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Advert pages 24/3/03 12:22 pm Page 22 pp23-30 Contract 3 Loranca 24/3/03 12:30 pm Page 23 CONTRACT 3 Contract 3 Section IV, Sub-Sections III-B, IV-A & IV-B Contractors: Loranca to Fuenlabrada in Cut and Cover Construction of sub-sections III-B and IV-A of Contract 3 was awarded to the contractor Sacyr, for a total initial budget of €21,819,480 and an initial term of 15 months; sub-section IV-B was awarded to OHL, for €39,123,152, to be completed in 20 months. Section 4 is unique within the Metrosur project, because it was built entirely without a tunnelling machine, giving it some very special character- istics. A variety of three or four differ- ent tunnel faces could be open at any one time, as opposed to the single- face tunnel type. This provided enhanced flexibility for unforeseen circumstances, and made it possible in one tunnel to offset delays at another, or accelerate progress by opening new faces. Project Alignment Another feature of Section 4 is the disconti- nuity in the construction methods used, adapting to the peculiar conditions of the track crossovers necessary at Loranca Loranca station and tunnel. This resulted in six changes over station, in order to handle the rolling stock. surroundings, looking towards 2,400 m of tunnel. Such compartmental- Section 4 is situated on the Fuenlabrada- Fuenlabrada Hospital. ization required activity and connection Móstoles axis, to the south side of the times to be co-ordinated but, by the divi- Metrosur ring. This axis is in an area where sion of work, also allowed any scheduling the existing major communication routes error accumulated over the section to be are radial: four are highways (M-409, M- better controlled. In particular, sub-section 407, R-5 and Avda. Móstoles), two are rail III-B contains 275 m of diaphragm-walled (the C5 commuter line); whilst two are tunnel and Loranca station; sub-sector IV-A orbital (the M-506 and M-50 highways). has 413 m of tunnel using traditional The Fuenlabrada-Móstoles axis, there- methods; and sub-sector IV-B has 270 m of fore, provides a balance for the communi- diaphragm-walled tunnel, 1,273 m of cation system, offering a rail transverse to open-cut tunnel, and Fuenlabrada Hospital relieve pressure on the radial routes, and (F2) station. opening up other Metrosur line possibilities. The contract work location is close to the The III-B and IV-A sub-sectors are located Metrosur train sheds, making two diagonal in the Loranca housing development, a METROSUR 2 23 Advert pages 24/3/03 12:23 pm Page 24 24 METROSUR 2 pp23-30 Contract 3 Loranca 24/3/03 12:30 pm Page 25 CONTRACT 3 satellite residential neighbourhood of Fuenlabrada on the municipal border with Móstoles. Sub-sector III-B runs through a major area of services in the heart of the neighbourhood, while IV-A runs through the oldest part. Sub-sector IV-B links the Loranca hous- ing estate with the urban centre of Fuenlabrada, in an area that is currently open country. A hospital and university are now being built there, and further urban development projects are imminent. Station Areas Traditional tunnel from Loranca station. The station spaces must accommodate the service elements required, conducive to the such as journalism, advertising and public special features of the surroundings. relations, telecommunications engineering, Loranca (F1) station is located on an open and audio-visual communication; a 400-bed space bordered by parks and gardens in the hospital with 68,000 sq m of buildings. South, extending into Calle Pablo Iglesias For access to the University, a passenger with a wide landscaped median, and, on the escalator shaft has been designed and con- North side, an adjacent service area. structed to run under Camino del Molino, The architectural details are notable: a so reducing interference between traffic and health centre with a central module in the pedestrians. The shaft runs oblique to the shape of a truncated cone; the District station, and has a portal for a perfect exit to Council offices with a glazed frontage; and a the footpath around the university land. two-level shopping mall. Between these ele- The hospital exit was moved to the ments, there is a square giving access to the south side to emerge outside the hospital northern station shaft, where the paving fence. This required creation of a new and fittings planned are for pedestrian use. enclosure at the vestibule level, at the con- Accessibility is very good, with platforms nection point between the two passenger some 14 m below the surface. Passenger shafts. This enclosure incorporates a lift, to shafts are arranged for quick and