Dynamic characteristics and seismic response of base-isolated structures with negative stiffness devices
Setting a negative stiffness device in the isolation layer can adjust the dynamic charac-teristics and seismic performance of base-isolated structures.The force-displacement relationship was linearly approximated by Taylor series expansion to address the nonlinearity problem caused by the preloaded spring in the isolation layer and the frequency response characteristics of base-isolated structures with a pure negative stiffness(PNS)element and a damping negative stiffness device(NSD)were compared and studied.Furthermore,the wavelet analysis was used to per-form the time-frequency analysis on actual near-fault earthquakes,and the analytical mode decomposition method was used to decompose the ground motion into high-and low-frequency components.The effects of PNS and NSD on the seismic response of base-isolated structures under high-and low-frequency seismic waves were then compared.Compared with the base-isolated structure with-out NSD,results show that setting PNS can reduce the displacement and acceleration responses under high-frequency excitation but increase the displacement and acceleration responses under low-frequency excitation.Setting NSD not only markedly reduces the peak values of displacement and acceleration frequency response functions of base-isolated structures but also minimizes the displacement response of base-isolated structures in a wide frequency range.
万方数据
维普
