OREANDA-NEWS. The SK MOST Group of Companies has been working on an underpass in the city of Pavlovsky Posad, Moscow Region. Repair work on two bridges over the Vokhonka River nears completion, and preparations to building the major facility, the railway underpass, are underway.

Protective screens are being built, which will function as retaining walls to enclose the future underpass construction site against soil collapse and to prevent the railway tracks from being deformed. Each retaining wall consists of eleven 820-mm diameter pipes, each 20 meters long.

The pipes are driven through the railway embankment by using a custom-built machine that was designed and fabricated by engineers of the SK MOST Group of Companies. The machine has a work platform, which supports a rotary drive of an auger having a drill bit and has a hydraulic jack. The machine loosens the soil and drives four-meter-long metal pipe sections through the soil within the driving zone.

A novel feature of this known process is the use of the HЁ№nnebeck climbing formwork components for vertically moving the work platform. This setup was used for concreting the pylon of the bridge over the Eastern Bosphorus Strait in Vladivostok.

There are two hoisting gears of this type installed in the construction site pit, and they allow the work to be done in an alternating fashion so that the pipes that have been driven in place can be concreted without construction downtime.

This method for raising the tube-driving machine substantially accelerates and facilitates the construction of the protective screen by microtunneling. The work is carried out with the trains, including high-speed trains, rolling without interruption.