Seismic Isolation Design and Effectiveness Analysis of Prefabricated Cabins in Modular Substations
Substations are considered as lifeline infrastructure,and modular substations feature a steel frame at the base of the prefabricated cabin for primary equipment,with equipment arranged in a single row inside the cabin.The seismic performance of both the steel-framed prefabricated cabin structure and the equipment within it needs thorough investigation and improvement.In this study,a nonlinear time-history analysis of the non-isolated structure under seismic loading was conducted using the finite element software ABAQUS.Following this,a seismic isolation design was implemented,and the seismic responses of both isolated and non-isolated structures were compared.Additionally,a parametric analysis was performed on the isolated structure,considering factors such as steel frame stiffness and the location of the seismic isolation bearings.The results indicate that the seismic isolation design effectively extends the fundamental period of the structure and provides improved control of both acceleration and displacement during seismic events,compared to the non-isolated structure.For the structure analyzed in this paper,a steel frame with an H140 cross-section dissipates seismic energy primarily through deformation,limiting the effectiveness of the isolation bearings.Furthermore,seismic isolation bearings positioned at the bottom of the column demonstrate better control over equipment acceleration and cabin displacement compared to those placed at the top.However,tensile forces may develop in the isolation bearings at the bottom.Therefore,it is recommended that the steel frame at the base of the isolation bearing have adequate stiffness(with a suggested stiffness of no less than 3 615 kN/m when the upper compartment weighs 25 tons).Additionally,the position of the isolation bearings should be selected carefully,considering both the forces acting on the bearings and their impact on the overall seismic isolation performance of the structure.
Modular substationPrefabricated cabinVibration isolation designEarthquake responseTime history analysis
万方数据
维普
