the local concrete cutting specialist was assigned by the site’s principal.

To avoid encumbrances to the rolling traffic under the bridge, the work was scheduled on weekends only. The Rainerstraße, a heavy traffic city road, was blocked from Saturday 4 a.m. until Monday 5 a.m. The time frame for the concrete cutting works was Sunday 5 a.m. to 3 p.m. During that time, a route diversion was arranged.

An exact planning was critical to carry out the tasks in the ambitious time frame. Seidl’s concept was to do the separating cut with three hydraulic 30 kW wall saws and an electropneumatic wire saw. The cut dimensions were 20 m length and 40 cm depth, and 60 cm depth at the foundations. In the range of the flyover, twelve I-beams (20 cm) and some steel plates (30 cm / 10 cm) had to be cut.

Moreover, two openings with dimensions 1x1x0.8 m had to be cut for bridge underpinning. Here, a steel beam with 0.5 m height had to be cut, as well as a concrete-lined steel construction (0.8 m height, 0.6 m width) that is the bridge underpinning at the pedestrian passageway. Therefore, the big EDT EURODIMA wire saw wb12s was used. The selected diamond wire was the DS40FBLUE, with 40 beads per running meter, 10.5 mm outer diameter and 2 mm active wear layer. The cutting ability of that new diamond wire perfectly met the high expectations.

To finish the wall saw tasks in due time, Seidl consulted the EDT EURODIMA technician and chose to use the diamond saw blades type WS30 with the new, innovative DURAMANT® segments, with width 5.0 mm for ø 600 mm, 4.7 mm for ø 825 mm and 4.4 mm for ø 1200 and 1500 mm saw blades. The well-proven EDT EURODIMA wall saws WM90 with hydraulic unit HA300 in combination with the high-quality DURAMANT® tools accomplished this challenging task reliably as usual

Seidl deployed six concrete cutting experts so that all machines could be operated efficiently. Despite the change from wintertime to summertime, thus that night being “shorter” by one hour, work started early at 5 a.m. and the task was completed at 2.30 p.m. Good coordination was needed to employ all machines in an economical way on the bridge. Regardless of the bad weather, all concrete cutting tasks were accomplished so that the principal showed complete satisfaction.

The stable hydraulic units and wall saws have shown their reliability for a long time. This operation demonstrated the well-experienced concrete cutting professional users of our customer how versatile the new DURAMANT® products are: Not only with high frequency technology and drill units but also with hydraulic systems, they perform strongly.