Proceedings of the 7th World Congress on Mechanical, Chemical, and Material Engineering (MCM'21)
Prague, Czech Republic Virtual Conference – August, 2021
Paper No. ICMIE 116
DOI: 10.11159/icmie21.116

Response of Base Isolation System for Small Exhibits in the Museum
Katsumi Kurita1, Shigeru Aoki2

Department of Mechanical Engineering, Tokyo Metropolitan College of Industrial Technology
1-10-40 Higashi-Oi, Shinagawa Tokyo, Japankatsumi@metro-cit.ac.jp
2
Department of Mechanical Engineering, Tokyo Metropolitan College of Industrial Technology
1-10-40 Higashi-Oi, Shinagawa Tokyo, Japanaoki@g.metro-cit.ac.jp1

Extended Abstract

Small exhibits displayed in the museum had been overturned and damaged by big seismic ground motion [1], [2]. Inorder to reduce the risk of seismic damage, some small base isolation systems for small exhibits, that are possible to installinside buildings, have been developed [3]-[5]. However, their mechanisms have been complicated and cost too much, thesystem is not popular in the small-scale museums. Therefore, we have proposed a simple seismic isolation system for exhibits
in the museums [6]. In order to investigate effectiveness of the system, dynamic characteristics of the system are investigatedby vibration experiment.
The simple isolation system consists of two aluminium metal plates coated with solid lubricant. A large lower plate is
500×500 mm size, a small upper one is 125×125 mm size. A friction coefficient between two plates is 0.12. Sincemechanisms of the system are quite simple, it is easy to maintain it.
To confirm effectiveness of the system, the excitation experiment was performed using a seismic ground motion of Mid
Niigata Prefecture Earthquake in 2004 recorded at K-NET NII019 (K-NET Ojiya) as the input wave. The peak acceleration

amplitude on the input wave indicated 1313 Gal, the peak response amplitude on the system was 221 Gal. Since
it has reduced to about 1/6 against the peak acceleration amplitude on the input wave, the system is effective toreduce the response on seismic ground motion. Next, the effectiveness of overturning prevention for small exhibits wasinvestigated by excitation experiment. In the experiment, a vase that overturing acceleration amplitude is 400 Gal, wasinstalled on the upper plate of system. The response waveform on the upper plate was enough reduced. Although a part of
the response waveform on the top of the vase identifies such as pulse, it indicates that the vase generated rocking motion.
And the vase did not overturn. In fact, the peak response acceleration amplitude on the upper plate is 221 Gal, is lower theoverturning acceleration of the vase.
The system is effective to prevent overturning of small exhibits in the museums by seismic ground motion.

References[1] D. Strahan, “Seismic mitigation at the Asian art museum in San Francisco”, Advances in the Protection of Museum
Collections from Earthquake Damage, 2006, pp. 107-113.
[2] C. Spyrakos, I. Koutromanos and C. Maniatakis, “Case study: A review of seismic mitigation efforts for museums inGreece”, Advances in the Protection of Museum Collections from Earthquake Damage, 2006, pp. 115-134.
[3] T. Ohmachi, M. Takase and T. Toshinawa, “Present earthquake countermeasures for art objects in museum anddevelopment of a base-isolated display stand”, Journal of Structural Mechanics and Earthquake Engineering(I),No.507, pp. 191-199, 1995 (in Japanese with English abstract).
[4] S. Ueda, M. Akimoto, T. Enomoto and T. Fujita, “Study of roller type seismic isolation device for works of art”, Trans.
Jpn. Soc. Mech. Eng. C, vol. 71, 703, pp. 807-812, 2005 (in Japanese with English abstract).
[5] J. M. Schoettler and A. Stavridis, "Finalizing the design of seismic isolations for the antiquities collection of the J. Paul
Getty Museum, Advances in the Protection of Museum Collections from Earthquake Damage, 2006, pp. 71-83.

ICMIE 116-1