Railways

The choice of the tunnel system for modern railway tunnels depends on a variety of factors, including traffic composition and traffic volume, cost, maintenance and safety. They are equipped with ventilation systems, slab tracks for higher operating speeds, smoke extractions systems, etc.

Technology applied in underground construction has advanced significantly in the past decades making challenging geological subsoil conditions feasible to deal with.

Railway tunnels built more than one hundred years ago as pioneering achievements struggle to comply with the present regulations and standards. This inevitably leads to the necessity to refurbish these to ensure these structures remain in service. Also impacting the continued use of existing tunnel structures are new or different rolling stock which may demand higher clearance profiles, as well as implementation of higher standards for passenger rescue and evacuation. Last but not last logistics solution are necessary to ensure traffic is maintained during the works avoiding significant impact on the public and the environment.