Abstract: Hangzhou Olympic Sports Center Comprehensive Training Center is one of the venues for the 19th Asian Games in Hangzhou 2022. The underground steel structure has the characteristics of component weight, special section shape and complex construction conditions. The outer cylinder of the main building on the ground adopts oblique steel tube grid column which is cross-braided with the ground at 56.3°.Large diameter, large number of grid column and heavy components make it difficult to locate on site. Especially, the structure and stress of oblique grid joint are complex, and there are many hidden welds and intersecting welds with small angle, which bring great difficulties to the processing welding and installation on site.
By closely cooperating with civil construction, optimizing the arrangement of civil steel reinforcement and reducing the interference between steel structure and civil steel reinforcement, and reasonably organizing the construction sequence, the influence of multi-specialty cross construction was solved. In the complex construction environment, the circular construction road that meet the construction requirements was opened. Scientific hoisting methods and stable temporary measures were used to ensure the safety of the structure in the construction process. Adopting digital measurement technology of "computer-aided electronic total station" to control the installation precision of components; in the process of deepening the design, through a large number of analysis tests and studies, the welding requirements of skew grid joints were innovatively optimized, and the feasibility of the optimized scheme was verified by finite element analysis. The finite element analysis for steel structure construction process was carried out, according to the results of the simulation analysis, the key parts and links to be monitored in the construction process of steel structure were determined; according to the stress and displacement of the cantilever parts during construction,the principle of priority to dismantle the most disadvantageous support was determined, and the cantilever support was removed by stages. The above method had been successfully applied in this project, which provided certain reference for similar steel structure engineering.