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Volume: 08 Issue: 01 | Jan 2021 www.irjet.net p-ISSN: 2395-0072

SEISMIC RESPONSE OF MULTI-STOREY BUILDING WITH OBLIQUE COLUMNS

Sridhara K S1 , G V Sowjanya2

1Postgraduate student, Department of Civil Engineering, 2Assistant Professor, Department of Civil Engineering 1,2Sri Siddhartha Institute of Technology, Tumakuru, Karnataka, India --------------------------------------------------------------------*** ---------------------------------------------------------------------Abstract - In recent decades there are more complex arrangement and angle at which it is inclined. If the angle structures that are challenging earthquake theories. The of oblique column varies, there is change in its earthquake involves generating seismic waves which passes performance. Oneofthecharacters thatchangesincase if through earth crest and causes massive damage to the we adopt oblique column is that there will be decrease in existing structures. The densely populated area in which the plan when the angle is below 90 degree and there will be buildings are not perfectly modeled can be called as increase in plan if the angle is above 90 deg. The seismic earthquake prone area where the small earthquake causes performance of the oblique column needs to investigated a disastrous effect. The columns where they are neither foritadoptionina high rise structure.Iftheperformance parallel to each other nor they are exactly vertical are of this type of columns has advantages then it can be known as oblique columns. The specialty of these oblique adopted in construction engineering for yielding better columns is that the angle which is greater than 90 degree results.Theearthquakeforcesareevaluatedbycalculating will have increase in its plan as we move to higher floors the structural response of the building. There are various whereas the angle of column which is less than 90 degree methods of seismic analysis like Pushover method of will have its plan decreased as we move to higher floors. The analysis, static method of analysis, response spectrum of oblique restraint causes coupling action on the principal analysisandtimehistory methodaredoneforbothlinear axes. and non-linear type of analysis. In our study we follow Response Spectrum Method which is a dynamic method In this present study it involves the study of oblique column for analyzing a building. The structure is analyzed by effect on a model which has 30 floors in which Height of building a model in conceptual and these results can be each floor is 3.2m. The width of each bay at base is 7m. The obtained. In a structure minimum 3 modes should be columns are inclined at an angle of 80°, 82.5°, 85°, 87.5°, obtainedwhereinsecondorthirdmodewillbenegligible. 92.5o . Here linear static and dynamic analysis are done and results are obtained. ForthedesignandanalysisofastructureETABSsoftware canbeusedforbothsimpleandforcomplicatedmodels.It Key Words: ETABS, Oblique Columns, Storey shear, consists of codes which are inbuilt. There is a common Storey drift, Storey Displacements, Overturning data base in which procedures and codes are being used. Moment. In this we can recover the material properties, column data and about member forces. According to the design 1. INTRODUCTION codesitconsistsofloadcombinationsthatareinbuiltwith The country economic and technical growth will be thedatabase. indicated bylevel of high-risestructures. Fewercountries 2. LITERATURE REVIEW have made such advancement in their design and have achieved the high standards of living. The appearance of Rohan Singh, Vikas Prabhakar [22](Study of high-rise buildings are more due to various free style of Multistoried buildings with oblique columns) architecture features. The Pacific seismic belt and Europe (2020).Analyzing the behavior of oblique columns was Asia seismic zone are present in China country which is that the main purpose of this study. Since the Oblique developing with densely populated area and has low columns are not conventionally parallel or at right angles seismic capacity building. It has most dangerous seismic toaspecifiedlinetherefore,theyarerotatedorinclinedat area in which the building has to be designed by an angle, resulting in decrease of plan dimensions for consideringearthquakeintensity. oblique column below 90° and for above 90°, there'll be increase in plan dimensions as we reach upper floors. It There has been adoption of a kind of columns called affectsthelateralstiffnessofbuildingandobliquecolumns obliquecolumns incaseofmulti-storiedstructureinstead below 90° have lesser storey shear values. Therefore, ofnormalcolumnsforseismicresistanceinabuilding.Itis analysisiscarriedout byconsideringcolumnsof80°,82°, a type of column where it is not constructed exactly 84°,86°,88°and90°degrees.Thestructureisanalyzedfor vertical. It can be adopted in medium, high and low rise both dynamic and for static loading. Ground motion structures. Oblique columns are unique because of its