Vertical floor spectra in low- and mid-rise elastic RC moment resisting frame buildings: Fid-Bau Portal

Vertical floor spectra in low- and mid-rise elastic RC moment resisting frame buildings

Mazloom, Shahabaldin / Assi, Rola

Highlights • Quantification of the amplification of the vertical floor spectral acceleration (FSAV) along the height and at different locations on a floor of typical RC moment-resisting frame buildings was demonstrated. • Conclusions and insights into the effect of the out-of-plane flexibility of slabs on FSAV were highlighted. • Equations were proposed to derive FSAV corresponding to the input vertical ground spectral acceleration (GSAV). • The approach proposed by AC 156 provisions to derive FSAV could be generally applied at the rigid nodes of the supporting floor.

Abstract To examine how floor spectral accelerations affect the design force of flexible Non-Structural Components (NSCs), the present study discusses the estimation of floor response spectra resulting from strong vertical seismic motion. 3-, 6-, 9- and 12-storey reinforced concrete buildings with moderately ductile moment-resisting frame systems, designed in accordance with the National Building Code of Canada were selected for this research. 65 sets of historical records relating to 31 severe earthquakes from across the world were used to analyze the linear behavior of these structures. A constant amplification of the Vertical Floor Spectral Acceleration (FSAV) was observed along the building height. This amplification was noticeably elevated for slab nodes, especially at the center of the interior slab and in shorter buildings. Furthermore, the vertical component of the earthquake had a greater impact at shorter periods, since the maximum vertical acceleration occurred at periods lasting less than 0.35 sec. Finally, equations to estimate FSAV corresponding to the input vertical ground acceleration were proposed for typical code-conforming RC frame buildings.