Upgrade of the national road RN43, Algeria

Upgrade of the national road RN43, Algeria

Excerpt

The RN43 is to be modernised to attract tourism on the Algerian coast. Comprehensive widening is to be undertaken over the entire length and a new tunnel is to be constructed.

The whole length of the road runs along a coastal cliff with some vertical or overhanging cuttings. Options studies were undertaken for two tunnels and the tunnel portals moved away from the geologically unfavourable weathered breccia slopes. The studies also optimised the tunnel alignments. The tunnel works comprise 880m-long T1, 635m-long T2, 268m-long T3 and emergency escape tunnels 137m-long E1 and 145m-long E2. The project area lies in heavily karsified limestone and areas of block breccia lie along the existing road. Near the end of the alignment there are folded clay and siltstones.