Abstract:
It is usually common that buildings were founded on levelled grounds. However, there are a
number of circumstances when this might be impossible or not preferred due to various factors
in construction activities where buildings are getting constructed on uneven grounds of varied
slopes. This change in the level or formation of foundation is proposed to have effect on the
various responses of the buildings to external and internal stresses and forces.
This work analyzes effects on three main seismic responses viz. story displacement, story drift
and base shear of G+5, G+8 and G+11 story building resting on varied sloped with angles of 10
degree, 15 degree and 20 degree in comparison to the responses of the buildings resting on flat
ground. Modeling of the buildings and analysis of seismic responses were performed by using
ETABS 2018.00.
The results of each seismic variable of the building resting on varying sloped ground with the
defined number of stories were presented compared to their corresponding buildings resting on
flat ground. Accordingly, for G+5 building story displacement on sloped ground has decreased
with maximum of 36.64% and base shear has decreased by 15.23% compared to the flat ground..
For G+8 building, story displacement has decreased by 17.87% and base shear has increased
by 16.66% compared to the flat ground. For G+11 building, story displacement has decreased
by maximum of 17.13% and base shear has increased by maximum of 16.38% compared to the
flat ground. Story drift on sloped grounds of all the buildings considered in tis work has
randomly become above and below that of flat ground without any specific pattern in decrement
and/or increment.
Generally, the analysis results indicate that sloped grounds have higher seismic resistance than
flat grounds in case of top story displacement. As the ground slope increases, top story
displacement has been decreased in all cases considered under this study. However, the
maximum base shear effects of sloped grounds were observed to be higher than that of flat
ground. The third variable, story drift of the two lower slopes (10 and 15 degree) were found to
be higher than that of flat ground; whereas, the higher slope had lesser drift effect compared to
flat ground.
