Segmented multidimensional seismic isolation control of spherical lattice shell structures

Spherical lattice shell is a typical long-span space structure and its seismic response is evidently influenced by horizontal and vertical components of ground motion.Bearing-type isolation devices can be utilized to form a segmented multidimensional isolation mechanism to improve the seismic performance of the spherical lattice shell structures.In such structures,disc spring bearings can be introduced to constitute a vertical isolation system and cooperate with two types of horizontal isolation device:(1)the friction pendulum system(FPS) bearings;(2)the SMA-rubber bearings.Based on conceptual design mentioned above,the configuration plans of the vertical and horizontal isolation bearing were developed,and the corresponding calculation models were established.According to dynamic equations for the lattice shell structures with multidimensional seismic isolation system,seismic analysis was executed for both double-layer and single-layer spherical lattice shell under El Centro wave.The numerical simulation results show that the vibration-reduction effectiveness of the internal force,acceleration and displacement of such seismically isolated structures is up to 50% or more.Therefore,the presented multidimensional isolation technology can be effectively used to protect the spherical lattice shell structures from damages of earthquake.