Page 139 - Çevre Şehir İklim İngilizce - Sayı 4

Cenk Alhan - Mert Hacıemiroğlu

Another near-fault problem is high vertical ground accelerations, as mentioned
above, and this is also observed for the vertical component of RSN181 H-E06-
UP record. As can be seen in Figure 13, the peak ground acceleration of the
H-E06-UP vertical component increases to a very high level, such as 1.895 g. In
Figure 14, the acceleration spectrum with 5% damping belonging to the vertical
component of the RSN181 earthquake record is presented. As a result of the
modal analysis performed, the vertical vibration period of the building under
study was calculated as 0.176 s, and it is observed that the spectral acceleration
value corresponding to this value is a fairly high value, about 3.0 g. The effect of
this situation is clearly seen in Figure 15. When only the horizontal components
of the earthquake were imposed on the building in the X and Y directions at the
same time, no lifting of the insulators was observed as a result of the analyses.
In other words, lifting did not occur in any isolators due to overturning under the
effects of horizontal earthquakes. However, when the vertical component of the
earthquake recording was also imposed on the building in the Z direction, up to
1 mm lifts were observed in all isolators, as shown in Figure 15.

Figure 13. RSN181, H-E06-UP Vertical Component ground acceleration - time record

Figure 14. 5% damped acceleration spectrum of RSN181, H-E06-UP vertical component

128 The Journal of Environment, Urban and Climate