The Baikal-Amur Mainline (BAM) is the largest railway passing through the territory of Eastern Siberia and the Far East in the direction of Taishet — Sovetskaya Gavan.
The Institute took part in all stages of the BAM design, starting from the pre-war period. When the all-Union construction of the highway began in 1970-1980, Lengiprotrans was instructed to design the Chara — Tynda section. On this site, the institute has designed 798 artificial structures, including 25 large railway bridges and 1 overpass.
A large railway bridge across the Bolshaya Ikabya River was erected at 1151 km of the BAM. Bolshaya Ikabya is a right tributary of the Chara River and flows in the Kalarsky Range in the northern part of the Trans-Baikal Territory. The region is characterized by alternation of high ridges with deep intermontane pits. Difficult climatic, geological and geocryological conditions, the presence of high seismicity, as well as the absence of access roads required a search for non-standard solutions during the work.
The bridge was designed according to the 3x34.2 m scheme with a length of 284.5 m. Metal superstructures with ballast riding on top have been erected. The intermediate supports of the bridge have a prefabricated monolithic structure of contour blocks with concrete filling of the core. The pillars were built on a natural foundation. The structure of the supports was developed by Lengiprotrans in 1980 for widespread use at bridge crossings of the Chara — Tynda section.