Ineco has participated in an assisted driving test with 5G technology in the Cereixal tunnel on the A-6 in Lugo. The demonstration, which took place in May, is part of the 5G Galicia Pilot project promoted by the Ministry of Economic Affairs and Digital Transformation, which also involves Telefónica, Nokia, Stellantis, CTAG and SICE.

During the test, the vehicle received information from the ‘smart’ tunnel, which had been equipped with 5G sensors that transmit data and images in real time: accident warnings, congestion, slow traffic, weather conditions outside, etc. Ineco developed the system that integrates and presents the information to the driver.

The arrival of high-speed rail in this region in northwestern Spain had its first historical milestone at the end of 2011, with the entry into operation of the 150-kilometre stretch between Ourense, Santiago and A Coruña. After the service commissioning of the line between Olmedo and Zamora in 2015, all that remained to complete the connection between Galicia and the centre of the Iberian Peninsula was the construction of three sections totalling approximately 230 kilometres: Zamora-Pedralba de la Pradería, Pedralba de la Pradería-Taboadela and Taboadela-Ourense.

The difficult route between Pedralba and Ourense

Built for the most part on two separate tracks, the 101-kilometre section between Pedralba and Ourense crosses the different mountain ranges that form the Central Ourensan Massif, a route that the AVE will be able to cover thanks to the construction of 32 viaducts and 31 tunnels, many of them bi-tube, or with one tube for each track. More than 60% of the route was either underground or over viaducts and required special works: in total, the section has almost 11 kilometres of viaducts, the longest of which is the Requejo viaduct (1.72 km), and 126 kilometres of tunnel (62.45 km on the right-hand track plus 55.87 km on the left-hand track and 7.84 km of double track), the longest being the O Corno tunnel (8.6 km).

MADRID-GALICIA HIGH-SPEED LINE. The Madrid-Galicia HSL is co-financed by the European Regional Development Fund (ERDF), ERDF/Cohesion Fund 2007-2013 and Spanish Multiregional OP 2014-2020.

The works that are covered in this report belong to this complex route between Pedralba and Ourense, which Adif Alta Velocidad constructed to provide the highest levels of railway technology, with standard-gauge double track (1,435 mm) throughout the route, and designed for speed limits of up to 350 km/h, with 2×25 kV 50 Hz alternating-current electrification, ERTMS Level 2 and Asfa traffic control systems, and a GSM-R mobile communications system.

Five of the most notable works

THIS SECTION FEATURES A NUMBER OF INFRASTRUCTURES THAT STAND OUT FOR THEIR COMPLEXITY, EITHER IN TERMS OF THE CONSTRUCTION METHODS USED, THEIR DIMENSIONS OR THEIR ENVIRONMENTAL CHARACTERISTICS.

1. The jacked caissons of the Requejo tunnel

Two caissons 80 and 100 metres long jacked under the conventional railway tracks complete the Requejo tunnels.

In the foreground, shoring of the track. Behind, crossways, one of the two caissons already executed. In the background, the opening of the Requejo tunnel.

Several kilometres from Pedralba, the AVE works are progressing through the mountains of the Sanabria region with several notable actions, including the construction of the caissons jacked into the Requejo tunnel, structures built in situ at the western opening of the Galicia side and jacked under the railway tracks, allowing Adif to maintain rail service on the Zamora-A Coruña national gauge line, which intersects with the new high-speed line at this point.

This intersection of the high-speed line with the conventional track was resolved by constructing two reinforced concrete caissons measuring 8.5 metres high and 8.5 metres wide on the inside, with lengths of 79.5 metres for the caisson for the right-hand track and 100.5 metres for the caisson on the left.

In their final position, the caissons form the cut and cover exits of the Requejo tunnels. The execution procedure included the shoring of the conventional track and the construction of engineering structures on a sliding platform close to their final location prior to subsequent relocation by means of a hydraulic jacking across the track to their final positions.

The shoring consisted of a metal structure that allowed the caisson to be moved without affecting the track, ensuring its stability. Due to the shoring work, trains had to run at a speed limit of 30 km/h during the works, as opposed to the normal speed of the route in this area of over 100 km/h. The speed restriction was necessary as a safety measure because the level and alignment of the track in this situation can generate movements that are not compatible with higher speeds. Given the jacking lengths, the caissons were divided longitudinally into two sections that were jacked successively, each with a corresponding battery of 15 hydraulic cylinders with a force of 300 tons per cylinder. At the same time that the successive 50- centimetre thrusts were carried out, the earth was removed by mechanical means, ensuring that the stability of the tracks was not compromised, until the structures reached their final positions.

