Archive for 2011

Active Fire Suppression System Installed on the Pylons of the Bridge to the Russky Island

Friday, December 23rd, 2011

A state-of-the art Russian-made active fire suppression system has been successfully tested and commissioned during construction of the bridge over the Eastern Bosphorus Strait. The system is designed to lift water to the 350-meter elevation.

This system will fight fires using two methods: simply with water and with temperature-treated water. The latter method consumes a minimum quantity of water that is supplied at the temperature of +200°C under the pressure of 100 atmospheres. When water flows through a special spray nozzle at the end of the firefighting monitor a steam cloud with droplets of 10-50 µm in diameter is formed. Water in this state has many of its physical properties changed, and the man-made fog forms a film on the surface that was set on fire to lower the surface temperature to a significant extent.

When conventional firefighting technologies are used, as little as 10% of water is used directly for fire suppression, and the remaining 90% are just wasted. Everything goes the other way around when the temperature-activated water is used for fire suppression: As much as 90% of water is used purposefully and the water is not lost but rather stays in place as a cloud for almost 40 minutes. Therefore the new method consumes 10 times less water when fire is suppressed outdoors and 50-100 times less when fighting fire indoors.

The active fire suppression system has been installed on the right hand leg of M6 Pylon on the Nazimov Peninsula. The bridge builders, jointly with the designers with the Akva-Piro-Alyans Company, installed the special equipment and firefighting monitors on the self-lift shutter structures. With this arrangement, fire could be prevented simultaneously on both pylon legs. The innovative fire suppression system will be installed on M7 Pylon on the Russky Island shortly.

Photo by Igor Lischuk / SK MOST,
Vitalij Ankov / NPO Mostovik

Construction of cable-stayed bridge in Vladivostok – video presentation, november 2011

Tuesday, December 20th, 2011

Lifting Cranes Operate at an Elevation above 300 Meters on the Construction Site of the Bridge to the Russky Island

Tuesday, December 20th, 2011

Potain and Kroll Tower Cranes that are used to erect the giant pylons of the bridge to the Russky Island have been telescoped up to an elevation above 300 meters.

The unique heavy-lift high-rise cranes were ordered specifically for construction of the bridge over the east Bosphorus Strait. They have been telescoped by inserting additional tower sections with the help of hydraulic equipment. The giant cranes have been grown higher to catch up with the pylons to rise above the pylon legs.

The lifting cranes have now grown over 300 meters high for the first time in the Russian bridge building history. Sections No. 65 of M6 Pylon, which is now 292.9-meter high, have been concreted on the Nazimov Peninsula side. Sections No. 63 of M7 Pylon whose legs are now at the elevation of 283.9 meters above the sea level have been completed on the Russky Island side. The lifting crane cabs will finally rise above the Eiffel Tower to become 340-meters high by the time the construction work has been completed.

Photo by Igor Lischuk / SK MOST

Builders of the Bridge over the Eastern Bosphorus Strait Completed the Reinforced Concrete Stiffening Girder on the Mainland Side

Tuesday, December 13th, 2011

The builders of the bridge over the Eastern Bosphorus Strait have completed erection of a 320-meter long section of the prestressed reinforced concrete stiffening girder on the Nazimov Peninsula side. They proceeded with the concreting of the closing section of the bridge anchor pad span ion the Russky Island as well.

The span structure that has a complex and large cross-section between M1-M5 and M7-M12 bridge pillars is constructed of prestressed reinforced concrete. The amount of reinforcement of the stiffening girder on each side of the strait is about 4,000 metric tons with the concreting volume in excess of 10,500 cubic meters. The major work on the mainland side has been completed; the bridge builders have finished with the tensioning of high-tensile reinforcing strands and injected the ducts by filling them up with a special cement mortar under pressure. They have also started the concreting of the closing section in the side span where over 400 cubic meters of high-grade concrete mix out of 1,500 cubic meters as per design have already been lifted to the 70-meter elevation.

Photo by Igor Lischuk / SK MOST