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The number of bridges in St Petersburg is still growing because of its position at the mouth of the Neva River with its two arms. Engineer S. Kerbedz and architect K. Brulov spanned one of arms in 1850 by remarkable engineering work. It was the Blagoveshchensky (Annunciation Day) Bridge. In 1918 the bridge was named after Lieutenant Schmidt, (fig. 5.1; 5.2e), a hero of the 1905 revolution, but now it bears its original name. This is the oldest permanent bridge and the last one before the Neva flows into the Gulf of Finland. At the beginning of the 20th century, it appeared to be too narrow for traffic and impassable for navigation. Professor G. Peredery designed a wide seven-span structure in 1938. Now the total bridge span is 331 m, and its modern movable span gives access to ocean vessels of 50-60 m in height. It was the first time that engineers had pioneered electric welding instead of riveting for such heavy metal structures.
Engineer A. Struve and architect Ts. Cavos designed the Liteiny Bridge. Constructed in 1879, it was the first bridge illuminated by electrical lights along its total length of 408 m (fig. 5.1). The old structure could not respond to modern traffic demands, and its steel arches corroded. The reconstruction of 1967 preserved its original form because steel girders remained on the reconstructed piers. Its bascule leaf holds the world record for its length and weight of 3,225 tons. Powerful hydraulic devices can lift it within two minutes. The bridge features highly artistic wrought iron railings adorned with Russian State Emblems.
The celebration of the 100th Anniversary of St Petersburg’s foundation followed by the international competition for the best bridge design. The idea of a cantilever arch structure, put forward by French engineers, prevailed, and the Trinity Bridge was built nearby the Summer Garden in 1903 (fig. 5.1; 5.2f). The Neva River is very wide at this place so that the bridge with its flat metal arches is 582 m long, and its bascule span allows free shipping.
The next competition was announced for the Palace Bridge construction close to St Basil Spit (fig. 5.1; 5.2g). The expert commission adopted a five-span structure with sculptural decoration in classical style, but the First World War cancelled that plan, and the bridge designed by A. Pshenitsky in strict monumental style appeared in 1916. Its total length is 250 m, and the 57 m steel bascule span, directed towards the pale sky during the “white nights”, looks very romantic.
It was no easy task to connect the soft riverbanks of the Neva River. However, innovative building technology provided suitable solutions. Professor G. Peredery and architect A. Nickolsky designed the Volodarsky Bridge (fig. 5.1) which was open to traffic in 1936. The bascule, double-leaf middle span is made of metal. Its steel tubes filled with concrete served as arch reinforcement and could resist large compression forces. The reinforced elements look as if they were entirely made of metal, and the concrete river piers are faced with granite. There are bascule span mechanisms inside the piers. The length of each of the two river spans, supported by flat arches, is 101 m. The arches have no wind bracing and the piers do not have cutwaters.
The total length of St Petersburg’s bridges is nearly sixteen kilometers, and the Alexander Nevsky Bridge is one of the longest and widest amongst them. Its overall length is more than 900 m including approach ramps, and the width is 35 m. The bridge was open in 1965. It represents a typical engineering structure from the second half of the last century, looking strict and in harmony with its surroundings (fig. 5.1). However, the record holder among the bridges across the Neva River is the Big Obukhovsky Bridge that is 2,824 m long (fig. 5.1; 5.2h).
The Big Okhta Bridge is of a through type. Designed by engineer G. Krivoshein, it started its service life in 1911 (fig. 5.1). The total bridge span is 355 m. N. Belelyubsky and G. Krivoshein designed the Finlyandsky Railway Bridge. That through bridge was open nearly a century ago, in 1911.
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