Case Studies: Current Projects
Custom Single Shield TBM bores Spain's Madrid-Valladolid rail line
- Machine Type: Single Shield TBM
- Diameter: 10 m (32.8 ft)
- Tunnel Type: Rail
- Tunnel Length: 10.5 km (6.5 mi)
- Owner: Administrador de Infraestructuras Ferroviarias (ADIF)
- Contractor: Joint Venture (Constructora Hispanica / Azvi / Brues y Fernandez / Copcisa)
- Location: Asturias, Spain
Project Overview
The Pajares Lot 4 tunnel is part of Spain's AVE high-speed rail link. The entire 49.5 km (30.8 mi) long tunnel will connect Asturias to the Madrid-Valladolid high-speed link. The route is divided into four lots, with two tunnels for traveling both east and west.
Project owner, Administrador de Infraestructuras Ferroviarias (ADIF), awarded the construction contract for Lot 4, a 10.5 km long section of tunnel, to a joint venture of Constructora Hispanica, Azvi, Brues y Fernandez and Copcisa. The joint venture chose a 10 m (32.8 ft) diameter Single Shield TBM to bore the tunnel. The TBM was designed by Robbins and built by Mitsubishi Heavy Industries. The machine was pre-assembled at a shop in Spain and final assembly was completed onsite.
The machine began boring in August 2006 through sandstone, shale, limestone, molasse, and volcanic rocks with Unconfined Compressive Strengths (UCS) of 40 to 90 Mpa (6-13 ksi). Robbins' Single Shield design allows the machine to cope with this fractured and varied rock. The machine can also erect 500 mm (19.7 in) thick pre-cast concrete segments to support the tunnel walls in troublesome geology.
The TBM features 17 inch (432 mm) cutters and is powered by 5,180 kW (6,946 hp) to generate a maximum cutterhead thrust of 16,814 kN (3,780,000 lb). The back-up system for the machine consists of open gantries.
Updates of this project will be posted as boring continues.
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