Seismic Analysis

EVALUATION OF SEPERATION spreadhead BETWEEN MULTISTOREY BUILDINGS SUBJECTED TO DYNAMIC seismal LOADDr. G Sridevi1*(0000-0002-5922-3132), Mr. Umesh Biradar 2(0000-0003-0087-9433), Mr. G Sudarshan 3(0000-0002-5129-5465) and , Mr. A Shivaraj 4(0000-0002-7437-1256) 1234 B V Raju constitute of Technology, Narsapur, India arise When structures argon on a lower floor earthquake forces, side by side(predicate) structure may collide with all(prenominal) other(a) due to disparate fighting(a) characteristics. When structure reels out of phase and free hurly burly among mental synthesiss argon non adequate to accommodate their telling motions, this screwister cause sinful damage to the structures and it is know as unstable hammer.Most of the era it is non possible to maintain sufficient dog pound gap amongst bordering buildings. Present work judge the minimal insularity gap required amid high-rise building mock ups considered. Two high-rise building of 10 level and 15 stage are modelled and analysed for dynamic conviction chronicle digest for the EI Centro primer coat motions and tokenish throb gap betwixt buildings has been discussed.Keywords seismic hammer, RC build, ETABS, Time History psycho psychoanalysis.INTRODUCTIONBecause of expanding population and defeat esteems, structures are being built to closure to each other. During a quake it is expect that, they will pound against each other. This repeat collision activity is referred as seismic lbf.. buffeting of structures could use up cause severe damage, as neighbouring structures with various dynamic attributes vibrate out of phase and there is myopic separation gap to accommodate the relative movements of neighboring structures.This highly congested verbal expression system in the metropolitan cities is the major(ip) concern for the seismic pounding. The most simple-minded and viable regularity for controlling the publicize and diminish the harm cause by it is to open up enough separation gap surrounded by the near structures.LITERATUREShehata (2006) examined structure pounding rejoinder and proper seismic hazard profusion technique. Three categories of recorded earthquake lighting are used for input. The effect of come to is examine using linear and nonlinear contact force model for antithetic separation outperforms and compared with nominal model without pounding consideration. And it is give overd that, an increasing gap largeness is likely to be effective to background the effect of seismic pounding.Mizam Dogan et.al (2009) carried stress examinations on outline models for various effect focuses and probe on pounding. It is concluded that pounding forces are not totally absorbable on account of their high esteems but quite an their consequences for structure can be diminish by setting versatile materials between neighboring structures or by beef up basic frameworks.Pushover is a static nonlinear analysis method to estimate seismic morphological deformations. It gives force displacement human relationship of a structure or geomorphologic element. Horizontal load is applied in a specified pattern in increments and for a presumptuousness applied lop force, associated displacement is found until it reaches its maximum skill of deformation.As the narration drift increases the columns are subjected to additional moment leading to the ill fortune of the structure. A B Kawade et.al studied the borderline gap to be provided between the next buildings using push over analysis. retort spectrum analysis was carried out by fetching the data of EI Centro earthquake on different models. The extends indicated that the acceleration and clip force produced because of pounding varies with the storey height and peak storey drift depends on the ground ignition characteristics.The effect of pounding is incurd to be much than predominate when floor levels of adjacent building are different const ructing disassociate buildings with equal floor heights is adept of viable solutions to prevent seismic structural pounding. It was also observed that the separation distance to be maintained increases with the increase in peak ground acceleration values.Jeng-Hsiang Lin et.al (2002) investigated the seismic pounding probability of buildings in the capital of Taiwan metropolitan area.Detailed procedures of the analytical method are presented. And concludes that pounding probability of adjacent buildings is found to be significantly affected by the natural period of individualist buildings and the period ratio of the adjacent buildings. out-of-pocket to the lack of proper treatment of the shudder phases of adjacent buildings, it is found that the method used in the current Taiwan build Code (TBC97) provides poor estimates for the required building separation distance and produces a non-uniform stake for all the cases investigated in this study.MOTIVATION AND OBJECTIVES OF STUD YTo Study the ever-changing deportment of Tall Structures.To Evaluate seismic lb Effect of attached Buildings with precondition of plumb Geometrical Irregularity.To Study the work out of Shear Walls on seismal Pounding Effect.MODEL DESCRIPTIONIn Present Study Total 3 Models have been Modelled to Evaluate slashing Behaviour of High Rise Buildings by Considering Vertical Geometrical Irregularities.Model 1 A be after which consists adjacent multi storey buildings one is 10 report and the other one is 15 invoice with a separation of 100mm with Masonry infill walls.Model 2 A Plan which consists adjacent multi storey buildings one is 10 Storey and the other one is 15 Storey with a separation of 100mm in this particular model all infill walls are modelled and designed as shear walls.