Tunnelling Ends on First La Cabrera Tunnel on Madrid-Valencia High Speed LineA joint venture formed by FCC and Sando completed the first tube of the La Cabrera tunnel, the longest tunnel on the Madrid-Valencia high speed link between the Valencian municipalities of Siete Aguas and Buñol. The breakthrough took place on 25th January at 2:00 p.m. Tunnelling of the first La Cabrera tunnel, 7,156 metres in length, got under way from the Siete Aguas mouth, using conventional methods and drilling and blasting to dig 1,158 metres. Similarly, from the Buñol mouth, crews tunnelled 5,998 metres by means of a Herrenknecht double shield hard rock tunnel boring machine. Visit www.herrenknecht.com While boring through the rock the nearly six kilometres of TBM-driven tunnel, the FCC-Sando JV beat the daily advance record five times, setting a new world record of 83.2 metres excavated and 52 rings of precast reinforced concrete segments installed in a single day, shaping a 8.75 m ID tunnel. Crews beat the record a first time last 27th September, with 65.6 metres excavated in a day. On 1st October, a new record was set (67.2 m), that was beaten on 19th November (72 m) and again six days later (80 m). The last record (83.2 metres) was achieved on 1st December. The average daily production rate was 21 segmental rings, or 33.6 metres per day of finished tunnel. Click here and here.The assembly and setting of the TBM was completed on 18th July, 2007, though it did not begin to churn forward until 31st July. Shifts of 24 workers, working uninterruptedly 24 hours a day, operated the machine continuously. Five months and 25 days after the TBM moved forward into the ground, it is possible to travel all the way through the tunnel from one end to the other. Not only the 11.2 km Siete Aguas-Buñol section includes the La Cabrera tunnel but also two other tunnels, that cross a steep mountainous terrain. The construction of the Siete Aguas tunnel, 424 m in length, is proceeding and its conclusion is expected for mid-2008. The 1,856 m Buñol tunnel is finished since July 2007.The La Cabrera tunnel is the first in the history of the Valencian Community to be built by a double shield TBM. It is a twin bored tunnel excavated in carbonated rocky materials (limestone, dolomites, marly limestone, etc.) Click es/95. Visit www.adif.es and www.fcc.es 08/08.