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| TUNNELLING
High precision tunnel segments STRABAG subsidiary Mobil Baustoffe specializes in the production of on-site concrete for large scale construction projects such as tunnels but also produces high precision prefabricated segments for TBM drives
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ince its founding 1998, the specialist company has supplied concrete and segments to a large number of infrastructure projects and is involved in many projects. One of those projects is the Woodsmith Project – the construction of a 37 kilometres long Mineral Transport System for the world’s largest Polyhalite resource. Rapidly increasing and urbanized world populations require the use of fertiliser for more efficient food production. The mineral Polyhalite provides this by sustainable and low carbon means. From the Woodsmith Mine, the mineral will be extracted via a mine shaft from 1,550 metres below ground and transported on the underground conveyor based Mineral Transport System (MTS) to the Materials Handling Facility in Teesside where it will be granulated. After being processed, the
product will be transported to port via overland conveyor system and the majority will be exported to overseas markets. STRABAG, the parent company, was 2018 awarded with the design and construction of the 37 kilometre long tunnel, including Rail Professional
the MTS. The total contract value amounts to several hundred million Euros with a one hundred per cent share for STRABAG. The scope of work comprises 300 metres of open cut, 100 metres SCL tunnel, 36.1 kilometre segmental lined tunnel boring
machines (TBM) drive, underground caverns, a minerals transport conveyor belt system as well as tunnel utilities include 66 kV mine power and 900mm gauge maintenance railway system. Tunnel boring machines (TBM) are increasingly used in modern tunnel construction. The high level of mechanisation in tunnelling is making tunnel construction safer and more precise. For TBM drives high precision reinforced segments – sometimes with fibres – are needed. This is, where Mobil Baustoffe comes into play of this project, which is located in north-eastern England. Mobil Baustoffe is responsible for the concrete production for the high precision tunnel segments for the TBM driven tunnel. The segments are fabricated on site in a factory specially set up for the project, including the production of steel reinforcement cages and the concrete batched on site. The entire production line up was laid out for an equivalent of 20 metres per day of TBM advance. The anticipated productivity was achieved using local labour, many with no previous segment manufacturing experience after a learning