2. The Padornelo tunnels

A high-speed tunnel built just 20 metres from the longest tunnel on the entire Spanish conventional line.

Ineco provided construction management for Adif Alta Velocidad on this 6,406-metre tunnel with a 52-square metre clear cross-section, which runs parallel to the tunnel of the Zamora-A Coruña national gauge line, and is located between the municipalities of Requejo and Lubián (Zamora), below the Padornelo mountain pass.

The Padornelo tunnel is part of the Padornelo-Lubián section, and consists of the supporting layer of the single UIC-gauge track on the right, measuring 7.6 kilometres long. The left-hand high-speed track will be executed at a later stage as part of a new project that will adapt the old 5.97-kilometre Padornelo tunnel on the Zamora-A Coruña line for mixed traffic on the left-hand high-speed track and freight on the conventional line.

Construction was carried out with conventional excavation, applying supports consisting of shotcrete, bolts and trusses. Excavation was carried out by blasting the areas with the hardest terrain and using mechanical means (backhoes, hydraulic demolition hammers, etc.) in the softer ground and terrain with lower geotechnical quality.

Execution was determined by the proximity of the tunnel on the Zamora-A Coruña conventional line. During the works, trains continued to run, so certain protocols were established to monitor for deformations in both tunnels, and reinforcements consisting of mesh and shotcrete were necessary in some sections of the old tunnel. 15 connection galleries were also built between the tunnels and an evacuation platform along the existing tunnel, to create the evacuation route necessary for the commissioning of the high-speed line. To carry out these works, the entire track was renovated with UIC 60 E1 rail, PR-01 concrete sleepers and type 1 ballast.

The works were accompanied by a series of specific environmental and landscape integration actions due to the proximity of two protected areas or sites of community importance (SCI):  the banks of the Tera and Tuela rivers and their tributaries. In this regard, different measures were agreed with the regional authorities to prevent the impact on the protected flora and fauna. One example was the treatment of water coming from the tunnel, which was subjected to different processes before being discharged into the waterway, in order to ensure that its physical and chemical parameters complied with legislation. In addition, from the beginning of the works, the waters of the rivers belonging to the aforementioned SCIs had their physical and chemical characteristics monitored and a follow-up assessment was carried on the area’s populations of Pyrenean desman (Galemys pyrenaicus), brown trout (Salmo trutta), freshwater pearl mussel (Margaritifera margaritifera) and aquatic macroinvertebrates.

3. The Espiño tunnels

Two large high-speed tunnels constructed using eight simultaneous excavation fronts.

View of the western tunnel opening. The tunnels were designed to integrate with the hillside as much as possible.

The Espiño tunnels are unique in that they were excavated simultaneously from four fronts: in addition to the two end fronts, there were also two intermediate excavation fronts. To do this, an intermediate gallery was built that ended in a large cavern, from which four additional fronts could be started for excavation in the direction of Madrid and Ourense. The large number of fronts reduced the excavation times for the tunnel.

The bi-tube tunnel runs through the municipalities of A Gudiña and Vilariño de Conso in the province of Ourense. With approximately 8 kilometres on each track and connections between tunnels every 400 metres (20 emergency galleries), it is one of the largest tunnels in the section.

Both tunnels were excavated using the New Austrian tunnelling method, with top-heading and bench, from the eastern tunnel opening, from the western tunnel opening and from the intermediate galleries of attack towards both tunnel openings. The right-hand track has an exact length of 7,924 metres including 30 and 40-metre artificial tunnels in each of the openings for improved visual integration into the hillsides. The remainder (7,854 m) was mine excavated, that is, under natural terrain. The left-hand track has an excavated length of 7,838 m underground, to which 30 and 36 metres respectively were added to each of the openings as artificial or cut-and-cover tunnels, giving the left-hand Espiño tunnel a total length of 7,904 m. Cut-and-cover tunnel structures were also included for improved visual integration into the hillsides.

The presence of metal sulphides and carbonaceous matter in some slatey rock required the use of technosols to treat some of the excavated material in the waste sites. This technique made it possible to control the oxidation of these sulphides, which are capable of generating acidic water, thus creating a reducing environment and also decreasing oxidation kinetics. Technosols also act as a buffer, adsorbing any heavy metals that may be present in the runoff water in the form of leachate, and are eutrophising, which promotes eventual environmental integration.

