Seismic Reductions Based On Combined Friction Isolation Structure Under Near-fault Earthquakes

In recent years, more and more of the base isolation technology sparked widespreadattention in academia. Base isolation is installed in the structure vibration isolation device,the deformation of the structure under earthquake are mainly concentrated in isolationlayer, thereby prolong the cycle, reduce the structural seismic responses of structure.Base-isolated structure under far-field earthquake can achieve good damping effect, but inthe long pulse cycle speed and displacement effect of the action under near fault ofearthquake, and it could cause serious damage to structure of base isolation system.In order to reduce the negative impact under the near fault earthquake, in my paper,the seismic isolation structure based on the basic structure of the isolation layer frictiondamping is added to form a combined friction isolation system, reduce the structure of theinput seismic energy, and improve the safety of the main structure.This paper established a theoretical model of combined friction isolation structure,selecting far-field and near-fault earthquake ground motion records as input, for analyzingthe dynamic response of base isolation structures and combined friction isolation structureunder seismic earthquakes. The main work includes the following aspects:(1) In this paper, by using SAP2000software, choosing Wen connection unit,combined friction isolation structure analysis model is established, and numericalcalculation of base isolation structure and combined friction isolation structure underseismic action of the interlayer displacement, acceleration at the top of the upper structureand isolation layer shear force, analyzed seismic reduction of combined friction isolationstructure.(2) Combined friction structure under the action of earthquake response is associatedwith the sliding force of friction damper, the earthquake response changed by the changingof the sliding force of combined friction structure, the analysis result provided a basis foroptimal selection of sliding force.(3) Comparing the seismic response of the base isolation structure and combinedfriction isolation structure, including the max acceleration response, drift of the floor and base shear response, analyzing seismic reduction of combined friction isolation structure.