– horizontal – modified Sierra Madre California seismogram,
– vertical-zzðtÞ ¼ 0:0005 sin ð2π0:7tÞ þ 0:0005 sinð2π1:91tÞþþ0:001
sinð2π1:92t þ 90Þ where the value 1.92 Hz corresponds to the
frequency exciting the main parametric resonance in the
pendulum.
Fig. 15 shows comparison of the vibration of a numerical
model with a TMD in the case of excitations: