For studying the seismic response of gas insulated metal enclosed transmission line (GIL)

the seismic simulation vibration stand test and finite element analysis of a 550 kV GIL pipeline unit are performed

and the partial GIL finite element model under the whole station domain is set up based on the tested and verified GIL pipeline unit model to study its seismic performance under multi point input. The research result shows that the safety factor of the three pillar insulators under the test and finite element analysis is minimum and is the weak part of GIL; The finite element analysis result of GIL pipeline unit is in good agreement with the vibration stand test result

and the maximum error of mode analysis

peak acceleration response and Von-Mise stress are 8.5%

8% and 12% respectively

indicating that the established finite element model and parameter setting are reasonable. The stress response of key parts of GIL under

YZ

2D multi-point input is greater than the consensus input

and the displacement peak response is increased by 31% over the consistent input. Therefore

the influence of multi-point input shall be considered in the GIL seismic design. The input of the seismic response at 3D (150 m/s) of GIL is small

and is increased by only 6.4% compared to

YZ

2D multi point input. Therefore

in the engineering design

only consideration of the 2D multi-point input can meet the requirements of the engineering calculation.