SEISMIC DISPLACEMENT OF A ROLLING-BASED ISOLATION SYSTEM

With an isolation system based on pure rolling as the study object, the computer program was compiled to calculate the characteristics of seismic displacement subjected to harmonic loadings and earthquakes. Results show, as for the seismic displacement of structure, the influence of the structural mass, stiffness and earthquake's frequency are relatively little, while the influence of earthquake's peak acceleration, duration and wave shape are great. When subjected to earthquakes, the structural maximum relative displacement may be larger than the ground's maximum absolute displacement, therefore, the problem of pure rolling is not a simple seismic problem with long-period. Although several accelerograms are generated from the same response spectrum, the obtained seismic displacements of one structure may be absolutely different, therefore, the motion of isolation system based on pure rolling is a random process which is closely related to the input process of earthquakes.