PURPOSE: To improve damping function by providing a thin plate-shaped annular reinforcing member and an annular rubber layer, a laminated base isolation member, a viscous body in the above base isolation member, and a resistance body which is extendingly provided in the inner peripheral part of the annular reinforcing member and protrudes into the viscous body.
CONSTITUTION: A fixing member 1 is formed of an annular plate, and provided with four attaching holes at equal spaces in its peripheral direction for making a base isolation member 2 fixable on both the sides of a ground surface and of a building. In this case, an annular reinforcing member 20 and a thin plate-shaped annular rubber layer 21 are mutually laminated and stuck to compose the base isolation member 2, whose outer periphery is encircled with rubber material being the same in kind as the annular rubber layer 21. Next, a viscous elastic body 3 is filled up in a central cavity part in the base isolation member 2. Next, when shearing force caused by an earthquake acts on the base isolation member 2, moving resistance occurs between the viscous elastic body 3 and a part (a) protruding into the viscous elastic body 3 of the annular reinforcing plate 20 with the deformation of the base isolation member 2. A concentrated load partially acting on a resisting body is thereby checked to display sufficient damping function for a long term.
KURODA SUSUMU
KIYOHARA YOSHIHARU
