The engineering design of the Tua rail track : evidence from the archives

摘要

This paper intends to give a detailed overview of the different phases of the Tualine focused on the changes in the longitudinal and transversal outline and onthe definition of the project of special structures (tunnels, bridges, aqueductsand stone walls). For this, a detailed investigation was carried on the archives ofREFER, the company in charge of the management of the infrastructure of thenational Portuguese railways. The Tua line fit the Nacional railways plan, definingthe connection between the Douro region in Foz Tua and Mirandela in a first phase(1987) and Bragança in a second phase (1906). The construction of the Tua lineaimed at flowing the products derived from the Douro region. Its construction wasnot an easy process, mainly in the first 20km due to the severe relief, composedof narrow valleys with impressive ravines, precipices and waterfalls. This difficultywas also associated to the lack of accessibilities and to the scarce technologicalresources, resulting in several accidents and human losses and to a huge physicaleffort. The first studies related with the Tua line date back to 1880 and the last onesare from 1883. However, due to changes imposed by the in situ geomorphologicalconditions, amendments to the project were made and presented in 1885. Severalchanges are identified between the previous studies, the project and rectified project.