Multifunctional Machine for Tunnel Redevelopment
Works in Confined Spaces

For the redevelopment of the Maroggia Tunnel in Switzerland, the Multiripper 220 multifunctional machine fitted with a hydraulic hammer ensured that the amount of time needed to remove the existing masonry and produce recesses in the roof was reduced to a fraction of what is usually required. The machine’s 360° rotating boom particularly facilitated work overhead. Thanks to the compact form of construction, it was possible to keep train services running in the tunnel on one track while work forged ahead.

GTA had been searching for a carrier unit to accommodate various attachments for a long time. It had to be sufficiently compact to remove material under constricted conditions when redeveloping tunnels. The machines available on the market were only suitable to a certain extent for working overhead in particular. As a result, GTA got in touch with TML Technik, for their telescopic boom of the Unidachs 220 ripper, which TML originally devised for the metallurgical industry, can rotate by 360°. The machine, which GTA supplies under the name Multiripper 220, is suitable in mining and tunnelling, among other things for producing cross-passages, profiling tunnel cross-sections, scaling with a hydraulic hammer or a cutter as well as clearing, using different types of shovels. Furthermore, it can accommodate shotcrete nozzles as well as drill booms and tools for placing arches and anchors. The operator is able to work at a safe distance thanks to the remote-control system.

Maroggia Tunnel Redevelopment

The redevelopment of the Maroggia Tunnel on the Lake of Lugano provided an excellent opportunity to try out the capabilities of the MultiRipper. The SBB had decided to enlarge the tunnel cross-section within the scope of the Four-Metre Corridor Basle–Chiasso/Ranzo” project.

During the project, the old masonry had to be removed and recesses created in the roof to install a crossbeam there. As a result, a great deal of work had to be tackled overhead, for which purpose articulated excavators are only suited to a certain extent. Some 200 trains travelling at roughly 80 km/h used the neighbouring track every day as work forged ahead. In this case too, the telescopic boom turned out to be the perfect choice since thanks to its design, no parts ever protruded into the other track’s clearance profile.

The Marti Company, the general contractor for the project, recognised the potential of the MultiRipper 220’s telescopic boom capable of rotating 360° and leased the machine for the duration of the construction period. For working in the tunnel, the machine was fitted with a hydraulic hammer weighing some 350 kg and set up on a platform carriage. In this way, the construction train could be driven out of the tunnel whenever space was needed to place concrete.

In spite of its compact size, the machine with its boom was able to reach the complete cross-section without having to be relocated, accomplishing the work in the roof with high precision. As a result, Marti decided to purchase the
MultiRipper 220 after construction had been completed so that it could be deployed for other projects.

x

Related articles:

Construction Equipment

Multifunctional Machine for redeveloping Tunnels given constricted Space

GTA had been searching for a carrier unit to accommodate various attachments for a long time. It had to be sufficiently compact to remove material under constricted conditions when redeveloping...

more
Issue 03/2013 Securing the Roadway

Securing the Roadway after Blasting with the Paus Scaler 853 S8

1. Barring down and Scaling – important for Securing the Excavation Scaling or barring down the roof and ribs underground largely serves to secure the excavation following blasting and for...

more
Issue 06/2014 Short Tail Excavators

With Hammer and Chisel: Excavators at the Albabstieg

The required precut in the terrain as well as the working and storage areas for the Albabstieg Tunnel has long been completed. The first 300 m of the 5.9 km long section, over which the trains between...

more
Issue 04/2012

Report on Redeveloping Railway Tunnels

1 Background and Aims of the Working Group The Working Group on “Tunnel Redevelopment” was prompted by the findings obtained from carrying out the first 2 projects concerned with enlarging the...

more
Issue 03/2009 Construction Equipment

New Boom for compact Radius Excavator 328D LCR

A tunnel excavator must take advantage of constricted space and in the process usually fulfil rigorous work for a good 24??h without a break. Generally this machine is subjected to particular strain,...

more