On 6th October, Shougang completed the installation of the 2022 Beijing Winter Olympics ski jumping platform referee chamber. Using its in-house developed SQ345FRW, Q345GJDZ25 steel plates, matching welding materials and bolts, Shougang delivered as scheduled with both quality and quantity, ensuring the high standard, top quality and efficient construction of the ski jumping platform project.

The Shougang ski jumping platform is the only snow venue in the 2022 Beijing Winter Olympics. It is the first world’s first permanent ski jumping course. The secondary structure can be used for other snow-related events such as aerial games. For crowd-intensive place such as the jumping platform referee chamber, it is necessary to make sure that the steel material is corrosion resistance and has high fire-resistant property, so as to ensure that the structure can support and last long enough to allow crowd evacuation. Hence there are very high requirements regarding the mechanical property, welding performance, fire and weather resistance of the steel material. In support of the building of the Olympic “high-quality project”, Shougang Technology Research Institute, Shougang Construction Investment Co., Ltd., Shougang Architectural Design Co., Ltd., Jingtang Company, Guigang, Changgang and other entities, through common consensus, decided on the application of the fire and weather resistant steel in the jumping platform referee chamber.

In the production process of 80mm thick Q345GJDZ25, the R & D team of the technology research institute actively faced and tackled the issues. After many rounds of demonstrations and field tests, they took measures such as alloy baking, billet insulation, high temperature rolling and slow cooling to improve the passing rate of steel plate flaw detection. Through reducing the deformation temperature in the rolling process, they achieved dislocation strengthening to guarantee the strength of the steel plate; Precise adjustment and control of the temperature parameters during production optimized the design of the alloy composition system. The adjustment of the water inlet temperature and the final cooling temperature of the steel plate ensured the strength and smoothness of the steel plate.

The fire resistance and corrosion resistance properties of steel joint determine the safety of the entire structure. There was no successful case both domestic and abroad in the development of 10,00MPa fire and weather resistant steel bolt to match the SQ345FRW fire and weather resistant steel plate which was to be used for the jumping platform referee chamber. The research and development team pursued independently to design the composition system for the bolts. The final bolt product was able to match and complement the fire resistance performance, weather resistance performance and self-corrosion of the supporting plate. It also demonstrated anti-delay fracture capability lasting for 100 hours without fracture, realizing the engineering application of bolt products. Regarding the development and design of matching welding materials, the welding team of technology research institute successfully developed the matching welding materials after re-designing and testing of 24 components. At the same time, being a key project of the Winter Olympic Games, Shougang had adhered to the “Green Olympic Games” in all aspects during construction, and followed the concept of green environmental protection, taking protective coating measures to ensure the fire resistance and corrosion resistance of steel plate while carrying out thinning treatment.

Finally, through the joint expert group demonstration and inspection, comprising of China Academy of Building Research, Tsinghua University, University of Science and Technology Beijing and other authoritative organizations, it was concluded that the SQ345FRW fire and weather resistant steel, matching bolts, welding materials and protective coating measures fully meet the quality requirements of the ski jumping platform referee chamber project. The complete set of fire and weather resistant steel technology of Shougang has been successfully applied to the ski jumping platform referee chamber project. It has realized a leap from the steel works project to the international stadiums and gymnasiums.