-47625012700Fig 1 Plan expectation of the Buildings1219200176530Fig 2 Isometric View of ETABS Model1104900191770Fig 3 Elevation of ETABS ModelMETHODOLOGYThe principle objective is to evaluate the effects of seismic pounding between two closely spaced multi-storey buildings, to meet the minimum seismic gap between the buildings, modelling is done to study the solution of buildings under pounding during EI Centro earthquake.In order to observe pounding effect between adjacent buildings, two RC buildings of 10 and 15 storey are considered. Both buildings have been modelled and analysed in ETABS 2015 software. Based on the analysis results the clear up separation distance is provided. all 3 models have been analysed for nonlinear time history analysis to study dynamic behavior of buildings.The output results were obtained.In Time History abridgment the ground motion records are given as input. The time history analysis has the ability to perform linear as well as non linear analysis . The ability of this method to account for two-way effects by applying three components of ground motion helps in predicting the response more precisely. In a Linear analysis, it is fak e that the displacement of whole structure does not exceed elastic limit under the application of design forces. when the structure deforms more than elastic limit, non linearity of the structure in terms of geometry or material are to be considered.Bureau of Indian Standards distinctly gives in its code IS 4326, that a judicial separation distance is to be provided between buildings to annul collision during an earthquake. The IS code provisions are mentioned in following Table.Fig 4 shift Width for Adjoining Structure as per IS 4326 ( Table 1 )Table 1 unstable ParametersSoil Type MediumResponse Reduction Factor, R 5Importance Factor, I 1.5Zone IVTable 2 Material PropertiesConcrete cube strength, fck30 N/mm2 (M30)Characteristics strength of reinforcing steel, fy415N/mm2(Fe 415)Modulus of elasticity of concrete, E 29.5 kN/mm2Unit weight of concrete 25 kN/m3Table 3 Sectional PropertiesName of the Element Size in mmBeam 1 three hundred * 400Beam 2 300 * 500Beam 3 350 * 600C olumn 1 300 * 300Column 2 300 * 400Column 3 300 * 500Column 4 300 * 600Column 5 300 * 700Slabs 125Exterior walls,w1 300Interior walls,w2 230 6. RESULTS AND DISCUSSIONS Dynamic Time History Analysis of considered models have been performed in ETABS Software. EI Centro Ground Motions were considered as stimulus Data for Analysis.Effect of Pounding is studied with a reference to storey displacement. The Storey Height Vs Storey transformation graph has been plotted to understand the dynamic behaviour of Structure.Fig 2 Storey Displacement ignore for Model 1Fig 2 Storey Displacement Curve for Model 2Fig 3 Storey Displacement Curve for Model 37. finis Stiffness of building has got a nifty influence on displacements in individual directions.In Model I separation gap between adjacent buildings are 100 mm. Displacement observed was 509.883 mm in X direction and 31.881 mm in Y direction. When masonry wall are replaced with shear wall, lateral displacement has trim back in consider able amount to 36.74 % and 80.8 % in X and Y direction respectively.Effect of pounding can be reduced by providing safe separation gap. By the result of Model I we can conclude that minimum safe separation gap between building is 540 mm.Stiffness of building can be enhanced by adopting shear wall to reduce the pounding effectREFERENCESA.B. Kawade , Mr. Abhijeet A. Sahane unstable pounding effect in building Amrutvahini college of engineering, Sangamner.Alireza M.Goltabar.R, Shamstabar Kami, A.Ebadi, (2008) Analyzing the effective parameters in Pounding Phenomenon between Adjacent Structure due to earthquake,The 14th World Conference on Earthquake Engineering, pp. 12-17, Beijing, China.Diego Lopez Garcia, (2004)Separation between Adjacent nary(prenominal)linear Structures for Prevention of seismic Pounding, 13th World Conference on Earthquake Engineering Vancouver, B.C., Canada, Paper No. 478.Jeng-Hsiang Lin, Cheng-Chiang Weng, (2002)A Study on Seismic Pounding Probability of Bui ldings In capital of Taiwan Metropolitan Area, Journal of the Chinese Institute of Engineers, Vol. 25, No. 2, pp. 123-135.K.Kasai, V.Jeng, P.C.Patel J.A.Munshi Seismic Pounding Effects Survey and Analysis Illinois Institute of Technology, Chicago,USA.Mizam Dogan and Ayten Gunaydin, (2009)Pounding of Adjacent RC Buildings During Seismic laden, Journal of Engineering and Architecture, Vol XXII, No 1.Raja Rizwan Hussain et.al. (2013)Non-linear FEM Analysis of seismic Induced Pounding between Neighbouring Multi-Storey Structures, Latin American Journal of solids and structures, pp. 921-939.Shehata E. Abdel Raheem, (2006)Seismic Pounding between Adjacent Building Structures, Electronic Journal of structural Engineering, Vol. 6, pp.66-74.Susendar Muthukumar and Reginald DesRoches, (2006)A Hertz contact model with non-linear damping for pounding simulation, Earthquake Engineering and Structural Dynamics, Vol.35, pp.811-828.Weng Dagen, Li Tao Bashar Alfarah, Fransisco Lopez-Almansa (201 7)Non linear time history analysis of a base obscure RC building in shanghai founded on soft soil Tongji University, Technical university of catalonia, paper No. 2634.