© 2018 JETIR November 2018, Volume 5, Issue 11 www.jetir.org (ISSN-2349-5162) JETIRK006135 Journal of Emerging Technologies and Innovative Research (JETIR) www.jetir.org 892 Comparison of Regular and Irregular Building Considering Irregularity Using ETABS Nirmal S. Mehta 1 , Tejal D. Patel 2 , Prit P. Suthar 3 , Yash B. Soni 4 , Department of Civil Engineering, U. V. Patel College of Engineering, Ganpat University, India 1,2,3,4 Abstract Irregularities are not avoidable in construction of buildings. However, the behavior of structures with these irregularities during earthquake needs to be studied. Present study represents the behavior of regular and irregular building. In this present study five storey building is considered having 5 bays in both direction with 4meter bay span. The building is modelled in ETABS-2013. In this paper two types of irregularities are considered like re-entrant corner and diaphragm discontinuity. Here four models of diaphragm discontinuity and four models of re-entrant corner are prepared. Four models of diaphragm discontinuity are denoted as D1, D2, D3 and D4, similarly for models of re-entrant corner are denoted as R1, R2, R3 and R4. For analysis purpose various loads are considered like dead load, live load and earthquake load in X and Y-direction. Various loads combinations are considered according to IS-1893:2002. The various parameter like storey drift, storey displacement, torsional displacement and height to weight ratio are considered for comparison. It is observed that storey drift and storey displacement for D1 model as compared to other model in Y-direction is greater than the X-direction. Value of torsional displacement is only existing for model R1 and R4. Torsional displacement is zero for remaining model other than R1 and R4 due to symmetry structure. It is also observed that value of displacement and drift is also depend on the height to weight ratio. Further it is observed that value of displacement and drift decrease as the height to weight ratio increases. Keywords: Re-entrant corner, Diaphragm discontinuity, Storey drift and displacement, Torsional displacement. INTRODUCTION Many buildings in the present scenario have irregular configurations both in plan and elevation, which in future may subject to devastating earthquakes hence it is necessary to identify the performance of the structures to withstand against disaster primarily due to earthquake. Irregularities are not avoidable in construction of buildings; however, the behaviour of structures with these irregularities during earthquake needs to be studied so that adequate precautions can be taken. A detailed study of structural behaviour of the buildings with irregularities is essential for design and behaviour in earthquake. For this study the model having 5 bays in X-direction and 5 bays in Y-direction have been considered for the analysis. The distance between 2 successive grids in both direction is considered as 4m. In the present study, the behaviour of five-storey R.C frame buildings having irregularities confirming to IS 1893 (Part 1): 2002 subjected to an earthquake, are discussed after analyzing in ETABS software. Gravity loads and laterals loads as per IS 1893-2002 are applied on the structure. Dubey and Sangamnerker, 2011 investigated the seismic behaviour of asymmetric buildings. The main objective is to understand different irregularity and torsional response due to plan and vertical irregularity, and to analyses “T”-shaped building while earthquake forces acts. It was observed that the building with the irregularities are prone to earthquake damage [1]. Banginwar, Vyawahare and Modani, 2012 investigated the effect of the building plan configuration on the seismic behaviour of the building by response spectrum method. It was observed that the plan configuration of the structure has the significant effect on the response of the structure in terms of storey drift, displacement and storey shear. It was also observed that building with severe irregularity shows more displacement [2]. Alavi and Rao, 2013 investigated the effect of plan irregular building in high seismic zone. The main objective of their study is to understand the behaviour of the irregular buildings in the high seismic