Durability of Cycle-Pedestrian Glulam Bridges and Footbridges: Research onto Good Design and Maintenance Practices

In the early 2000s, experimental research was carried out at the DICA (later merged into the DPIA) of the University of Udine on the subject of the durability of cycle-pedestrian glulam bridges and footbridges. The contribution reports the main results of that research together with the progress of a subsequent investigation on the same subject that is still in progress. The analysis of a series of works located in the Friuli and Veneto Regions in different climatic and environmental situations had been summarised in analytical sheets, identifying the parts of the structures most subject to degradation, while defining some general principles (guidelines) for design choices and a series of technological solutions considered valid for limiting degradation pathologies. Almost twenty years later, a re-examination of the documentary material produced at the time was carried out in order to critically re-read it. The evolution of pathological phenomena was thus verified in relation to the type of technological solution and, where possible, also to the type and regularity of maintenance. The durability of the technological component was then evaluated, correlating for the individual nodes the system of combinations between their material, constructional and functional characteristics and their conformation/location in relation to their behaviour with respect to external agents. Considering the solutions with the highest score, an abacus of the construction details that have proven to be particularly effective with respect to durability requirements, as well as generally functional for a correct global solution of the technological node, is being created. The monitoring of the footbridges built in the early 2000s showed how the degradation processes heavily affected the construction heritage in question.