The object of this contract is the undertaking of the execution project of the new RN6 roadway, this being, a widening and improvement of the current RN6. The work consists, in its first stage, of the study of the improvement of the route both at base level and on the upper surface, the study of the length and cross drainage and valuation of the different standard sections caused by the variability of the zones it runs through; in a second stage the project is completed with a graphic definition and a valuation of the measurements of each one of the infrastructures designed for the functioning of the roadway.
The section between Zinguinchor – Kolda is divided into two lots. Each one of them is
- Lot no. 1. Ziguinchor to Tanaff Section
- The road runs from Ziguinchor to Tanaff, with a total length of corridor of 116.63 km.
- Lot no. 2. Tanaff to Kolda Section
- The road runs from Tanaff to Kolda, with a total length of corridor of 77 km.
Both sections are located practically parallel to the River Casamance. The main section consists of a platform of two (2) lanes 3.60 m wide and two (2) verges of 1.50 m in width, after which is the slope and the edge of the natural terrain, where the ditches are designed with variable sections.
In the project the transit sections through the villages, and the intersections of tracks which allow entry/ exit to those villages are studied. To this end, two types of intersection have been designed, one with larger dimensions than the others, with location depending on the intensity of traffic.
To discharge water via lengthwise drainage (drainage from the roadworks themselves), different types of ditches have been designed, some of them triangular in cross section in dirt, and others in concrete and square in cross section. To sustain the passing of water crossways, manufactured products have been designed, square in cross section and with interior dimensions from 1×0.80×0.80 to 6×3.00×3.00.
The elements needed for signage and road lighting are also foreseen.
Likewise, the complementary operations needed have been foreseen for the proper finalisation of the work.