easy reduce surface area, at a point where a access to the commercial service area on hospital entrance has been planned. the one hand, and Calle Pablo Iglesias on The work was thus adapted to the sur- the other. The dimensions of the station roundings, in co-ordination with the halls are limited, because of their proximity Fuenlabrada Municipal Corporation and to the mall. Their metal and glazed struc- the technical teams for the various activities ture fits perfectly into the square’s architec- involved. The station is perfectly adapted tural surroundings. to future requirements, ready to serve Although sub-section IV-B ran through students, health service users, and residents open country at the time of construction, in the urban developments planned in the the surrounding conditions were as deci- adjoining zone. sive as if this had been consolidated urban land, or more so. This was not just because Future Station the proposed developments had to be Future station between F1 and respected: the fact that they were not Of the housing developments in the area, F2 to serve proposed housing defined or exactly located prevented deci- the first covers 52.2 hectares and contains development. sion-making and, in many cases, affected the rate and distribution of the work. Fuenlabrada Hospital These circumstances became more patent at the Fuenlabrada Hospital (F2) station, where three urban schemes converged: the hospital, the university and development for residential and sporting uses. The station environment is therefore an important centre of educational and health services including: a high school for 1,100 pupils, 2.3 hectares of land and 5,000 sq m of buildings; the King Juan Carlos I University for 4,000 students, about 50 hectares of land, and with six units now built. A variety of disciplines are taught here, METROSUR 2 25 pp23-30 Contract 3 Loranca 24/3/03 12:30 pm Page 26 CONTRACT 3 The procedure was as usual: surface preparation; building a low guide wall before construction of the side diaphragm walls; excavation between the walls to the lower level of the upper slab; removal of tops of the diaphragm walls; installation of the top slab including its tie beam; excava- tion under the slab; finally, casting the invert on the exposed ground. In this case, excavation was mostly by access from the upper level, driving down the station ramp, and the remainder from the station invert level, with the spoil removed along the tunnel access ramp. Performance can be assessed using the criterion of area of diaphragm wall con- structed per month. In the first four months, 97.4% was built, at a monthly average of 2,096 sq m, and a maximum of 4,064 sq m. On the other hand, the presence of gas and tele- phone utility service lines led to delays in completion of the diaphram walls. For nine Open cut tunnel under 1,850 single and grouped family homes, months the sidewalls had to be built by construction. 58,000 sq m of ‘green belt’, and 46,000 sq m underpinning from inside the excavation. for public facilities. There will be a large Built between diaphragm screen-walls, sports complex, and the Fregacedos the central box of the sub-section III-B sta- lagoon is to be restored, to form part of a tion has pre-stressed beams 29.6 m-long large public park. On the other side of the and 1.85 m-high. The top slab was assem- tunnel route, a second development is to bled on site from pre-fabricated slabs. The be built, on 26 hectares, with 750 homes other upper and vestibule slabs are light- and 55,000 sq m of ‘green belt’. weight. Also accommodated are an elec- To provide a transport service for this tricity substation with load-bearing slabbing future demand, in the hub of the two at the bottom of the cable floor, and eight housing developments, a ‘first’ tunnel pile-piers supporting the vestibule. enclosure was built, with the dimensions The station perimeter is a 12-sided poly- and elements necessary to facilitate later gon, so that progress was less than that for construction of a station. It is 120 m-long the tunnel: an average of 1,843 sq m/ in a straight line, with a width between month in the first four months, and a maxi- gable walls of 8.6 m, and a removable mum of 2,800 sq m/month. Completion of vault section formed by prefabricated slabs the northern passenger shaft created a on geotextile-covered metal trusses. minor schdule delay. The area is designed for the incorporation The sub-section IV-A tunnel begins in of perimeter screens around the future sta- Loranca station, and is cut by the access tion, interior excavation, removal of the ramp at 70 m on the right.

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