SEISMIC RESPONSE OF RC FRAME STRUCTURE WITH SOFT STOREY

S.Zubair Ahmed, K.V.Ramana, Ramancharla Pradeep Kumar

Abstract: Multistoried buildings with open ground floor are inherently vulnerable to collapse due to earthquake load, their construction is still widespread in the developing nations due to social and functional need for provide car parking space at ground level. Engineering community warned against such buildings from time to time. Along with gravity load structure has to withstand to lateral load which can develop high stresses which leads to destruction of buildings. In this case study R.C.C. building is modeled and analyzed in three cases. I) Model with no infill wall (Bare Model). II) Model with bottom storey open. III) Model with steel bracing system at bottom storey. Dynamic analysis of the building models is performed in ETABS. The performance of the building is evaluated in terms of Storey Drifts, Lateral Displacements, Lateral Forces, Storey Stiffness, Base shear, Time period, Torsion. It is found that steel braced system significantly contributes to the structural stiffness and reduces the maximum inter story drift, lateral displacement of R.C.C building. The results of bare frame, steel braced system and open bottom storey frame are discussed and conclusions are made.

Keywords: Storey Drifts, Storey Stiffness, bare frame.

DOI: https://doi.org/10.15623/ijret.2014.0309027