Archive for February, 2012

Bridge to the Russky Island Has Satellite Monitoring System

Monday, February 27th, 2012

The builders of the bridge over the Eastern Bosphorus Strait have completed deployment of a geodetic and meteorological monitoring system that will carry out comprehensive health monitoring of the giant installation using both the GLONASS and GPS global satellite positioning systems.

The pylons, installation units, and the main steel stiffening girder have 2 base reference stations, 6 meteorological stations and 24 global positioning receivers installed on them. The GLONASS and GPS receivers are streaming continuously the reference point positioning data to the Monitoring Control Center where the data is saved and where it is available for the analysis of the bridge health. The data from wind and temperature transmitters, which is also fed to the system, is used to include the wind and temperature effects on the bridge structures.

The geodetic equipment supplied by Leica Geosystems, Switzerland, and the meteorological stations from Vaisala, a Finnish company, monitor displacements of the bridge structures with an accuracy to a few millimeters at points where it is very hard if possible to use the conventional survey methods.

“The importance of installation of the satellite positioning receivers on the edges of the steel stiffening girder is hard to overestimate now. Because the central span deck structure is to be closed shortly, it has become critical for the bridge builders to monitor behavior of the cantilevered parts of the span structure on the Nazimov Peninsula side and on the Russky Island side for the nearest future,” underscores Aleksey Baranov, Director of the OJSC USK MOST Branch in Vladivostok.

“In order to do that, the transmitters will be repositioned from time to time to the next installed panels until the channel span deck is closed. After the bridge has been put in service, the integrated monitoring system will combine a structural health monitoring system, an automated traffic control system, and a security protection system.”

Photo by Igor Lischuk / SK MOST

M6 Pylon of the Bridge to the Russky Island is Practically 320-meter High

Friday, February 17th, 2012

The builders of the bridge over the Eastern Bosphorus Strait have done with concreting of the main structure of M6 Pylon on the Nazimov Peninsula side. It will take to concrete one concrete pouring section to reach the 320-meter height of the structure.

“After the 71st concrete pouring cycle, we can say that the standard-size concreting sections forming the pylon body have been completed. The final phase is to tie up the two pylon legs by means of reinforce concrete cross-pieces at the level of the 71st sections to impart stiffness to the entire structure. The legs will be then capped with concrete “lids” each 80-cm thick, which will support 4.15-meter high tetrahedral pyramids made as the 72nd concreting sections. They will finish the architectural concept of the main bridge support. We are planning to complete the work by the end of February, and the total concrete volume will be 150 cubic meters,” commented Valery Medvedev, Chief Engineer, “Bosfor Department, NPO Mostovik.”M6 Pylon erection started in February 2010. Therefore, it took us exactly two years to reach the 320-meter height.”

Photo by Igor Lischuk / SK MOST

Builders of the Bridge to the Russky Island Proceed with Installation of Stay Cables Longer than 500 Meters

Tuesday, February 14th, 2012

The first pair of stay cables of the bridge over the Eastern Bosphorus Strait, which are longer than 500 meters, was installed in the channel span. A total of 138 stay cables with a total length of 40 kilometers have been already installed on both sides of the strait.

The bridge builders have completed the tensioning of the 36th pair of white-colored stay cables on the Nazimov Peninsula side. Each stay cable is 507.2-meters long. Preparations are underway on the Russky Island side for installation of the 34th pair of stay cables that are 483-meters long. The total length of the stay cables that have been already installed on the bridge over the Bosphorus Strait is about 40 kilometers, and the closing 42nd pairs in the channel span will break the world bridge building record: they will be 580-meters long.

Construction of the giant pylons is almost in the closing phase on both sides of the strait. The height of the main bridge pylon, M6, on the Nazimov Peninsula is now 315.4 meters after sections No. 70 have been concreted. It will take to concrete sections No. 71, which will tie up the left and right legs of the pylon together, and the final section No. 72 to complete construction. There are four sections left to reach the design elevation on the Russky Island: after sections No. 68 have been concreted, the legs of giant pylon M7 are now at the elevation of 306.4 meters above the sea level.

Photo by Igor Lischuk / SK MOST

900 Meters of the Channel Span Deck Installed in the Bridge over the Eastern Bosphorus

Monday, February 13th, 2012

The main steel stiffening girder of the bridge over the Eastern Bosphorus Strait in Vladivostok has come to the 900-meters milestone on February 6 after channel span deck paired panel number 41-42 has been lifted to the 70-meter elevation from the strait water on the Russky Island side.

As a result of this operation, the assembled cantilevered part of the steel stiffening girder on the Russky Island side extends now over a distance of 438 meters from the M7 Pylon centerline toward the mainland. A total of 462 meters of the span deck have been installed on the Nazimov Peninsula side where paired panel number 43-44 has been lifted to the design elevation. The total length of the opposed cantilever sections of the main steel stiffening girder is now exactly 900 meters or 81.5% of the total length of the 1104-meter long channel span of the bridge over the Eastern Bosphorus Strait.

It will take just 10 lifts of paired and single sections on both sides of the strait including the closing panel number 52 to complete the world record central span deck. The preassembly of the final section has been already completed on the Nazimov peninsula building ways. An original design concept has been developed to install the closing section: the final panel number 52 will be lifted by two installation units to tie up together the two cantilever sections of the main stiffening girder of the bridge over the Eastern Bosphorus Strait.

Photo by Igor Lischuk / SK MOST