Abstract:To solve the difficulty in 3D seismic isolation of high-rise structure, shaking table tests and numerical simulations under multi-dimensional excitation of an aseismic mega-sub structure and a mega-sub structure based on three-dimensional seismic isolation of sub structure were performed. Firstly, prototype structure, model structure and shaking table test scheme were introduced. Then, shaking table tests of two model structures were carried out, the structural seismic responses were measured and analyzed, and furthermore, test results were compared with numerical simulation results. Finally, the multi-dimensional seismic response analyses on the prototype structure were conducted. Experimental results and simulation results show that the natural vibration periods of structure in horizontal and vertical directions are prolonged, although the three-dimensional seismic-isolation bearings arranged beneath the base of sub structure are different from those seismic isolations from the perspectives of seismic-isolation forms and damping mechanism. Simulation results agree well with test results. Seismic-isolation sub structure has remarkable damping effect on the seismic response of main structure under different ground motions. Three-dimensional seismic-isolation bearing also has isolation effect on the multi-dimensional seismic responses of sub structure. If displacement responses of seismic-isolation layers do not exceed the width of seismic-isolation joint, sub structures shall not collide with the main structure.