PSI - Issue 84

Michela Briganti Botta et al. / Procedia Structural Integrity 84 (2026) 344–351

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From a work feasibility perspective, considering the interference that the construction site for the new pedestrian walkways would have with railway traffic, it is important that their construction is carried out concurrently with the waterproofing system renovation works. This allows the same temporary suspension window of railway operations, which RFI schedules in relation to the strategic role of the railway line where the structure is located. 2. Projects Sintagma is a design and consulting company leader in the field of transport infrastructures. The company works on the Venice–Trieste railway line. The intervention requested by RFI has become necessary due to significant deterioration of the waterproofing system observed on the Sacile, Barcola and Aurisina viaducts. The structures have shown that the degradation of the existing waterproofing system has caused water infiltration inside the masonry, exposing the works to progressive deterioration which, without corrective measures, would eventually damage the structural components. Barcola viaduct is on the Venice–Trieste railway line and it is located at the entrance to the city of Trieste. The viaduct, built with masonry arches, is approximately 270 m long (from abutment to abutment) and it is divided into 20 spans with a spacing of about 12 m. The spans are grouped into sets of five, separated by combined pier-abutments, for a total of three such units. The structure, dating back to between 1850 and 1860 (the Trieste–Vienna railway line was inaugurated in 1857), is uniform with the typical construction styles of the time found along nearly all similar structures built by the Austro Hungarian Empire. It is built using squared limestone blocks, with architectural projections at the arch’s springers and at the base of the masonry parapets. 2.1. Barcola • Overview and Characteristics

Fig. 2. Barcola – Mountain-side view

The viaduct has an internal width of approximately 9.80 m, originally designed for a double-track line. Today, however, this width is insufficient to allow standard inspection and maintenance operations to be performed safely alongside the tracks. Furthermore, due to the massive masonry parapet (an extension of the tympanum) on the seaward side, the usable railway platform is reduced to about 9.1 m (considering that current standards require more than 12 m). Consequently, RFI needs to install steel walkways to ensure inspection and maintenance activities while respecting safety clearances from the tracks.