The Project consists, in essence, of the extension of the current GC-1 motorway, which links the capital of the island of Gran Canaria with the tourist zones to the south-west, with a length of 6.25 km. It is particularly noteworthy because 70% of the motorway runs underground through the four tunnels making up the route, Candelaria, Tauro, Taurito and Mogán. The section will have a dual carriageway with two 3.5 metre lanes in each direction and a median of varying width.
It also has two viaducts in the Tauro and Mogán Ravines and four underpasses in the Lechugal and Taurito Ravines, needed to establish the junctions to interconnect the new route with the main tourist centres in the zone.
Modified Project No. 2 arises from the need to gather together the circumstances which have appeared since the start and needs for action applicable to Modified Project No. 1:
Safety prevention need against rockfalls on the road, by increasing the length of the artificial tunnels and stabilising the potentially unstable slopes of dismounted material.
- New studies have been carried out during the execution of the work to analyse the possibility that rockfalls may occur on this branch road. To this end a series of simulations have been performed which have led to the establishment of safety measures to minimise the effect of the falls; the simulations have shown the need to increase the length of the false tunnel foreseen for the entrance to the Taurito Tunnel, making it necessary to place infill on this to absorb the possible rockfalls in order to conserve the safety of the road.
- Considering the geotechnical parameters of the material actually found, the foundations conditions were determining with recalculation of all the false tunnels.
- Given the nature of the materials found during the execution of the excavation in part of the dismounting of the hillside which borders the GC-200 in the zone affected by the works, protection or stabilisation of the materials becomes clearly necessary to preserve the safety of this road.
Environmental adaptation of the authorised Candelaria dump, guaranteeing its stability for the execution of a rockfill wall in the slope of the ravine course, a hard shoulder fit for traffic and a network of surface drainage.
- In the face of the possible carry-off effect of rainfall on the material deposited in the Authorised Candelaria Ravine Dump and the consequences this could have for the burying of the Overflow Drainage Tube, the Island Waters Council requests the building of a rockfill wall at the foot of the dump to protect the course, and the building of an access track to the bottom of the ravine for the dump.
Need to protect the foundations of the Tauro and Mogán viaducts and guarantee safety against flooding by means of the channelling of the Tauro and Mogán ravines following the recommendations which the GRAN CANARIA ISLAND WATER COUNCIL requested.
- Given that both in the Mogán and in the Tauro Ravine, foundation elements have been put in place for the viaducts in the surface of the public channel, the Island Water Council considers that there is need to execute open channelling which will allow the flow to discharge overflow and adapt to the particularities of the existing courses.
Evacuation of the surges appearing in the tunnels by the execution of drains and their waterproofing.
- Due to the massive influx of water in the Mogán Tunnel, a drainage system has to be designed which catches the water and takes it out of the tunnel in order to preserve the stability of the cavity and protect the set of road surfaces from possible seepages. The system comprises a draining trench at the foot of the side walls and of waterproofing of the vault by means of Carfoam type sheet coating.
Inclusion of requests made by the Official Organisms with regard to safety, exploitation and maintenance requested by the City Council of Gran Canaria, and channelling of a pipeline in the tunnel as requested by Directorate General for Water of the Government of the Canary Islands.
- Therefore, an adjustment is carried out in the tunnels section for the inclusion of the channels needed, in particular to enable the execution of a concrete conduit with covers which would house a 400 mm tube.
- Inclusion of the requests made by the City Council of Gran Canaria to undertake correct exploitation of the section, in particular with regard to enlargement of the control centre, which is vital to meet Health and Safety regulations for the personnel assigned to that centre.
The need to ensure the Cura Ravine housing development against vibrations and rockfalls.
- It is deemed necessary to protect some of the buildings located in the Cura Ravine by means of a dynamic barrier, as well as a previous cleaning up of certain zones on the hillsides where there are materials whose stability could be compromised during the construction of the Taurito Tunnel.
Adjustment in the definition and budget proposal for all the tunnel facilities once their exact length has been defined, in particular the lighting, with consideration also of the current regulation in force. A definition is also made of the electrical connections and the transport of medium tension in accordance with the real availability the supply company has in the zone where the work is taking place.
Likewise other lesser modifications have been undertaken, among which, to be stressed, are:
- Adjustment of measurements performed in excavations and concrete in tunnels, considering the line of supply.
- Change in the type of road surface for the top wearing course (AC-16 surf B60/70), maintaining the section adopted.
- Improvement in the environmental integration, changing the type of walls of the reinforced walls of the Mogán junction, for gravity walls with rock infill, thus achieving better blending with the setting.
- Updating of the replacements of the services affected known to date.
- Updating of all the measurements known at the date of drawing up Modification No. 2.
Types of service provided
- Drafting project designs
- Road Works
- Tunnel Works
- Viaduct Works
- Drainage Works
- Electrical Installation Works (LT and HT) Public Lighting Works
- Installations in Tunnels Works
- Fire Prevention System Works
- Landscape and Gardening Treatment Works
- Replacement of Overhead and Underground Electrical Network in High Tension
- Replacement of Domestic and Irrigation Water Supply Networks
- Replacement of Sewage Networks
- Replacement of Telephony Networks