Finite Element Analysis on Damping Properties of Lead-rubber Bearings

摘要

The equivalent linear damping ratio and the energy dissipation of lead-rubber bearings are studied by finite element simulations on lead-rubber bearings. The FEA program ANSYS is adopted to establish a quarter model of lead-rubber bearing to simulate the hysteretic loop of LRB under the sinusoidal bads. The advantage a-bout the simplified finite element model is not only reducing the operating time, but also improving the efficiency and showing good agreement with the actual situation. The results are demonstrated that the horizontal shear strain and diameter of the lead had a primary influence on damping properties. The equivalent damping ratio decreased, the energy dissipation increased as a result of the horizontal shear stain increasing. Because the damping properties were very sensitive to small horizontal shear strain and the sensitive decreased with the horizontal displacement increasing. This decreasing tendency of the equivalent damping ratio according to the horizontal shear strain became less obvious when the horizontal shear strain was high, which indicated that the ability of energy dissipation was better under the small shear stain. And the both properties increased with the diameter of lead increasing. In addition , the damping properties had a slight influence on compression, shape factor and shear modulus of rubber. Finally, in a certain seismic intensity, it can be seen that the damping properties are mainly relevant to the diameter of lead.