Designed by Russian company Mostovik, and built by Russian general contractor USK Most, who subcontracted the construction to its subsidiary SK Most and Mostovik, the Russky Island Bridge will have a total length of 1,872 metres. It is made up of a 28-metre wide central span, two A-frame towers 320 metres high, 168 parallel strand stay cables and dampers placed on each of these stay cables. Freyssinet carried out the design, production and installation of the stay cables on the structure, as well as positioning the dampers. Furthermore, Freyssinet conducted an expert appraisal on behalf of the Russian Ministry of Construction to validate the solutions selected for the design of the structure.
Compact, parallel strand stay cables to minimise the effects of the wind For the Freyssinet team responsible for installing the stay cables and dampers, everything started in July 2011 with the positioning of the first pair of stay cables at a height of 186 metres. From that date on, the operations proceeded with the installation of the 8 planes of 21 stay cables as the bridge was built, with a total of 3,700 tonnes of strands! Due to the exceptional length of the stay cables (the longest being 582 metres, another record), Freyssinet developed individually-protected parallel strand stay cables to minimise the effects of the wind on the structure. These “compact” stay cables feature a greater number of strands, which allows the outer sheath to be saturated (approximately 20% more strands in relation to a sheath of the same diameter). The outsides of the sheaths are also fitted with helical ribs to prevent vibrations resulting from the combined effect of wind and rain. Individually anchored by wedges on upper and lower blocks arranged in the towers and in the deck, the strands and all the stay cable bridge components have a service life of 100 years. Dampers adapted to the size of the bridge Since 25 March and the positioning of the last stay cables, Freyssinet has been focusing on installing the dampers. These dampers, developed and patented by Freyssinet, are external for the longest stay cables and internal for the shortest ones. Furthermore, the longest stay cables installed on the central span are equipped with magnetorheological dampers, the viscosity of which is adjusted electrically in line with the vibration frequency (Maurer technology). The finishing work, which also benefits from Freyssinet innovations, is next in line. Golden Horn, Vladivostok’s second bridge Just 5 kilometres from the Russky Island Bridge, Freyssinet has also designed, supplied and installed 192 stay cables for the Golden Horn Bridge. Located in the heart of Vladivostok, this cable stay bridge connects the northern and southern parts of the city. With a span of 737 metres (and a total length of 1,389 metres), it will be the 10th largest cable-stayed structure in the world when it opens.