4. The Bolaños tunnels

The only two tunnels on the Madrid-Galicia line executed BY TBM.

Assembly of the 230-metre-long, 2,900-ton TBM in May 2015.

The Bolaños tunnels are the only ones on the entire line executed by a TBM. Bi-tube by design, they form part of the Vilariño-Campobecerros section, and consist of a 6.96-kilometre right-hand track and 7.91-kilometre left-hand track. The route runs through the municipalities of Vilariño de Conso, A Gudiña and Castrelo do Val, in the province of Ourense.

Both were executed using a TBM with the exception of the first 55.91 metres of the western opening and the first 15 metres of the eastern opening on the right-hand track and the first 76.13 metres of the western opening on the left-hand track, which were executed by conventional methods to move beyond a fault.

The dimensioning of the tunnel cross-section was limited by compliance with the UIC’s health and comfort criteria to ensure high-quality high-speed passenger transport. Following these criteria, the final open cross-section of the tunnels was 52 square metres. The excavation cross-section of the TBM was 9.80 metres in diameter, with 37-centimetre-thick segments of precast reinforced concrete lining with an internal diameter of 8.76 m. The concrete in the segments contains polypropylene fibres as a fire protection measure. The gap between the TBM excavation and segment lining was filled with two-component mortar, a mixture of conventional mortar with hydrated bentonite and silicate.

The waterproofing of the precast lining was achieved by fabricating the segments with a low-permeability concrete; installing a double waterproofing seal at the segment joints; and injecting the two-component mortar into the space that remained between the excavated surface and the ring of segments. The injected voussoir is the primary waterproofing, since, in practice, it is the first barrier encountered by groundwater on its way towards the interior of the tunnel, with secondary waterproofing being that provided by the seals.

The two tubes are connected by 18 galleries, one of which is used specifically for installations. The cross-section of the galleries has an open width of 4.70 m and a lining of 25 cm of plain concrete, with the addition of polypropylene fibres as a fire protection measure.

During the tunnel excavation, a large amount of water was generated by the construction processes, and it was necessary to treat it in a large treatment plant in order to comply with the parameters required by the competent bodies. The suspended solids present in the water were removed using a separation process, with the help of coagulants and flocculants. The pH was adjusted through the use of CO₂ (for basic process water) or caustic soda (for acidic process water).

5. The Teixeiras viaduct

A 100-metre-high central arch over the Arroyo Teixeiras.

The central piers are over 90 metres high, with two half-arches that provide a separation of 132 metres between them.

The Teixeiras viaduct, for which Ineco was in charge of works and environmental management, is without a doubt the most spectacular structure on the entire Madrid-Galicia HSL.

The deck of the Teixeiras viaduct was executed using self-launching formwork, and has a length of 508 metres distributed in eight spans (56 m + 4×66 m+56 m). Its uniqueness lies in the construction procedure chosen to negotiate the Arroyo Teixeiras with maximum respect for the environment. The foundations of the central piers (which are more than 90 metres high) are shared by two half arches, which were erected and angled inward to meet at a fixed point under the deck, providing a separation between piers of 132 metres, equivalent to two spans, which, in addition to minimising the impact on the environment, gives the structure greater transparency and beauty. The Arroyo Teixeiras, a tributary of the Támega River, has protected riverbank vegetation and, on the surrounding slopes, a forest consisting of native species with large chestnut and oak trees.

The construction of a large structure like the Teixeiras viaduct requires large auxiliary areas to house the facilities that support the construction: from large cranes to site huts; from storage yards to vehicle car parks. For this site, ways of minimising the impact of this area were studied thoroughly. Detailed analysis was carried out on the opening of roads with steep slopes to reduce their grade, areas of auxiliary facilities on bends or between foundations, work platforms adjacent to jobs with strict occupation limits, etc. All of these installations were located on both hillsides that, in addition to being very steep, had soils made up of highly fragmented materials with high potential for displacement of soil that would reach the waterway below in the case of rain.

