Specialist of Krylov State Research Center (Saint-Petersburg) have carried out the mathematical and experimental modeling of the operation on transportation of Crimea Bridge’s navigation arches (highway and railway ones), says Crimean Bridge information center.
The assembled arches will be delivered from the Kerch side to the support structures to be installed as designed. Krylov Center specialists have determined the maximum of wind speed, sea current and waves as well as the number and layout of tugboats to perform the operation.
The delivery of the arch spans to the installation site is one of the most challenging operations in the project and in general practice of domestic bridge engineering. The arch spans are the largest structures of the Crimea Bridge: the railway span is almost 6,000 t, the highway span is over 4,000 t. The length of both spans is more than 200 m. The depth of the Kerch Strait is almost comparable to the draft of pontoons, which is also a challenge as well as unstable winds in the Kerch-Yenikalsky canal.
To perform the works ordered by Crimea Bridge designers, Krylov Center made the models of the arch spans, pontoons and tugboats (1:60).
According to Sergei Solovyov, deputy head of Hydro and Aero-Dynamics Division (Krylov State Research Center) the tests took into consideration all possible directions and speeds of wind. According to Krylov Center findings, safe transportation of the structures is possible with wind speed of less than 10 m/s. The layout and number of tugs can be different.
Mathematical modeling was performed at the simulator complex allowing for taking into account lots of parameters in real-time mode.
To ensure smooth transportation of the structures, dredging is underway at the Kerch coast.
The system designed for transportation of the arch spans will consist of 4 pontoons joined as catamarans. They are under construction at Sevmorzavod in Sevastopol. According to Leonid Ryzhenkin, Deputy Director General of Sevmorzavod, 7,000 t of metal structures have been assembled already (70% of the total volume). “The work is being performed round the clock. It involves more than 500 people”, said Leonid Ryzhenkin.
Transportation of the structures to the site of installation is scheduled for late August – early September 2017. It will take three to five days to transport each span structure.