DefinePK

Abstract

The residential and commercial construction demand is on rise worldwide. This development has introduced more critical engineering and architectural applications and innovations. Soft story buildings or towers are a few common examples of these applications. This study presents an inclusive investigation to study the effect of geometric configuration on the seismic response of vertically regular and irregular reinforced concrete frame structures. The main geometric factors will be slenderness ratio, defined as height to width ratio of the structure, and plan aspect ratio, defined as length to width ratio of the structure. The irregular frames will be introduced with the common real life construction feature known as vertical structural irregularities specifically soft story frame cases. The location of irregularity will vary in three locations in the vertical plane viz. bottom, middle and top. The objective of the investigation is to estimate the seismic demand for each slenderness and plan aspect geometric ratio. The variation in geometric ratios involve five slenderness ratios as 1, 1.5, 2, 2.5 and 3 as well as five plan aspect ratios as 1.2, 2.4, 3.6, 4.8 and 6. Response spectrum analysis is undertaken for the seismic response interpretation using STAAD Pro software employing finite element technique. The results indicate that the increase of regular frame slenderness leads to slight increase in shear response but higher displacements and drift. The increase in plan aspect ratio increases the frames shear response significantly with almost convergent displacements. Also the regular and irregular frames of smaller slender ratios exhibit higher lower-story displacements and drifts than the frames with higher slender ratios. The bottom irregular frames appear to be more vulnerable as compared to frames having irregularity at middle and top level.