In order to prevent or mitigate the effects that this soil displacement could have on the water quality of the Arroyo Teixeiras, an ingenious anti-displacement system was implemented, basically consisting of a network of pipes (concrete ditches, pipes, sandpits, settling pools, intermediate reservoirs, etc.) deployed along the access roads to the foundations, which converge at pumping reservoirs located very close to the waterway. To reduce earthwork and facilitate subsequent integration, metal containers were used as pumping reservoirs so that they could be easily removed after the completion of the works.

In the event of heavy rain, sediment-laden runoff was redirected –by means of powerful pumps– to a treatment system located at the height of abutment 2 of the structure, expanding the response capacity in the case of a heavy rains. In this treatment system, coagulants and flocculants were also be used to accelerate separation if necessary.

By the Ineco construction managers Arturo Pastor, Iago Rodríguez-Lorasque and Noelia Cobo, technical engineer Jesús Pena, and environmental worksite managers Iñaki G. Seoane, Enrique M. Agüera and Luis Álvarez-Pardiñas with the collaboration of Raúl Correas, deputy director of Construction V at Adif Alta Velocidad.

Load tests: ready for action

Prior being put into operation, Ineco carried out the load testing of 25 structures and inspection of 70 bridges for Adif on the Olmedo-Pedralba section of the Madrid-Galicia high-speed line.

By Pablo Sánchez Gareta, civil engineer

The Ineco team, from left to right: Jorge Benito, Amadeo Cano, Pablo Martín-Romo, Javier Ortiz, Pablo S. Gareta and Carlos Sánchez.

During the months of March and April 2019, a team of seven specialists from Ineco carried out an important task for Adif Alta Velocidad prior to the commissioning of the new Olmedo-Pedralba de la Pradería section: load testing and inspection of the bridges and viaducts over which the complex route of the Madrid-Galicia HSL runs, all with satisfactory results.

Load tests were carried out on a total of 25 structures, in addition to the main inspections of 70 bridges (14 viaducts, 2 pergolas and 54 underpasses). In the case of the bridges, and since they were newly constructed, the data collected during the inspections provides a baseline situation (zero state) for subsequent analysis and monitoring of the evolution of the structure.

During the tests, which are compulsory for all new bridges with spans 10 metres or longer, actions of actual use of the works are reproduced under controlled conditions.

In other words, checks are carried out to ensure that the bridge is safe, well built and able to withstand the loads of the trains that will travel over it over time. For these verifications, static and dynamic tests are carried out with loaded trains running at different speeds. Data collected by sensors installed on the structure is analysed and the actual and expected responses are compared. The results are sent to the Railway Safety Agency, which is responsible for authorising the entry into operation of the section.

One of the most representative structures that was tested was the Ricobayo viaduct over the reservoir of the same name, measuring 368 metres long and consisting of four spans of between 50 and 155 metres long. For the test, 2 locomotives and 20 hopper wagons loaded with ballast weighing a total of 1,863 tons were used. On the spectacular viaduct over the Tera River, measuring 645 metres long and consisting of nine spans of between 60 and 75 metres, two trains with eight hopper wagons each, weighing a total of 1,536 tons, travelled at speeds of between 10 and 80 km/h.

Gauge matters

While the Zamora-Ourense high-speed section was being completed, a gauge changer was built in Pedralba de la Pradería to enable trains to travel on tracks with two different gauges without stopping. Ineco managed the works, as it is doing in the Taboadela changer at the other end of the section.

By Marta González, and Noelia Sánchez, civil engineers

Ineco is managing works for Adif Alta Velocidad on the Pedralba de la Pradería gauge changer in Zamora, a railway facility that allow uninterrupted travel by trains between Madrid and Galicia, automatically switching from high-speed track in standard gauge (1,435 mm) to conventional track in Iberian gauge (1,668 mm). In addition, at the opposite end of the section, works have also begun on another changer in Taboadela, Ourense, also managed by Ineco.

A gauge changer is a railway facility that allows trains equipped with variable-gauge axles or semi-axles to automatically change their gauge while travelling at a constant speed (approximately 15 km/h) and without the need for human intervention. In Spain, where the high-speed network in standard gauge coexists with the conventional Iberian gauge (IT57), these systems are essential to enable trains to switch from one to another at points where both exist. This is the case of the Pedralba-Taboadela-Ourense section.

From left to right, engineers Noelia Sánchez, head of the ACO unit, and Marta González, manager of the gauge-changer works in Pedralba, Zamora.

