Study On Construction Technology Of Large-span Catenary Steel Pipe Truss Structure

The large-span space steel structure is widely used in large complex buildings such as stadiums,exhibition centers,shopping malls and factory workshops because of its graceful shape,flexible spatial arrangement,and good seismic performance.However,the construction process of large-span space steel structure faces a number of problems due to the complex and time-varying structural system,difficulty in controlling quality and safety,and other challenges.Therefore,a scientific,reasonable,efficient,and safe construction scheme must be formulated according to the structural characteristics,site conditions,construction period requirements,and crane tools to solve the key technical problems existing in the construction process.Taking the northside group project of Shanxi Xiaohe International Convention and Exhibition Center as the object,this thesis carries out the research and design of the installation process of largespan catenary pipe truss,the design of auxiliary turning device,the simulation and checking calculation of the whole construction process and the reverse shape-finding analysis of the roof structure.The main research contents of this thesis are as follows :(1)The engineering situation and project characteristics of the large-span catenary pipe truss project are introduced in detail.Based on the structural form of the pipe truss,the construction site environment,the lifting capacity of the equipment,and the common construction methods for large-span space structures,the scheme of ’ double crane hoisting +auxiliary turning device ’ is established.The splicing and lifting process of the pipe truss structure is designed.(2)According to the concept of green,assembled and reusable,the product design of the auxiliary device is carried out.The finite element analysis software Abaqus is used to ensure the mechanical properties of the device.The results show that the device is detachable and reusable,which can safely and effectively assist in the installation of the pipe truss structure.(3)The finite element analysis software Midas Gen is utilized to establish the model of this project,and the processes of construction simulation are carried out for the steel structure project,and the mechanical state and geometric dislocation of the structure in different construction process are analyzed.The results show that the excessive horizontal displacement of the structural column and the inconsistent roof elevation are the two main difficulties in the construction process.(4)Based on the above analysis results,suggestions are proposed for the construction scheme.The fixed hinge support on one side of the pipe truss is released into the sliding hinge support to reduce the horizontal displacement of the column top.The forward iteration method is used to perform reverse shape-finding analysis on the installation coordinates of key nodes of the main truss to meet the installation requirements of the roof system.Deformation monitoring is carried out in the construction process.Deformation monitoring is carried out during the construction process,and the results show that the numerical analysis results are in good agreement with the monitoring data.The construction plan proposed in this thesis can effectively solve the main technical difficulties in the construction process.The research results of this thesis have been successfully applied to the construction scheme of the large-span catenary steel pipe truss in the northside group project of Xiaohe International Convention and Exhibition Center in Shanxi Province.A total of 6500 tonne roof steel structure is installed.On the premise of ensuring the safety and reliability of construction and good quality,the cost is reduced by 980.8 thousand yuan.The technology has been registered as a major achievement in construction science and technology by Department of Housing and Urban-Rural Development of Shanxi Province.(Key technology research on safety control of large-span steel structure catenary roof construction process,First Class,Certificate number: JSKJCG1008,Department of Housing and Urban-Rural Development of Shanxi Province,December 24th,2021).