International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056 Volume: 03 Issue: 09 | Sep-2016 www.irjet.net p-ISSN: 2395-0072 © 2016, IRJET | Impact Factor value: 4.45 | ISO 9001:2008 Certified Journal | Page 1333 STUDY OF SEISMIC BEHAVIOUR OF BUILDINGS WITH FLAT SLAB Dr. M Rame Gowda 1 , Techi Tata 2 1 Professor & Head, Department of Civil Engineering, Adichunchanagiri Institute of Technology, Karnataka, India 2 PG Student, Department of Civil Engineering, Adichunchanagiri Institute of Technology, Karnataka, India ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - The word Dzflat slabdz is better understood as the slab without beams resting directly on supports. In case of flat slab, large bending moment and shear forces develops near the columns. Due to this, stresses are developed leading to cracks in concrete which may be further responsible for the failure of slab. Therefore in order to avoid this, flat slab are usually provided with drop and column head or capitals. Two models are prepared. First model is a commercial building consisting of flat slab with drop and second model is a commercial building consisting of slab without drop. Firstly, the behavior of both buildings were studied and analyzed separately for all seismic zones and then finally, a comparison between both structures was made. Analyses were carried out using Response Spectrum method with the help of ETAB version 15.2.0. In order to study the behaviour, only maximum values were considered for the parameters like Storey Displacement, Storey Shear, Storey Drift, Storey Acceleration and Overturning Moment. From the results generated, it is quite clear that the building consisting of flat slab with drop shows better seismic performance. Key Words: Flat slab, drop, Seismic performance, Response spectrum analysis, ETAB 1. INTRODUCTION Earthquakes are one of the most destructive natural phenomenon and their occurrence is beyond human control. Most of these earthquake are man-made. Thus, we human beings are responsible to provide protective and safety measures to withstand this earthquake to some extent. Human being faced a large number of natural disaster like earthquake, floods, tornadoes, hurricanes and volcanic eruptions from time to time. Though the disaster caused by floods, tornadoes, hurricane and volcanic eruptions are much more severe than those of earthquake, but the occurrence of earthquake are totally unexpected. Most of the earthquake in the present scenario is mainly due to high rise buildings in the developing countries with huge number of population. The disaster caused during the earthquake are not because of the earthquake itself but because of human acts of poorly designed constructed buildings. In the present work, the performance of flat slab with and without drop for various loads at all seismic zones have been studied. 2.1 LITERATURE REVIEW Many Research works has been carried out to know the Seismic response of a flat slab building since from many decades. Flat slab are preferred by both architects and clients due to their aesthetic and economic advantages. Literature survey for the seismic behavior of flat slab buildings has also been concealed. K. S. Sable et al (2012), compared the seismic behavior of multistoried flat slab building and conventional reinforced concrete framed structure. The modelling and analysis of the structure have been performed using STAAD Pro 2007. Certain analysis were also made for the analysis such as the height of the structure was kept 17.5m, 25m, 32.5m, 39.5m and from ground these buildings are of 5 storey, 7 storey, 9 story and 11 story. Zone II was considered for the analysis. The author concluded that natural time period will increase as the height of structure increases for both but it will be same if they are provided with shear wall. As the height of the structure increases, the base shear also increases. The Conventional RCC building has less base shear as compared to the flat slab structure. The flat slab structure has more story drift then that of conventional RCC building. Pradip S. Lande and Aniket B. Raut (2015), carried out a parametric investigation to identify the seismic response of system considering Zone V. They have considered the following elements for their works- (a) building with flat slab, (b) flat slab with parametric beam, (c) flat slab with shear walls, (d) flat slab with drop and (e) conventional building. Analyses were carried out using ETabs nonlinear version 9.7.3 for determining the seismic performance of the structure. They considered G+6 and G+12 storied building. Column size 450mm x 450mm and beam size 230mm x 400mm were considered for G+6 and column size of 650mm x 650mm and beam size 230mm x 500 mm were considered. On the basis of the work carried out, the author concluded that the storey displacement is found to be maximum for flat slab building as compared to conventional RCC building. The maximum storey drift found for G+6 building was 0.04 % of height. Basavaraj and Rashmi B. A (2015), considered G+4 and G+8 storied building for their work. In their model they have also added parameters like perimeter beam, infill walls, shear walls and they have also increased the cross sectional area of the columns. The outer beam and column size provided was