Étude Avant-Projet détailler (APD) de la nouvelle ligne Ferroviaire Béchar — Gara Djebilet (Tindouf) sous tronçon PK 740+000 au PK 750+000

Abstract

This Master’s thesis delivers a comprehensive Detailed Avant-Projet Study (APD) of the PK 740+000 to PK 750+000 section of the new strategic railway line connecting Béchar to Gara Djebilet (Tindouf). The primary objective of this mining and transport infrastructure is to open up the region and facilitate the large-scale hauling of iron ore. Focused on Materials and Civil Engineering infrastructure, this work details the rigorous structural design of the track superstructure (rails, sleepers, ballast) and substructure layers, alongside the geotechnical evaluation of earthworks in a harsh desert environment. The design framework integrates international technical specifications (such as UIC 719 R and 720 R leaflets, EN 13674, and EN 13230 standards) tailored to the extreme climatic and geomorphological constraints of the Algerian Sahara, notably severe temperature fluctuations and sand encroachment risks. The adopted methodology encompasses the geometric structural design (horizontal alignment and vertical profile), the mechanical stress analysis under heavy axle loads typical of heavy- haul freight trains, and the characterization of local eco-materials for the subgrade layers. The findings validate the structural selection of track components (Continuously Welded Rails - CWR, prestressed concrete sleepers) and optimize the thickness of the sub-ballast and capping layers to prevent deformation and ensure long-term track stability. Ultimately, this study provides a robust technical framework for the sustainable construction of this crucial national railway corridor.