Railway Bridges

Affiliates of the SK MOST Groups of Companies conduct operations between Pickets 141 and 462 or between the 14t and 46th kilometer milestones of combined Adler - "Alpika Service route (railway/motorway) (ending at the town of Krasnaya Polyana) The builders' work project area includes 22 railway bridges of the total length of 11.4 km.

The construction began in the 1st quarter of 2009 and it will be completed in the 2nd quarter of 2013.

Nine out of the 22 railway bridges that are under construction on Adler - Krasnaya Polyana route are special class installations (they are over 500-meters long).

 1. Picket140+29: Single-track Railway bridge, 599.2-m long;
 2. Picket175+38: Single-track Railway bridge, 68.5-m long;
 3. Picket189+48: Single-track Railway bridge, 68.5-m long;
 4. Picket193+08: Double-track Railway bridge, 68.5-m long;
 5. Picke204+93: Double-track Railway bridge, 68.5-m long;
 6. Picket210+64: Single-track Railway bridge, 68.5-m long;
 7. Picket219+00: Single-track Railway bridge, 1065.5-m long;
 8. Picket226+45: Single-track Railway bridge, 73.4-m long;
 9. Picket230+13.15: Single-track Railway bridge, 174.2-m long;
 10. Picket293+78: Single-track Railway bridge, 2617.6-m long;
 11. Picket312+21: Single-track Railway bridge, 30.5-m long;

 12. Picket317+15: Single-track Railway bridge, 30.5-m long;
 13. Picke325+11: Double-track Railway bridge, 1067.3-m long;
 14. Picke335+27: Double-track Railway bridge, 562.2-m long;
 15. Picke342+60: Double-track Railway bridge, 557.7-m long;
 16. Picket351+43: Single-track Railway bridge, 837.9-m long;
 17. Picket360+55: Single-track Railway bridge, 410.7-m long;;
 18. Picket365+78: Single-track Railway bridge, 262.6-m long;
 19. Picket374+05: Single-track Railway bridge, 172.9-m long;
 20. Picket388+02: Single-track Railway bridge, 1792.2-m long;
 21. Picket432+25: Single-track Railway bridge, 253.2-m long;
 22. Picket447+22: Double track Railway bridge, 704-m long;

The railway line construction is carried out under challenging geotechnical conditions in the mountainous area. The grades here are as high as up to 40/1000, which is why the majority of railway viaducts of Adler - Krasnaya Polyana route are curvilinear in top view (with a radius of curvature ranging from 600 meters to 1.2 kilometers). In view of these circumstances, the design was based on bridge installations of two types:
 - with beam span structures;
 - with trussed girder spans and with the ballasted track.

The beam length ranges from 18 to 34 meters and the trussed girders are 55 to 110-m long.

The trussed girder span structures have a stiff bottom flange, which allows the structure to be assembled by launching without intermediate supports; erection welding can be used, and sealed movement joints can be provided between the adjacent spans. For the first time in Russia, the builders working on Adler - Krasnaya Polyana route are using a combination bolting and welding assembly method that was developed by specialists with the Giprostroymost, a Moscow-based design institute (railway steel bridge structures have been assembled using bolted joints only without welding until recently). The new assembly method provides a better protection of the span decks against corrosion, which is especially important in humid subtropical environments. High- tensile bolted joints were replaced with welding joints mainly in the structural members of the bridge floor area that are located under the stone bedding, in other words, in the zones that are most vulnerable because of corrosion. The weld quality is examined by the ultrasonic flaw detection, which is conducted as 100% testing instead of random testing.

Bearings manufactured by Maurer are used for steel bridge spans (this technology has not been used in railway construction so far).

The combined route railway bridges were designed bearing in mind the elevated seismicity in the region. The bridge shock absorbers and bearings will hold the span decks attached to the bridge pillars even under the nine-point earthquake.

OJSC STROY-TREST, 11, block 2, Michurinsky prospect, Moscow 119192, Russia

phone: +7 495 787 57 08, fax: +7 495 787 57 01, e-mail: stroytrest@skmost.ru, web: www.skmost.com