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measures, such as polymeric paste injection and polymeric membranes, proved insufficient, while additional excavation was prohibitively expensive due to the walls being largely complete already. Instead, engineers turned to unorthodox means of channeling the water by installing a first-of-its-kind composite lining. After four years of work, the rate of water infiltration had been reduced by 40 percent. By 2014, the difficulties of constructing the
Pajares Base Tunnel had become thoroughly apparent. Over the course of one decade, the initial plans of the tunnel were altered on 15 occasions. The costs of its construction has overrun substantially, rising to €3 billion against the originally budgeted price of €1.8 billion.
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sealing the tunnel against water infiltration. Furthermore, the geological conditions surrounding the tunnel featured multiple areas of high compressive tectonic stress regimes, such as thrust faults, which necessitated greater levels of support to be installed in the tunnel than had been originally anticipated. Despite this, the boring process was completed eight months ahead of schedule. On 11 July 2009, a ceremony was held to mark the completion of the tunnels.
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deployment of unique engineering solutions, the infiltration issue has proved to be difficult to address, and questions have arisen as to if its electrification is even practical. As a result, the fitting-out of the tunnel has been delayed by several years. Early on, the through route was expected to be open in 2010. Finally, the tunnels were opened to passenger traffic the 30th
November 2023.
106:. It was reportedly regarded as being one of the largest and most challenging civil engineering projects anywhere in Europe at that time. The tunnel would replace a relatively steep and winding conventional route through the mountains that had limited train speeds to a maximum speed of 70 kmph, while the new line was envisioned to facilitate speeds of up to 300 kmph.
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Work commenced on the
Pajares Base Tunnel following its authorisation in 2003. During the construction process, multiple setbacks were incurred on the part of the geological conditions present, particularly the copious ingress of water into the tunnels. Despite multiple years of remedial work and the
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in the vicinity of the bores had been previously identified by surveys undertaken in the 1980s; accordingly, vast quantities of water continuously infiltrated into the bores. It has been alleged by construction workers that management had prioritised maintaining a high rate of progress over properly
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However, despite this milestone being attained, the fitting-out of the tunnel proceeded at a very slow rate due to the water infiltration issue; up to 2,200 liters of water was reportedly entering the tunnel every second, much of it via cracks in its concrete walls. Conventional waterproofing
168:) between July and September 2005 on the León slope and between April and July 2006 on the Asturian slope. The tunnel boring machines extracted 4.3 million m³ from the tunnels. The bulk of the excavation work for the Pajares Base Tunnel was performed by
98:, forming a part of the main line between Madrid - Oviedo main line. The most prominent civil engineering work of this line is the twin-bore Pajares Base Tunnel, which necessitated a length of 24,667 m (80,928 ft) to traverse the
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During 2003, the Public Works
Ministry awarded a €1.8 billion contract for the Pajares Base Tunnel's construction to a consortium involving the majority of Spain’s major civil engineering firms, including
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to supply tunnel safety and security systems for the 12 tunnels of the
Pajares New Line project, including the Pajares Base Tunnel. Despite plans for the tunnel to be electrified by
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throughout its 24,667 m (80,928 ft) length, questions have been raised if electrification is feasible due to the high level of water infiltration present.
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Pablo
Valenzuela, María José Domínguez-Cuesta, Mónica Meléndez-Asensio, Montserrat Jiménez-Sánchez, José Antonio Sáenz de Santa Marí (2015).
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as well. It had been anticipated that the completed tunnel would facilitate a journey time of 2 hours and 12 minutes between
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172:(TBMs). The construction soon encountered substantial amounts of underground water, the presence of relatively porous
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234:"Asturias goes through the time tunnel: great chronicle of the historic day in which the Variant saw the light"
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417:"In-situ stress amplification due to geological factors in tunnels: The case of Pajares tunnels, Spain"
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134:. As originally planned, both bores of the Pajares Base Tunnel would have been furnished only with
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458:"Active sinkholes: A geomorphological impact of the Pajares Tunnels (Cantabrian Range, NW Spain)"
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Its execution began with five TBMs (four for the large tubes and the fifth for the gallery from
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During the early decades of the 21st century, Spain allocated a large proportion of
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arrangement would be installed instead, as it was thought that the presence of
260:"Spanish high-speed line under mountains opens after 20 years of construction"
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50:. The 24,667 m (80,928 ft) length tunnel forms a key portion of the
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347:"Fomento prevé concluir las obras de la variante Pajares a finales de 2020"
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high speed rail network. On 1 March 2002, it was announced that
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299:"€1.2 billion over budget and still no opening date in sight"
333:"Composites perform water rescue in high-speed rail tunnel"
74:-supplied infrastructure funding into the expansion of its
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for the design of a new 50 km high speed railway between
381:"Pajares: A Wet, Warm Tunnel, and other White Elephants"
188:(ADIF) had awarded a €53m contract to a consortium of
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494:: CS1 maint: multiple names: authors list (
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399:"Trend Analysis of Long Tunnels Worldwide"
184:During June 2020, it was announced that
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82:(GIF) had awarded a €5·18m contract to
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415:Hijazo, T. and Vallejo, L.I. (2012).
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591:Buildings and structures in Asturias
315:. railwaygazette.com. 1 March 2002.
404:. Mineta Transportation Institute.
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509:Cuenca, Oliver (20 July 2020).
331:Mason, Karen (7 January 2018).
313:"Pajares base tunnel contract"
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297:Mendez, Rafael (7 May 2014).
606:Railway lines opened in 2023
474:10.1016/j.enggeo.2015.07.007
429:10.1016/j.enggeo.2012.03.007
397:Pyeon, Jae-Ho (March 2016).
198:San José Construction Group
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379:Bent, Mike (Autumn 2014).
353:(in Spanish). 15 June 2017
611:Tunnels completed in 2023
586:Railway tunnels in Spain
214:León-Gijón railway line
16:Railway tunnel in Spain
335:. compositesworld.com.
170:tunnel boring machines
132:Constructora Hispánica
54:line between León and
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596:Transport in Asturias
301:. english.elpais.com.
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562:43.01944°N 5.77528°W
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468:: 158–170.
244:30 November
580:Categories
550:43°01′10″N
270:2023-12-03
220:References
143:dual gauge
88:Geoconsult
553:5°46′31″W
482:0013-7952
161:by 2010.
124:Ferrovial
208:See also
202:25 kV AC
196:and the
120:Dragados
92:La Robla
357:5 March
116:Acciona
102:of the
36:tunnels
33:railway
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264:Trains
190:Alstom
159:Oviedo
155:Madrid
130:, and
402:(PDF)
384:(PDF)
194:Indra
174:karst
166:Buiza
128:Sacyr
84:Ineco
56:Gijón
48:Spain
496:link
478:ISSN
443:link
359:2020
246:2023
157:and
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