The vertical earthquake effect is calculated automatically for the specified elements using the vertical elastic spectrum specified in 11.9.
Elements to be used in the vertical elastic design spectrum are under user control.
Symbols
D = Dead load
Sav = Design vertical response spectral acceleration
Ev = Vertical seismic load effect
Vertical response spectrum should only apply structures in Seismic Design Categories C, D, E, and F. Determining of vertical response spectrum, Vertical Elastic Design Spectrum (ASCE 7-16) is expressed in ASCE 7-16 Section 11.9.
According to 11.9.3, Design Vertical Response Spectrum, the design vertical response spectral acceleration, Sav, shall be taken as two-thirds of the value of SaMv determined in Section 11.9.2.
The vertical seismic load effect, Ev, shall be determined in accordance with Eq. (12.4-4b) as follows:
where
Sav = design vertical response spectral acceleration obtained from Section 11.9.3
D = effect of dead load
It has been determined that the vertical earthquake effect has an effect on the building behavior as a certain proportion of the horizontal earthquake effect, as a result of the experiments and monitoring the movements of the buildings under earthquakes. According to the regulation, it is calculated in 2 different ways. It is calculated by using the spectrum only for structures in Seismic Design Categories C, D, E, and F.
ASCE gereği düşey deprem etkisi binaların bulunduğu deprem tasarım sınıfına göre belirlendiği için TBDY de yapılan kullanıcının spektrum ile hesap yapılacak elemanları kendinin seçmesi opsiyonu uygun değildir. Ya deprem tasarım sınıfına göre otomatik yapmalıyız. Ya da tüm yapı elemanlarının düşey deprem etkisinin spektrumla belirlenmesi için analiz ayarlarında yeni bir opsiyon açacağız.
Analiz ayarlarında opsiyon açarak tüm yapının düşey deprem hesabının spektrum ile yapılması daha uygun bir çözüm olarak görünüyor.
ETABS’de ayarlarda otomatik olarak düşey deprem etkisi için herhangi bir veri alınmıyor.
In cases where the vertical earthquake effect is calculated with the spectrum, the mode representing the vertical movement on the relevant element should be calculated. Even if the number of modes is sufficient for horizontal earthquake effect, if the relevant mode is not available, the targeted mode number should be increased and the relevant mode should be included in the calculation. Otherwise, internal forces and displacements for vertical earthquakes affecting the element cannot be calculated correctly.