Article: Tuğrul Özkan, General Manager of Bülbüloğlu Çelik (BCES)
Manufacturing and assembly processes of the Japoma Olympic Stadium and Sports Complex project carried out in Cameroon was completed in a short period of time by Bülbüloğlu Çelik company, which carries out integrated method systems with steel construction manufacturing, quality, environment, occupational health and safety, welding qualification, CE Marking certificates. At every stage of the manufacturing and assembly processes of the project, control and approval procedures were carried out by the independent organization assigned by Yenigün İnşaat.
The concept project, which was created with the approval of architectural, static and consultant companies, was solved with S355JR quality pipe materials, while the static calculations of the project were analysed with the SCIA program. Connection calculations were also confirmed and developed by analysing in detail with the finite element method with the IDEASTATICA® program. A total of 48 steel trusses were designed and the roof covering of the project is membrane and transparent polycarbonate.
The project includes a stadium with a capacity of 55 thousand seats, a sports hall with a capacity of 2,000 seats, an Olympic swimming pool with a capacity of 2,000 seats, 2 training fields and tennis courts. 80% of the construction materials, teams and equipment used in the Jacome Olympic Stadium and Sports Complex project were brought to Cameroon from Turkey.
IT BECAME THE FASTEST COMPLETED PROJECT
The employer demanded that the project be completed for the Africa Cup of Nations, one of the most important organizations of world football. According to the contract conditions signed in line with this request, the entire scope of steel construction including the manufacturing and assembly periods in 6 months, which was completed by Bülbüloğlu Çelik Company, is much shorter than similar projects,. In addition, 6 projects within the scope of the Africa Cup of Nations started close to each other, and this project was appreciated by the Cameroon management and the CAF Board as the project of which assembly was the fastest completed.
In the welding process of the project, pipe joint welding was carried out in accordance with EN 1090-2 Exc 4 level, under the management of welding engineers of Bülbüloğlu Çelik, with its synergetic welding machines.
SPECIAL CORROSION PROTECTION
The fact that the climate zone where the project is implemented is located in the Equatorial region brings with it a high risk of corrosion due to excessive humidity and proximity to the ocean. In this context, considering the requirements of the project, an epoxy/polyurethane paint system for C5 corrosion class was applied in accordance with EN 12944-5 to protect the project from the high risk of corrosion.
During the erection process, the space frame structure was assembled in full dimensions in the ground formworks in the field and the bolts to fasten the structures were tighten by the appropriate torque values after the acceptance by the independent inspection organization, and the erection was completed with the high capacity cranes from both inside and outside the field.
The cross bracings of the entire stadium are balanced and fixed with Macalloys tension connectors. The length of the cantilever of steel trusses is 40 meters, and there is a cat walking path at the end. This walking path passes through the truss and surrounds the stadium. The mentioned path also loads the sound and lighting system. The strong structure of the truss successfully passed the tightness test against gustily monsoon rains.