In the first quarter of the 18th century, along the axis of the current Grivtsov Lane, there was a road leading to Saar Manor or Sarskoye Selo (later Tsarskoye Selo and the city of Pushkin), along which there was a wooden beam bridge over the Glukhaya River (now the Griboedov Canal). On August 20, 1739, the road was named Malaya Saar Street (Sarskaya Street). At the same time, the crossing was named the Small Saar (or Sarsky) Bridge. In 1776, the bridge was rebuilt in wood.
The bridge connects Kazansky and Spassky Islands. The single-span metal bridge that has survived to this day was constructed in 1834–1835 according to the design by engineers E.A. Adam and P.P. Bazen, based on standard drawings by engineer V.I. Geste. The metal arched span structure is made of 91 cast-iron wedge-shaped tubbing sections bolted together. The bridge length is 33 meters, width — 16 meters. The crossing was decorated with an openwork cast-iron railing and four lanterns on cast-iron posts. The metal structures and decorations of the bridge were manufactured at the Alexandrovsky State Cast Iron Foundry in Saint Petersburg. Construction was supervised by engineer E.A. Adam. The bridge opened to traffic in 1835. According to one version, the ornament on the bridge railings was designed by architect A.I. Shtakenshneider.
The bridge abutments are massive, stone, on a pile foundation, faced with granite. The bridge railings are artistic cast-iron grilles, with a pattern resembling fan-shaped palm leaves. On the bridge approaches are granite parapets. The bridge surface is asphalt concrete, and the approaches are paved with granite slabs. At the bridge entrances, four cast-iron torcheres with quadrangular lanterns are installed. The roadway is separated from the sidewalks by a granite curb.
The crossing was named Bankovsky Bridge after the nearby building of the Loan Bank, but this name did not catch on, as there was already a Bankovsky Bridge upstream on the Catherine Canal, built in 1826. The bridge came to be called Demidov Bridge after the lane of the same name, where the plot of mining industrialist A.G. Demidov was located. This lane is now Grivtsov Lane.
The bridge is skewed in plan; its longitudinal axis crosses the Catherine Canal at an angle of 51°.
In 1954-1955, during repairs, restoration work was carried out according to the project of architect A.L. Rotach — the torcheres, lanterns, and railings of the bridge, damaged during the blockade years, were restored.
In 1969, the gilding of the architectural details of the bridge was restored.
In 1988, an elevated granite parapet fence was installed along the roadway.
In 1999, the crossing was reconstructed according to the project of engineer V.V. Zaitsev. During the work, the abutments were repaired, a reinforced concrete relieving arch was installed over the cast-iron part of the bridge, waterproofing and facade sheets of the span structures were replaced, and the railings, torcheres, and lanterns were restored.
The reconstruction was carried out by the trust "Lenmoststroy." At the start of the work, a complete dismantling and concreting of the bridge abutments was planned. However, when the spans were lifted on temporary scaffolding and the upper part of the abutments was dismantled, it was found that they were assembled from massive stone blocks, and dismantling such masonry was very difficult. The builders applied a new technical solution — injection grouting of the rubble masonry of the abutments. For this, holes were drilled through the entire thickness of the masonry, steel reinforcement was inserted, and concrete was pressure-injected. Tests showed that the reinforcement is firmly held in the concrete and cannot be extracted even with a force of 40 tons.
Sources:
https://mostotrest-spb.ru/bridges/demidov
