Rocking-type seismic isolation base for protecting structure against earthquake

Abstract

A rocking-type seismic isolation base for protecting structure against earthquake includes a body having a configuration similar to a generally recognized flying saucer. The base serves as a buffer when a structure is horizontally displaced relative to a supporting foundation of the structure, and largely reduces the vertical displacement of the structure. The rocking-type seismic isolation base also allows the displaced structure to automatically return to its original position. The base is provided at a bottom with a space for an anti-slipping lock to mount and freely move therein, so as to prevent the rocking-type base from horizontally slipping in a condition exceeded the designed seismic vibration. The rocking-type base may be cooperatively used with a saucer spring to further mitigate the vertical vibration.

1 . A rocking-type seismic isolation base for protecting a structure against earthquake, comprising a body having a configuration similar to a generally recognized flying saucer, and including a spherical upper surface allowing a member having correspondingly shaped matching surface to rotate and slide thereon, and a convex spherical lower surface allowing the base to rotate, roll, or rock on a foundation surface; wherein said spherical upper surface has a small radius relative to said spherical lower surface.  
   
   
       2 . The rocking-type seismic isolation base for protecting a structure against earthquake as claimed in  claim 1 , wherein said body is provided at said convex spherical lower surface with a bottom space having a curved inner surface for an anti-slipping lock device to mount and freely rotate and move in said bottom space.