SEISMIC ISOLATION ANALYSIS OF SMA SPRING-FRICTION BEARINGS IN DOUBLE LAYER SPHERICAL LATTICE SHELL STRUCTURES

In this paper, the friction bearing conbined with large size SMA coil springs is put forward to develop a new type of isolator entitled as SMA spring-friction bearing(SFB). Based on the configuration and working principle, theoretical model of mechanical performance of the SFB is derived. In order to investigate feasibility and vibration reduction effect of the SFB in double layer spherical lattice shell structures, column top isolation structrue including such SMA-based bearings between the lattice shell roof and substructure is considered. The finite element analysis software SAP2000 is utilized to establish the numerical model of isolated lattice shell structure with substructure. Numerical simulation of dynamic response of the seismically isolated structure is carried out. The calculation results indicate that the proposed SFB can reduce the seismic response of the lattice shell structures effectively. The results also show that the SFB has excellent bearing displacement control performance and re-centring capability.