Influence of Earthquakes and Other Loads on the Layout of Gas-Insulated Substations

The mechanics of a Gas-Insulated Substation are a complicated problem, which can have a considerable influence on the layout of the equipment as well as on the supporting structure and foundation. Rather few papers dealing with this problem have been published. It is our experience that those concerned with selecting GIS-layouts not always are aware of all the precautions and considerations that have to be taken for mechanical reasons. Of the various forces that have to be taken into account the thermal and seismic loads usually have the greatest influence on the layout. Most of the loads that affect the substation will also have influence on the building and foundation. In this paper thermal loads, seismic loads and reaction forces from circuit-breakers are described in more detail, as well as methods to design with respect to these loads.