基于地震模拟振动台试验的铅芯橡胶隔震 支座静力性能修正

At present, the mechanical performance parameters of the rubber bearings are obtained by the pseudo-static test in the seismic isolation design of structures. But for the rubber bearings under actual earthquake, whether their dynamic performance are consistent with those of the pseudo-static test, the magnitude and degree of the difference are the key problems affecting the safety of the base isolation structures, so further research is needed. In this paper, the lead rubber isolation bearings which is widely used, was selected as the research objective, and the pseudo-static test and the shaking table test of lead rubber bearing were carried out and were compared firstly. The change laws of mechanical performances such as hysteresis curve, yield stiffness and yield force of lead rubber bearings under different earthquake records and shear strain were studied. At last, the modified formula of the static performance parameters considering actual earthquake dynamic effect was put forward. It can be seen that the hysteretic curve area and mechanical performance parameters of lead rubber bearings by pseudo static test are larger than those of shaking table test, which shows that the direct use of static test results in seismic isolation design will exaggerate the energy dissipation capacity of bearing and bring potential safety hazard to seismic isolation structure. The modified formula proposed in this paper takes into account the dynamic effect of actual earthquake on bearings. The research in this paper has important reference significance for seismic isolation design, and has important theoretical and practical significance for ensuring the safety and reliability of seismic isolation structure.