Viaducto de vía estrecha sobre la A-8, Navia. Alternativa al cajón hincado. Tipologías estructurales derivadas

The viaduct heading represents an alternative typology to the well known inserted caisson solution. It presents the realization of an overpass narrow gauge railway, two spans of 26.65 and 27.58 m each, prefabricated deck with pi-beams and side longitudinal banked beams and piers-pile cast in place. It is presented a new construction procedure based on the first embodiment of the piers-pile, the execution of the deck under the railway and the ballast in night operations; transverse post-tensioning in the first instance, and straight longitudinal post-tensioning secondly for the deck; to conclude the controlled excavation below the deck to continue the trunk highway that passes under the structure. In this work new structural types are inferred for the design of similar structures, which are proposed as possibilities for the design of new bridges.