Compact 3-D floor isolation system provides seismic isolation for horizontal and vertical motion. Advantages Provides high performance seismic isolation for horizontal and vertical motion. In a major earthquake, shaking of the floor can be reduced dramatically by seismic isolation. A wide range of protection can be achieved from small vibrations to very large earthquakes. The height of the system is low, which impacts little on floor height. As the devices are small, they are relatively easy to install in existing buildings. Air springs and ball bearings provide smooth motion. Structure 3-D floor isolation system is made by adding air springs to a 2-D floor isolation system, which reduces vertical vibration. Function Air springs absorb the vertical motion of an earthquake gently with compressed air. In addition, inclination of the floor caused by load redistribution due to the rearrangement of the layout will always be levelled by the self-levelling mechanism which keeps the height constant. For seismic isolation of horizontal motion, compact-sized ball bearings and viscous fluid damper are used. Function and components Seismic isolation system (horizontal) Seismic isolation system (vertical) Functions Air spring Ball bearing Coil spring Viscous fluid damper To support load on the floor To provide smooth motion To reduce acceleration To restrict large displacement To prevent small force vibration To return to the original position after an earthquake Test Performance Test In order to confirm the effect of seismic isolation, an experiment on a large 3-D shaking table was carried out using an actual seismic record. Acceleration on the floor with seismic isolation was reduced to between one eighth and one twentieth in the horizontal direction, and reduced to between one third and one quarter in the vertical direction, demonstrating excellent performance.