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I. Goł˛ ebiowska and M. Dutkiewicz
Fig. 5 Analyzed frame with friction pendulum bearing and acquisition system
and friction coefficient is µ = 0.12. Following the measurements, as for the example
for the step 5.5, the amplitudes of acceleration increase from the 1.49 m/s
2 for the
frame and 2.90 m/s
2 for table.
Figure 7 presents power acceleration spectrum (PAS) for the step 5.5. The highest
value of power amplitude spectrum is for frequency 1.8 Hz.
Figure 8 presents summary of PAS of acceleration of top of the frame for steps
0.5–5.5.
Based on the analysis, with the increase of excitation, the frame accelerations
increase. In the step excitation range from 0.5 to 2.0, the acceleration increase of
table and frame is at the similar level. Significant differences in acceleration increase
of table and frame are observed from the step 2.5 and higher.
4 Conclusions
The paper presents the review of the most important friction sliding bearings used in
engineering objects exposed to seismic influences, in the context of their effectiveness
are presented.