Reconstruction of a bridge over the Don River continues at the 280th kilometer of the Morozovskaya – Volgograd Section of the Privolzhskaya Railway Line. Installation of the first abutment span structure has been completed. Preparations are underway to start installation of the second abutment span structure.
The abutment span structure that is 33.6 meters long is mounted on pillars number 9 and number 10 on the left-bank side of the Don River. The installation was carried out on temporary supports using the RDK-400 Crawler Crane. Preparations are conducted to install the second abutment span structure on pillars number 1 and number 2 on the right bank of the river. Installation of the second abutment span structure is scheduled for June this year. The abutment pillars number 1, 2, 9, 10 have been erected last year, and the builders are going to complete construction of four channel pillars number 3, 4, 5, 6 this year.
Construction of channel pillars number 7, 8 began. Enclosure sheet piles are being driven on pillar No. 7 site. Before driving the sheet piles, fragments of a reinforced concrete railway bridge which was destroyed during the World War II had been recovered from the river bed in the pillar site area.
Construction of pillar number 8 is the most challenging phase in building the bridge. The eighth pillar is located between the fairways, and the water in this area is as deep as 20 meters. Because of the deep water in this location, the pillar will be erected using a submerged bottom, without driving sheet piles. The pillar will have a high-profile grillage, which will not bear against the river bottom. Twenty two 1500-millimeter diameter drilled piles will be first put in place in the pillar footing. A submerged steel bottom will be then sunk to a depth of 13 meters, and a steel sheet-pile box structure will be installed on the steel bottom. The submerged steel bottom will be used as a support for placing a grouting layer and for grillage concreting. After the grouting layer has been completed, water will be pumped out of the steel box structure, and the pillar will be erected using conventional techniques.
Two channel span structures, each 77 meters long, will be assembled on building ways this year as well. The two spans of a total length of 144 meters will be tied up by means of a joint member. This paired span will be installed on pillars number 4, 5, 6 using a floating support system during the 2014 navigation period. The second paired span structure of a total length of 144 meters will also be installed next year on pillars number 2, 3, 4. Installation of paired span structures using a floating system is a very complex operation. This operation will be carried out for the first time in the Russian bridge-building history.
Hydraulicking has been carried out simultaneously with pillar erection and span structure installation. Roadbed for railway approaches to the bridge is being hydraulically filled on the right bank. About 1.0 million cubic meters have already been filled (a total of 1,400 thousand cubic meters have to be filled as per design). The roadbed is filled on the left bank using a syphon pipe: the soil that is hydraulically filled is conveyed from the right bank to the left bank through a special pipe laid on the river bottom. About 400 million cubic meters have already been hydraulically filled on the left bank (a total of 1,200 thousand cubic meters have to be filled as per design). Hydraulicking to fill an assembly ground has been completed on the left bank, and rolling piers have been erected there for assembling the channel span structures.
Aleksandr Ryblov, Sergej Sysoev / SK MOST