Abstract: A seismic isolation apparatus includes a laminated body having alternately laminated rubber plates and steel plates; a hollow portion provided inside the laminated body in a hermetically closed manner and extending in a laminated direction; a lead plug filled densely in the hollow portion and adapted to damp the vibration in a shearing direction of the laminated body by absorbing vibrational energy in the shearing direction; and a lid member having a semispherical concave surface which comes into contact with one end portion in the laminated direction A of the lead plug in order to guide and assist the plastic flow of the lead plug at one end portion in the laminated direction of the hollow portion in the deformation in the shearing direction of the lead plug.

Abstract: A seismic isolation apparatus 1 includes a laminated body 7 having alternately laminated a plurality of elastic layers 2 and rigid layers 3, and a lead plug 17 being disposed therein without clearances in a hollow portion 14 extending in a laminated direction V of the laminated body 7 with respect to inner peripheral surfaces 15 of the elastic layers 2, inner peripheral surfaces 16 of the rigid layers 3, a lower surface 12 of an upper plate 10, and an upper surface 13 of a lower plate 11.

Abstract: A seismic isolation bearing for a bridge includes rubber plates, steel plates and a laminated body; a hollow portion provided inside the laminated body in a hermetically closed manner; and a lead plug filled densely in the hollow portion. The lead plug has a pair of rectangular faces extending in a bridge axis orthogonal direction and opposed to each other in a bridge axis direction and a pair of rectangular faces extending in the bridge axis direction and opposed to each other in the bridge axis orthogonal direction.

Abstract: A seismic isolation apparatus 1 includes a laminated body 7 having alternately laminated a plurality of elastic layers 2 and rigid layers 3, and a lead plug 17 being disposed therein without clearances in a hollow portion 14 extending in a laminated direction V of the laminated body 7 with respect to inner peripheral surfaces 15 of the elastic layers 2, inner peripheral surfaces 16 of the rigid layers 3, a lower surface 12 of an upper plate 10, and an upper surface 13 of a lower plate 11.

Abstract: A seismic isolation apparatus includes a laminated body having alternately laminated rubber plates and steel plates; a hollow portion provided inside the laminated body in a hermetically closed manner and extending in a laminated direction; a lead plug filled densely in the hollow portion and adapted to damp the vibration in a shearing direction of the laminated body by absorbing vibrational energy in the shearing direction; and a lid member having a semispherical concave surface which comes into contact with one end portion in the laminated direction A of the lead plug in order to guide and assist the plastic flow of the lead plug at one end portion in the laminated direction of the hollow portion in the deformation in the shearing direction of the lead plug.