The Pedralba gauge changer is a TCRS3 dual gauge changer, that is to say, suitable for both CAF and Talgo technology. Works included the installation of points that connect the Zamora-A Coruña conventional line to the changer at kilometre 112/405. The installations consist of a metal structure with a main trench where the gauge-change platform is located, equipped with a video recording system. On both sides, there are two observation trenches that allow inspection of the rolling system, which also has an automatic de-icing system for Talgo train wheels. This is a temporary solution until the next high-speed section is put into service, at which point the platform and equipment will be dismantled and moved to another changer.

BRIEF HISTORY OF A GROUND-BREAKING TECHNOLOGY

• The first gauge changers were installed in Spain in 1968 in Irún and Portbou to allow Talgo trains to travel to Paris and Zurich.
• Gauge changers spread at the same time as the high speed network; the first generation included different types for each of the two variable rail technologies in Spain (RD by Talgo and Brava by CAF). The dual system, which was suitable for both, was developed later. Adif installed the first third-generation system (TCRS3) in 2009.
• For more than twenty years, Ineco has participated in the design of most of the different generations of gauge changers. Currently, it is also responsible for the maintenance and operation of more than twenty automatic gauge changers throughout Spain.

Vigo-Peinador airport has undergone a number of works in recent years, for example the construction of a new public car park with over 2,500 spaces and the enlargement of the southern terminal building. The Instituto Feiral de Vigo (IFEVI), which is very near to the airport, hosts more than half the international events held in Galicia. A large proportion of attendees arrive by air. The large capacity of the new terminal car park also makes it possible to expand the parking offered by the exhibition centre itself. Given the short distance separating the airport and the exhibition centre, visitors used to travel between the two across the roundabout by which both places are accessed by road. The considerable traffic, the dimensions of the roundabout and the high number of roads connected to it made the walk a long, tortuous journey, where road crossings were challenging and pedestrians were not protected from poor weather conditions.

The pedestrian walkway connecting Vigo-Peinador airport with the Instituto Feiral de Vigo has two purposes. Firstly, there is the intention of exploiting the airport terminal car park to serve the exhibition centre. Secondly, the walkway facilitates the connection between the terminal and the exhibition centre for visitors arriving by air. It establishes a path that connects both places, and on another level avoids the different roads between the terminal car park and the IFEVI centre.

The walkway begins at car park P-1 and ends beside the heavy vehicle parking basins at the exhibition centre. The walkway has a total length of 281 m, with 10 spans of a maximum length of 40 m.

The walkway’s roof is designed with geometrical surfaces whose orientation follows a logical sequence spanning the length of the walkway. The play between different dimensions, densities and angles of the different segments brings the ensemble a dynamic, three-dimensional character.

With more than three million travellers in 2015, according to data from the Ministry of Public Works, passengers have given the ‘thumbs up’ to the Atlantic Axis, a railway infrastructure designed for speeds of up to 250 km/h. The renovation, electrification and duplication of existing routes in addition to the construction of new bypasses and several viaducts, bridges and tunnels have made it possible to transition from the old, non-electrified single tracks to high-performance rail infrastructure: greater speeds, capacity, safety, frequency and comfort for passengers who save up to 58% in travel time. In addition to making renovations to the rolling stock, Renfe has also maintained fares and reorganised rail services which are now divided into “express” and “local” services to cover direct routes between large cities as well as between the urban centres near these cities.

Ineco collaborated in the execution of these projects which have revitalised railway transport in Galicia. According to data from the Railway Observatory of the Ministry of Public Works, the A Coruña-Santiago route is one of the top five regional rail lines for traffic in all of Spain. The Businessmen’s Association of Galicia (Círculo de Empresarios de Galicia) considers that the growth in traffic along this route –a growth of more than 90% between 2008 and 2013– is “a fact that must be directly attributed to the improvement in infrastructure and the implementation of a high-performance rail line on this route of the Atlantic Axis”.

Ineco has worked in construction & environmental management & monitoring, project drafting, inspections & structural testing

In April 2015 the Santiago de Compostela-Vigo section was inaugurated –the third of the three sections that make up the majority of this route which represents a milestone in the modernisation of the Galician railway. The territory of this region is characterised by a great dispersion of populated areas: few big cities –concentrated in costal areas–, many small, isolated areas –especially inland– and very rugged terrain. In addition to these characteristics we can also mention the natural geographical barriers that separate Galicia from the Meseta –barriers that have historically stood in the way of constructing land transport infrastructures, both road and rail.

