Komsomolsk-on-Amur road-rail bridge

In the period from June to September 1932, the first survey of the bridge across the Amur River on the future Baikal-Amur Mainline was conducted around the city of Komsomolsk-on-Amur, being under construction then. An exploration team of experts from the Institute Lengiprotransmost offered three main options of the crossing up to the village of Pivan' within the future city: above, below and within the city limits.

Before the bridge was opened for traffic, a regular ferry service had operated. After the opening of the railway line Khabarovsk — Komsomolsk-on-Amur — Sovetskaya Gavan, the automobiles had to cross the Amur River by railway ferries: Project 723, Volga (until 1952 — The ferry number 1), Don (until 1952 — The ferry number 2), Amur and Komsomolsk.[1][2]

During the winter months, ice was additionally frozen, and crossing was possible along temporary rails over ice. Since 1961, the ferries were led by icebreakers to extend navigation in autumn and winter.

Construction of the bridge started in 1969. In October 1974, the last pier was erected — as there were nine in number. The installation of the last span was finished on 1 August 1975.

On 26 September 1975, the main bridge of the Baikal-Amur Mainline was solemnly opened to rail traffic. At midday, a passenger train from the station of Komsomolsk-on-Amur reached the first portal of the new bridge. The ferries that had operated here for more than 30 years said goodbye to Amur by emitting a series of long beeps.

A project for the future bridge was developed in 1970 by the Design Institute "Lengiprotransmost" (LGTM) at the request of the USSR Transport Construction Ministry.

The span structures of the bridge were designed for class S-14 loads, while the two-lane highway ― for class NC-80 and N-30 loads in compliance with current technical rules and building codes. The bridge's steelwork elements were designed for arctic service in the zone A.

The construction works were carried out by the Komsomolsk work team MO-26 of the trust "Mostostroy-8". In fact, two spans of the single-rail track and two-lane highway are resting on the common ferro-concrete piers. The spans of the two-lane highway are fixed in the outboard supports (on the downstream side).

The total length of the bridge, including approaches from abutment to abutment, was 1,435.32 metres. The height above the water edge was 24 metres. A catchment area was 1,730,000 km².

The Amur River Bridge

The bridge with the 220 kV-powerline installed on it

During construction in the period 1970-1971, a method of Prof. Konstantin Silin (1913–1996) was used for the first time in domestic practice of bridge building for erecting piers on the foundations of ferro-concrete sheaths with a diameter of 3 metres that excluded the use of the caissons that had been traditionally used in the construction of large and road-rail bridges of the Trans-Siberian railway.

For anchoring the ferro-concrete sheaths into the bedrock, the reactive turbo-drilling method was applied for the first time in the world practice of bridge building. For this, a reactive turbodrilling machine of RTB-600 series was used. It consisted of three turbodrills for providing rotation of a rock-cutting tool in the form of roller cones.

After immersion to the design elevation, the sheaths were filled with concrete by the tremie method. Next, the sheaths were combined by a reinforced concrete slab with the use of sheet piling, on which a pier's body was set in.

The foundations of intermediate supports were manufactured of ferro-concrete sheaths with a diameter of 3 metres to a unified design by "Lengiprotransmost" with the use of concrete of Class М400 (B30) on durability and of Class F300 — on frost resistance, filled with underwater hydraulic monolithic concrete of Class M200 (B15). Reinforcing cages of rebar with a strength grade up to A-I and A-II (St5sp and St3sp steel grades) in diameter of 10 to 20 mm were embedded into the sheaths voids. In total, 304 sheaths were immersed during construction.

The intermediate supports were massive prefabricated monolithic structures. They were dressed with granite slabs from the edges of the foundations up to the high-water level area and equipped with pointed ends on the upstream side serving as cutwaters (starlings) equipped with a vertical cutting surface. The bridge's sandstone masonry piers were quarried from the Kiesovsky and Trikratninsky deposits.

The bridge has become an important nodal point of the Baikal-Amur Mainline and a strategic-military objective. There are barbed wire entanglements into different rows, pillboxes, control towers on the left and right river banks near the bridge. Pedestrians and bicycles are forbidden on the bridge (other than in an organized column). There was also a military unit on the left bank at one time that had a reduced copy of the bridge used for exercises.

• Khabarovsk Bridge
• Trans-Siberian Railway