TULA reaches first milestone

Pleased and happy: the tunnel builders with the two patronesses (left: Imke Gembalies, right: State Minister Dr. Herlind Gundelach) in front of the cutterhead of TULA. The rest of the borer is still located inside the newly completed tunnel section. (Photo: European XFEL GmbH)

After less than two months, the tunnel boring machine TULA broke through the wall of its reception shaft. The first 480 meters of the tunnel system are thus completed. The tunnelling team was greeted in the shaft by the two patronesses.

When the tunnel boring machine TULA (TUnnel for Laser) set out for its “maiden trip” at the beginning of July, it was not at all sure that it would reach its goal on schedule eight weeks later. As it is, the old miners’ proverb “It’s always dark in front of the pick” also applies to tunnel building. How long the machine will actually take depends on the composition of the soil and on the presence of unknown potential obstacles underground. And of course, the skill of the tunnel builders in guiding the colossus through the earth, compensating for a little unevenness or “sensing” possible changes in soil composition in time, is equally important. To do this, they sometimes even have to slip in diving suits into the slurry in front of the machine to check the tools fixed on the cutterhead.

All this apparently worked out perfectly, which also pleased the tunnel patroness, Hamburg’s State Minister for science Dr. Herlind Gundelach. At the bottom of the 20-metre-deep construction pit that will one day house the switchyard building for the tunnel fan of the X-ray laser, she complimented the tunnel builders with the words: “Saint Barbara is well-disposed towards the ’Herlind Tunnel’. TULA has even reached its goal a few days earlier than planned.” With the assistance of the patroness of the tunnel boring machine, Imke Gembalies from the European XFEL GmbH, she distributed a bottle of beer from Hamburg’s brewery Gröninger and a herring bread roll to each of the 30 tunnel builders present and asked them about their experience underground.

During the coming weeks, TULA will be dismantled, the various parts transported back to Schenefeld and then reassembled again for its second assignment direction Osdorfer Born. The building of the 594-metres-long tunnel section will begin in early November. “I wish all the people involved in the project good luck and beg Saint Barbara to go on protecting the tunnel builders from all dangers and keep unexpected negative developments at bay from the project”, State Minister Gundelach said.

Joint news of DESY and European XFEL GmbH