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Engineering Projects: Rotonda de Gir a la C.G. núm. 1, Zona Frontera Espanyola

Infrastructure


Place:

Sant Julià de Lòria (Principat d'Andorra)


Date: 2001-2004
Rotonda de Gir a la C.G. núm. 1, Zona Frontera Espanyola, Engineering (Principality of Andorra)

Rotonda de Gir a la C.G. núm. 1, Zona Frontera Espanyola

The immediate background is the project "Roundabout turn in main road No. 1", located between PK 9 +807,913 and PK 9 +878,215 of the current road, near the spanish border in Sant Julia de Loria parish.
 
This project develops like a modified the former respecting all the conditions, but slightly shifting the center of the roundabout towards the city centre of Sant Julia de Loria.

The roundabout allows the change of direction of vehicles a few meters before reaching the border, this was not allowed before. But provides an easy access to private property adjacent to the border area.

However, it has included the lighting project from the Spanish border to the town of Sant Julia de Loria and the replacement of pavements of sidewalks for asphalt concrete pavement although the last is not included in the project.

The roundabout is placed centered on the axis of the Main Rd No. 1 in an area of Spiral with a parameter A=132. The centerpiece of the new platform matches the current axis.
 
The longitudinal gradients ranging from 2.3% on the South and 3.93% on the North.

The inner radius of the roundabout is 10 m and 18 m outside. These eight meters are distributed by 0.85 meters of outer shoulder, 3.15 m of outside lane, 3.65 m from the inside lane and an inside shoulder of 0.35 m.

The inner radius of entry and exit of the roundabout in the sense from  Sant Julia to Border sense are 30,00 m while those associated with the sense- from border to Sant Julia are 40,85 m.
 
The links with the existing road ensure the transition to the type section of the current Main Rd No. 1 with two lanes of 3.15 towards Andorra and one of 3 and another of 3.10 towards Spain.

Both directions of traffic have a shoulder of 0.85 m which facilitates the movement of cyclists.