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Proceedings of the International Conference on
Advances and New Challenges in Earthquake
Engineering Research, Hong Kong Volume
TOWARD THE REALIZATION OF SEISMICALLY ISOLATED
LARGE-SPAN SPATIAL STRUCTURES:
MODEL TEST AND SIMULATION
T. Matsui 1 , E. Sugiyama 2 , F. Qiao 3 and T. Hibino 4
'Department of Environmental Engineering and Architecture,
Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
2 Ito Architects & Engineers Inc., Nagoya, Japan
3 0gawa Tec Corporation, Tokyo, Japan
Department of Architecture, School of Engineering, Nagoya University, Nagoya, Japan
ABSTRACT
Until recently few research efforts have been directed toward the application of seismic isolation
system in large-span spatial structures. This is due to the light weight and relatively long natural period
of this type of structure which makes it difficult to apply the commonly used isolation system
composed of laminated rubber isolators and dampers for multi-story buildings. In this paper, the use of
a seismic isolation system with sliding mechanism is proposed for large-span spatial structures. In
order to confirm its effectiveness in reducing the seismic response, shaking table tests are performed
using a small-scale arch model. The test results are utilized to validate the simulation method, which is
then applied to investigate the seismic response of a 200m span latticed dome supported by the baseisolation
system. It is confirmed that the proposed seismic isolation system is effective in reducing
substantially the horizontal and vertical accelerations as well as member stresses due to horizontal
ground motions.
INTRODUCTION
Large span spatial structures such as gymnasia or auditoria are requested to have higher level of safety
against earthquakes because they always accommodate many and unspecified spectators and are often
used as regional refuges once the disaster occurs. In order to protect the structure from severe damages
and to prevent the drop of hanging equipments or ceiling panels due to strong earthquake motions, it
seems to be effective to employ a seismic isolation system. Especially, in view of the brittle nature of
the failure of this type of structure and the difficulty of repair of damaged members over the large span
roof, it is desirable to retain all the members within the elastic range even under extremely rare strong
earthquake. This is only possible by employing the seismic isolation system. The seismic isolation is
also effective to release thermal stresses, and to prevent the failures caused by unequal movement of
the supporting structures which were frequently observed at Kobe Earthquake in 1995.