ABSTRACT
The aim of this article is to describe the engineering approach followed in the design phase of the Saudi Landbridge Railway Project, applying the best international practice for tunnel design in a non-conventional environment. The alignment has been designed in order to fully comply with the specific functional and technical requirement requested by the Client. To this purpose, a systematic socio economical and cost-benefit analysis has been studied to identify the most suitable civil work, including tunnel, for the optimization of the railway line. Furthermore, due to the presence of extreme environmental condition characterized by desert and dune area, specific sand mitigation solutions have been studied. Specifically for the design of cut & cover tunnels in dune area, non-conventional topics have been addressed, such as the variation of the asymmetrical load distribution due to the dunes displacement or the need to prevent the entrance of the sand into the tunnel.
