Whether machine-assisted driving in tunnel construction or tunnel renovation and expansion, underground tunnelling creates particularly complex challenges for people and machines. The digging of tunnel profiles, the creation of cross passages and caverns as well as the breaking out of material from the ridge and crown area are an elementary part of the work. The loosening of stone, masonry and concrete in very limited spaces is often not so easy to master: Conventional excavators and demolition robots with articulated arms in particular reach their limits when working in the ridge area or profiling caverns due to their design.
TML's tunnelling machines have a significant advantage over conventional excavators in tunnel projects: With the robust telescopic boom, which can be continuously rotated through 360 degrees, attachments such as hydraulic hammers and drum cutters can be used with higher flexibilty and in a time-saving manner. Even difficult-to-reach ridge areas and extreme minimised space conditions are no problem. The unique telescopic kinematics create a working area that reduces the need to move the machine to a minimum, thus not only saving valuable time but also increasing flexibility and working safety. The fully enclosed and shielded boom reliably protects the internal telescopic cylinder and the hydraulic hoses against the ingress of dust and rock.
Work safety is significantly increased by the telescopic boom and the possible radio remote control of the machines. This means that tunnelling work can be carried out with sufficient safety distance from the danger zone. In addition to the robust telescopic boom, a comprehensive LED lighting package and, on the larger models, a FOPS-protected upper cabin are standard features of our tunnelling machines. TML's machines have proven successfully in tunnel construction: In the Swiss Alps, the compact UNIDACHS 220 has been instrumental in expanding the profile of the Maroggia tunnel for the Swiss Federal Railways (SBB). Two UNIDACHS 220 are being used for Grand Paris Express.
A hydraulic hammer weighing approx. 350 kg was used as an attachment.
In metallurgy, the name UNIDACHS has been synonymous with the world's best and safest debricking machines for decades. The technology is also increasingly proving its value in mining and tunnelling.
Marti Tunnelbau AG on behalf of SBB
Maroggia Tunnel on Lake Lugano in Switzerland
The tunnel cross-section had to be extended in a very confined space while train traffic continued. Numerous works for anchoring the crossbeam in the ridge had to be carried out overhead - the use of a conventional articulated arm excavator was impossible.
Two UNIDACHS 220 are being used on Grand Paris Express, one of Europe's largest infrastructure projects for the extension of the Paris Metro: equipped with a milling cutter, hydraulic hammer, a tool for setting steel arches and a tumbling spray nozzle for shotcrete work, the two machines are being used in the profiling of tunnel cross-sections for the construction of Line 15, among other projects.
The new Grand Paris Express metro line will connect the Paris regional line to the Paris metro network. Grand Paris Express is currently the largest infrastructure project in Europe and, with a length of around 200 km, will almost double the existing Paris metro network. Completion is planned for 2030.
Thanks to the unique kinematics of the UNIDACHS 220, we were many times faster than with conventional articulated boom machines. Especially when breaking out the recesses for anchoring the crossbar, our employees were thrilled by the high precision they were able to achieve. And the remote control contributed massively to the high level of work safety.
Martin Frauenlob, Site Manager at Marti