A far-reaching project

The Axis, spanning 155 kilometres, runs along Galicia’s Atlantic Coast and connects the main areas of industrial and economic activity as well as universities, areas which fuel the demand for transport. The pre-study phase is already underway for the connections A Coruña-Ferrol (63.2 km) to the north of the Axis, in addition to Vigo-Border of Portugal (22.1 km) in the far south of Galicia. The route also connects Santiago with Ourense in the east where this section links up with the high-speed access route to Madrid which is currently under construction.

Initial work on the transformation of existing infrastructure into a modern, high-performance, rapid railway corridor began in 2002. Work was carried out in phases and consisted in installing, along the entire route, a double track with multi-purpose sleepers that will later allow for the change from the Iberian gauge to the standard gauge. The line has also been electrified to 25 kV at 50 Hz, and bypasses have been constructed which have shortened the route by almost 22 kilometres. New sections of the line, owing to the land’s rugged terrain, required several structures: 37 tunnels –totalling a distance of more than 60 kilometres– and 32 viaducts that span a total of 14.9 kilometres. The majority of these structures are located along the section between Santiago and Vigo. This was the most complex part of the route to construct and was the last to begin operating, following both A Coruña-Santiago in 2009 and the Santiago-Ourense connection in December 2011.

In addition to the work concerning electrification, platforms and route corrections (bypasses), adapting the line to new, high speeds also required the remodelling of stations at A Coruña, Santiago de Compostela, Pontevedra, Uxes, Villagarcía de Arousa and Arcade-Apeadero, as well as the construction of new stations: Cerceda-Meirama, Ordes, Padrón-Barbanza, Redondela High Speed and Vigo-Urzáiz, as well as the “temporary” Vigo-Guixar station.

Ineco on the Atlantic Axis

Throughout these years, Ineco has offered their services to the Ministry of Public Works, Renfe and Adif in these highly technical and complex activities, just as they did for the rest of the rail network. Ineco was thus responsible for carrying out tasks regarding the management, coordination and surveillance of construction work, the environmental management of different sections along the whole of the Axis, and the drafting of architectural plans (stations) and railway installations (signalling, safety, telecommunications, etc.).The company also conducted a number of studies in addition to inspections and structural load tests, some as exceptional as that of the Ulla viaduct (see IT54)

Ineco furthermore provided assistance in the management and coordination of tunnel construction work, such as the Vigo access tunnel measuring 8,266 metres long which was carried out using tunnelling machinery, and in the installation of safety systems: electrical installations, ventilation, fire protection systems, etc..

Also worth mentioning in relation to architectural work is the drafting of the construction project for the Vigo-Guixar station which, starting in 2011, has operated as the sole station following demolition of the old building while the new terminal was constructed (in the same location). The Guixar station is a two-storey passenger building boasting 1,000 square metres of space, three platforms measuring 285, 165 and 100 metres long for long-distance and regional rail trains, parking, and bus and taxi stops. When the new Vigo-Urzáiz station began operating in 2015, the Ministry of Public Works decided to keep the Guixar station open to freight transport as well as to local trains.

Ineco also carried out a project, completed in 2010, to standardise architectural elements such as marquees, enclosure gates, decorative elements and locks at nine stations: Redondela, Pontevedra, Padrón, Ordes, Cerceda, Uxes, Pontevedra-Universidad, Arcade and Vilagarcía de Arousa. New passenger buildings were also designed for the latter two stations.

The 155-km line has reduced the average travel time between A Coruña and Vigo by 58% and is one of the most widely travelled routes Spain

With regard to new sections of the line, Ineco coordinated the construction of the Ordes bypass in the province of A Coruña, a section that, over a span of just 7.2 kilometres, required two tunnels and a handful of viaducts. The Vilagarcía-Padrón bypass located between Santiago and Vigo stands out for its complexity, reaching a length of 26.1 kilometres. The company provided technical assistance throughout the management of construction work as well as during the environmental management, control and surveillance of several subsections. The bypass was one of the corridor’s most complex sections with seven tunnels and a dozen viaducts, including one which crosses the Ulla river (spanning a distance of 16 kilometres) and another that crosses over the Sar river –the longest on the Axis- measuring 2.4 kilometres.

