Final construction section started at Saaletal viaduct

60 metres high, 1.2 kilometres long and comprising 15 spans with varying span widths: the new Saaletal Viaduct will be a bridge of superlatives. Not only its size and height are challenging but also that it doesn’t run in a straight line but in a long arch through the valley and that is has a steep incline from north to south (height difference of around 60 metres). The bridge is part of the new town bypass Bad Kösen which mostly relieves the spa town from through-traffic from national road B87. The new 13.6-kilometre-long section comprises in total seven bridges. The largest and most impressive of them being the Saaletal Viaduct. It is erected within a nature reserve over river Saale as well as two train tracks. Due to the special conditions, a hybrid construction method was chosen. The northern and southern ramp structures are built by reinforced concrete composite method. The prefabricated steel elements were pre-mounted at an assembly yard, welded and subsequently incrementally launched during six launching operations starting at the northern abutment as well as the southern abutment. Afterwards, the steel elements are completed by a reinforced concrete slab to form a steel composite cross section. The structure over river Saale (span width 130 m) and the cantilever areas until the coupling points with each steel composite superstructure (each around 100 metres) are erected by cantilever method as prestressed concrete superstructures. The semi-integral structure is founded on all axes on deep foundations (bored pile lengths up to 35 m). The construction site is rapidly advancing: Currently, the composite deck slabs are concreted in weekly sections by formwork travellers which work in parallel at the norther and southern construction fields. Simultaneously, the prestressed concrete section at axis 90 is gradually completed so that the superstructures “approach” each other bit by bit. Moreover, two temporary steel supports are mounted which are required at the northern and southern coupling points. If everything goes according to plan, the coupling points over river Saale (prestressed concrete – prestressed concrete) and the northern as well as southern “hybrid” coupling points (prestressed concrete – steel composite) will be constructed in November 2024. SSF Ingenieure in joint venture with engineering office IBV signs responsible for on-site construction supervision and safety and health coordination.