The complex and variable external environment temperature in the installation process of GIS has a non-negligible impact on the installation positioning deviation and internal forces of structure part

causing a large difference between the complete installation state and the design state. Based on an actual substation project and in combination with the local temperature environment of the project

four different temperature variation conditions are set up. The birth and death element method based on the time-varying mechanics is adopted for the finite element simulation analysis of the installation process of GIS and the influence of temperature effect on structural displacements and stress during the installation process is studied. The simulation results show that the temperature variation in the installation process has a cumulative effect on the displacement deviation of GIS bays

and the displacement deviation will affect the installation positioning requirements. The base is connected by the bolt with less rigidity which

in case of significant temperature effect

has no way to coordinate the deformation of the upper structure and the lower frame. With the temperature variation during the installation period

the stress of the enclosure varies correspondingly but with small stress value

relative large internal force of bolt and small safety margin. The study result will lay the foundation for control of installation environment structure optimization for the GIS structure.