Ineco also played a role during each of the phases of development of another high-performance railway connection: the line which links the Atlantic Axis to Ourense from Santiago (see IT18 and 44). The company was highly involved in all of the stages of development of this 150-kilometre section of the line, from project drafting to drawing up operations and maintenance plans, as well as during the construction phases including construction and environmental management services, technical assistance, surveillance and coordination services, etc. Since it entered into service in December 2011, the Santiago-Ourense corridor has also contributed to improving railway connections with the Meseta by reducing existing conventional service travel time by 50 minutes.

Since last August, more than 20,000 residents of this new construction zone have been able to reach the centre of Madrid in 25 minutes thanks to the new halt, without having to go to the centre of Torrejón de Ardoz. Located in this Madrid municipality of 127,000 inhabitants in the north-east of Madrid, the new station belongs to the C7 commuter line and serves the districts of Soto del Henares, Mancha Amarilla and Zarzuela, a zone near the Hospital of Torrejón and the new Casablanca industrial estate. Ineco has carried out the architectural, structural and installation design, as well as construction management for Adif. It is a modular structure of porticos that eliminates the need for interior pillars (open plan) and can be easily adapted to any type of station. The main building, direction Alcalá de Henares, has a rectangular floor, a foyer with waiting areas, automatic ticket vending machines and six faregates, with the possibility of increasing this number to nine. It also has a space for offices, toilets and utility rooms.

Ineco has carried out the architectural, structural and installation design, as well as construction management for Adif

A modular and extendible design

The halt has two buildings, one for each direction. In the interior, all uses are distributed by independent building volumes (‘building within a building’). The station was designed with a capacity to receive 6,000 passengers a day, although the modular structure facilitates its future expansion.

Golden ratio

The geometry of the buildings is based on the golden ratio of a two-metre square, which forms rectangles of 2.8282 x 2m. When doubled they create a module of 5.6564 x 2m, and from the division of this module come all of the internal distances between porticos and different spaces are created.

A light box

The main building is laid out as a rectangular prism with two façades, which provides a maintenance area between them. While the “skin” tinges the interior-exterior light (‘light box’ effect), the outer layer generates permeability and allows the design to be changed.

Platforms

The platform edges are 1.75 metres from the track centres, with a width of 5 metres and a length of 210 metres, with 6 metre slopes at each end. Thanks to the 80 metres of canopy extending from the buildings, passengers are always sheltered when they access the platforms.

Other stations designed by Ineco

Ineco has extensive experience in drawing up architectural designs, as well as in construction management and technical assistance and the preparation of feasibility studies in different types of stations, both overground and underground.

• In Cercanías (commuter rail) we should highlight, amongst others, projects such as the Miribilla station in Bilbao, built at a depth of 50 metres; the two in the Málaga airport access and a few others in the Valencian town of Alboraya, all of which are also underground, or the modern Cercanías halt of the Manuel-Énova bypass of the high-speed line to Levante.
• With regard to modular stations, in 2009 it developed an innovation project taking a small halt in the north of Madrid, Las Zorreras, as a reference. A similar solution was also planned, the predecessor of that of Soto del Henares, for the Las Margaritas-Universidad station, in Getafe, in the southern zone of Madrid. Abroad, in 2011, eight modern modular stations were designed for the Bogotá Western Corridor in Colombia.
• With regard to the renovation of historical stations, we can highlight the design and construction management of the historic façade of Atocha (2012), that of the full renovation of Aranjuez station (2008) currently underway, or the modernisation works in around twenty Catalan stations (2009).
• As well as architecture projects, we can also highlight other services, such as technical assistance for the work of the new La Sagrera-Meridiana commuter station in Barcelona (2010) or the prior feasibility studies for the Belgrade light rail in Serbia, with 25 stations, 10 of them underground; or for the São Paulo commuter network in Brazil, which included the construction of nine stations and the renovation of 65 others.
• With regard to highspeed stations, Ineco has carried out around twenty projects, both in construction management and in drawing up architectural designs: this is the case for the stations of Puente Genil, Camp and Antequera-Santa Ana (2007), that of Vigo-Guixar or the projects in nine other stations of the Galician Atlantic corridor in 2010 (see article). Ineco has also worked in the construction management to adapt stations in the whole network for high speed: Santa Justa in Seville, Sants in Barcelona, Atocha in Madrid, Toledo, Zaragoza, A Coruña, Santiago and Ourense in Galicia, etc., as well as in that of enlargement of the Atocha railway complex and its new AVE terminal, begun in 2010.