Wirth TBM Bores Campanas Tunnel on Canal de NavarraThe Itoiz dam and artificial lake are located in the north of Navarra in northern Spain, 30 km from Pamplona. From this 418 cu hm water reservoir (finished in 2005), a 177 km canal will be built with the purpose of irrigating 57,000 hectares of land in central and south Navarra, an area traditionally suffering from water shortage. A further benefit is the coverage of the potable water requirements of Pamplona and its environs. In addition, a hydroelectric plant is planned that will generate 53 MWh of power. The Campanas tunnel has to be built to cross mountainous landscape and connect the artificial lake with Pamplona. With the new tunnel, the canal will cross underneath highway AP-15, road N-121 and the Pamplona-Castejon line.Tunnelling of the Campanas tunnel, on section 4 of the Navarre canal, began on 7th August, 2005 following the official launch on 26th July of a new Wirth telescopic double shield TBM TB 619 E/TS. The price of the shield machine is EUR7.64 million. Section 4 has an overall length of 9,033 metres, of which 4,300 m of tunnel (the 4,021 m Campanas tunnel built by TBM and the 280 m Ucar-Olcoz tunnel). To meet a tight delivery schedule, the shield was transported to the site by Wirth without being disassembled. A compact transport device was designed to transport the shield and the back-up system, which reduced drastically the setting-up phase.The diameter of the cutterhead is 6,190 mm (lined diameter of 5.4 m). The cutting head is equipped with 40 disk cutters, 39 of 17" (six at the centre, 30 on the face and three gauge cutters), which will cut the rock leaving tracks spaced every 18 cm and a 17" twin disk cutter, which is hydraulically driven. The weight of the TBM is 480 tons (750 tons with the back-up) and the length of the shield is 12 m (130 m with the back-up). The installed total power is 2.400 kVA. The installed total power of the main drive of the cutterhead is 6 x 286 kW. The nominal thrust and maximum thrust are 25,000 and 34,500 kN respectively. The nominal torque is 4,000/2,000 kNm at 3.9/7.8 rpm.The tunnel will be lined with straight segmental rings comprising of six precast concrete segments and a curved invert segment, 1.4 m long and 250 mm thick. CBE made the moulds and Sorigue produces the segments. Visit www.cbe-tunnels.comThe geology is Pamplona marls (35-40 Mpa), with some Perdon conglomerate layers (limetone cores in matrix), with resistance of 120 Mpa. Mucking-out with Schoma loco and Muehlhauser wagons. Visit www.schoema-locos.de and www.tunnelling-equipment.comThe build and support method for the Ucar-Olcoz tunnel is still in discussion, but it is most probable that this tunnel will be excavated with a roadheader (in top heading and bench sequence) from one side. Tunnelling is to commence in the winter of 2005/06. The tunnel is located between the Tirapu and Campanas tunnels.The builders are Sacyr, Copisa and Arian Construccion. Their contract also includes sections 5 and 18. Section 5 includes the 1.2 km Tirapu tunnel and the 480 m Anorbe-Bekaira tunnel, at the end of the section. The Tirapu tunnel is being excavated by a Voest-Alpine AM 50 roadheader in top heading and bench sequence from the two sides. To date, 50 metres of top heading has been driven from the north. Excavation began in April 2005, after one month working on the preparation of the portal. Forepoling of the tunnel roof with tube umbrellas is under way from the south, drilling 65 cm holes and installing each metre TH steel arches supplied by Tedesa and other supports. A GHH 11.2 dump truck is used to haul the spoil. Geology is dark red marly clays with interbedded brown sandstone featuring fractures filled with gypsum. Visit www.vab.sandvik.com, www.ghh-fahrzeuge.de and www2.gdfsa.comThe Anorbe tunnel will be driven from one side by a Caterpillar excavator equipped with a hydraulic hammer and from the opposite side by the drill and blast method in full section, using a Tamrock jumbo. The steel tube umbrellas have been completed and tunnelling is starting. Skips for the mucking-out. Geology is clay with dispersed whitish/ochre sandstone channels. Visit www.cat.com and www.tamrock.sandvik.comThe support of the Tirapu tunnel consists of resin bolts in certain zones, fibre-reinforced shotcrete (35 kg/cu m) -also in the Anorbe tunnel- and final lining with sulphate resistant concrete.The Campanas tunnel, along with sections 5 and 18, is expected to be completed in February 2007. The three sections represent a total length of 17 km. Click es/72. Visit www.riegosdenavarra.com, www.gruposyv.com and www.copisa.com 36/05.