Evaluation of the performance of a suspension isolation system subjected to strong ground motion

✍ Scribed by Bakhshi, A.; Araki, H.; Shimazu, T.

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 837 KB
• Volume: 27
• Category: Article
• ISSN: 0098-8847
• DOI: 10.1002/(sici)1096-9845(199801)27:1<29::aid-eqe717>3.0.co;2-o

✦ Synopsis

This study is concerned with a new isolation device called a Suspended Pendulum Isolation (SPI) system here. Particular attention is given to evaluate the dynamic behaviour of the system under substantial ground motions including the El Centro 1940, Hachinohe 1968 and Kobe 1995 earthquakes. Shaking-table tests have been carried out for a -scaled model comprising a test structure supported on the SPI system with lead damper. Several yield strengths for the lead damper are examined to investigate its properly designed dimensions. Experimental results show that the SPI system with lead damper has a substantial capability to decrease either peak acceleration or peak base (bearing) displacement responses for broad-band frequency excitations. It also confirms that maximum-storey drift index of isolated structure has been dropped to about one-sixth of its corresponding value at fixed-base condition under strong level of predominant excitation along with considerable decrease of peak acceleration. A non-linear analytical model for an MDOF shear building has been also developed by utilizing the fourth-order Runge-Kutta algorithm. Comparison of analytical and experimental time-history responses for all of the excitations indicates that there is a good agreement in both peak values and shape pattern of the results. Moreover, SPI with an appropriate yield strength of lead damper creates only a very small permanent displacement after strong excitation. 1998