References

The Helsinki Rautatientori metro station project improved the station's fire safety and renewed its technical systems.

We made rock openings at the entrances to the underground tunnels for new smoke-tight doors by wedging. We also carried out the bolting and shotcreting required for the new structures and a significant amount of chemical grouting to seal leaks in the old shotcrete structures.

As part of the Västlänken project, we worked together with Bohus Bergsprängning AB to build a specialised tunnel section using the New Austrian Tunneling Method. The clay-filled rock section was treated with a lime-cement mixture and sprayed in advance, which enabled the tunnel to be excavated through the layer of clay-filled rock.

66 spray-concreted arch elements were installed over a distance of approximately 30 m. The tunnel was constructed in six different longitudinal sections in stages. This required the installation of 2500 drill bolts and 3500 m² of grouted shotcrete surface, 300 m of tunnel foundation anchoring and 200 m of drainage pipe installation. Approximately 2000 m3 of mass was removed from the tunnel section.

The project involved constructing a connection tunnel from the new adult psychiatry building of Pirkanmaa Hospital District to the existing service facilities.

Blasting and rock reinforcement work was carried out in compliance with the strict requirements of the hospital environment, which houses numerous vibration-sensitive devices. All blasting operations required coordination with the hospital's central control room and careful consideration of adjacent structures.

The scope of work included 54 meters of tunnel excavation, 250 m³ of shotcreting, approximately 1,300 rock bolts, and 300 meters of grout hole drilling.

As part of the joint HYBRIT project between SSAB, LKAB and Vattenfall, an experimental hydrogen storage facility was built in a rock cavern. The project involved the excavation of a total of approximately 6000 m3ktr of rock, which included a 100 m3 capsule-shaped storage tank about 30 m below ground level. In this case, the Lined Rock Cavern (LCR) structure is used to store the hydrogen, where the rock is coated to seal the reservoir.

As part of the reorganisation of Stockholm Vatten's wastewater treatment activities, a transfer connection will be made via a rock tunnel from the decommissioned Bromma plant to the expanded Sickla plant. We are contracting the E2 tunnel section in the Stockholm city centre area.

The contract includes the excavation, shotcreting and reinforcement of a 2.8 km long waste water tunnel and the excavation of a working tunnel for this work. Work is still ongoing

In the Västlänken project, Trafikverket will build around eight kilometres of new double track for both short and long-distance trains and three new stations in central Gothenburg. Six kilometres of track will be located in a tunnel.

We have subcontracted a one-kilometre section of a twin-track tunnel, a parallel service tunnel and a working tunnel to enable the construction of the tunnel to the NCC-Ways & Freytag consortium. In addition to the excavation of the tunnel, which amounted to some 230 000 m3, we have also carried out the reinforcement, grouting and shotcreting of the excavated section.

Special expertise was required for the excavation of the underpass of the old double-track tunnel known as Gårdatunneln. To support the crossing area, reinforced arches were constructed from HEB blocks using sprayed concrete.

The assignment started with the excavation of a tunnel (730 m) and level and excavation pits (1070 m) with profiles ranging from 17 to 25 m2. In addition, ventilation shafts were excavated by long hole excavation. Tunnel spaces were reinforced with Swellex bolting (8,300), wire bolting (4,300 m) and hanging mesh nets (8,500 m2). Since then, the contract has continued with both rigging work and production drilling, with a gradual increase in production volume.

Since then, the contract has continued with both tunnel development and production drilling, with production volumes gradually increasing.

The Henriksdal wastewater treatment plant renovation project refurbished the plant and increased its capacity.

We built a 400-metre-long working tunnel under the reservoirs to enable efficient demolition work. In the second phase, we carried out the roof raising of the existing waste water basins by excavation and the associated reinforcement works. In the third phase, we reinforced the existing tunnels and basins for the next phases of work.

As part of the Henriksdal wastewater treatment plant renovation project, we excavated a technology tunnel (60 000 m3ktr) and five associated shafts. The wastewater treatment plant was partially in operation throughout the work, which required constant attention to vibration-sensitive process equipment.