Technologies and Solutions - Architectural Technologies

Base Isolation Construction Method: TOSI

In the conventional earthquake-resistant buildings, the tremor of the earthquake is directly transmitted from the ground and the building shakes greatly. In a base-isolated building, the base isolation device absorbs the tremor of the earthquake, which makes it possible to slightly shake the building.

Toyo Construction Seismic Isolation Construction Method (TOSI) received technical reviews on design method, construction method, durability and maintenance at the Japan Seismic Isolation Structure Research Committee (JSSI) of the Japan Construction Center, and high reliability was confirmed.


  • “High damping laminated rubber and laminated rubber with lead are alternately overlapped with “steel plate (hard)” and “rubber (soft)”. The heavy building is supported by “hardness of steel sheet”, while horizontal tremor of earthquake is isolated from the building by the “softness of rubber”.
  • The slow vibration of the laminated rubber will take time to return to the original position, and the damper is used for adjustment.
  • We examine the effect of base isolation by observation.

Construction examples

  • ●(1998)Sankutas-Yoyogi(Tokyo Metropolitan)
  • ●(2013)New governmental office of Kinokawa city(Wakayama pref.)
  • ●(1999)Gueru-Huchinobe(Kanagawa pref.)
  • ●(2013)Miyagi Distribution Center, Ricoh Logistics System Co., Ltd. (Miyagi pref.)
  • ●(2008)Espoir Ayase(Tokyo Metropolitan)
  • ●(2016)North Fire Station of Okayama city (Okayama pref.)
  • ●(2012)Advanced Trauma, Emergency and Critical Care Center, Oita University(Oita pref.)
  • ●(2017)Iwate Hospital, National Hospital Organization(Iwate pref.)
  • ●(2012)Shinonome Residential Tower(Tokyo metropolitan)
  • ●(2019)New governmental building(Wakayama pref.)