Analysis of Moment Resisting Reinforced Concrete Frames for Seismic Response Reduction Factor
Prof. Amit A. Kusanale1, Mr. Keshav Ramdas Manerikar21 Assistant Professor, Department of Civil Engineering, P.V.P.I.T. Budhgaon, Sangali, India
2PG Student, Department of Civil Engineering, P.V.P.I.T. Budhgaon, Sangali, India
Abstract - Earthquake is the maximum vital factor to bear in mind whilst designing a building is earthquakes. For the duration of earthquakes, systems vibrate. Wind forces, earthquakes, machine vibrations, and lots of other elements can purpose vibrations. These vibrations can now and again purpose structural harm, especially below sturdy earthquake excitations. Via the use of dampers severe damage can be averted. The idea of the viscous damper is to take in shocks and vibrations from the shape. However,themaximumcrucial is the place of the dampers that is a primary consideration. The viscous damper is taken into consideration the passive manipulate machine used to use up and take in strength prompted at some stage in earthquakes due to earthquakes. The principle reason of the utility ofdampersisto decoratethe stiffness and stability of the shape and make the shape earthquake resistant. The present look at is targeted at the study of the seismic conduct of buildings with dampers and evaluating seismic responses to displacement and different elements
Key Words: (Viscous Dampers, Visco- Elastic Damper, Displacement
1. INTRODUCTION
Anearthquakeisaneffectiveshakingoftheearth'ssurface thatcanbedeadlytohundredsofpeopleandcausesevere harm. They may be delivered on through the unexpected releaseofelectricityfromtectonicplatemovementswithin theEarth'scrust. Seismic wavesare the mannerby which this strength is discharged. The most excessive and unanticipatedherbalcalamitiesareearthquakes.Insidethe worstscenario,themassiveamountofenergyproducedin the course of an earthquake might also result in serious injuryorthedestructionofvitalstructures.Civilstructures like excessive-rise homes, skyscrapers, and lengthy span bridgesaredesignedwithmoreflexibilityasaresultofthe speedyfinancialdevelopmentandcontemporarygeneration, which increases their susceptibility to external excitation. Consequently,thesebendysystemsarevulnerabletobeing uncoveredtoextraordinarilyexcessivedegreesofvibration insidetheoccasionofarobustwindorearthquake.Withthe intentiontoholdsuchcivilprojectsfromsufferingsizeable harm,thereactionreductionofcivilsystemsfortheduration ofdynamicloadssuchmassiveearthquakesandexcessive winds has come to be a crucial topic in structural engineering. The forces triggered at some point of the
earthquakesneedtoberesistedbywayofthesystemswith outsufferinganyimportantstructuraldamage.Allsystems havetobedesignedtowithstandlateralhundredsinseveral ways.Themaximumcommonplacelateralmassesresisting systemsaremomentframes,shearwallandbracedframe. Passiveelectricitydissipatingstructuresarealsousedasan alternativetoseismicisolationwhichprotectsthesystemsin opposition to the earthquakes. The application of such structures enhances the power soaking up potential of structures.
Themaximumnotunusualtypesofthesestructuresconsist of fluid viscous dampers, friction dampers, tuned mass dampersandsteeldampers.Inthepresentexamineoneof the passive power dissipating gadgets is used and the seismicbehaviouroftheconstructingisstudied.
1.1 VISCOUS DAMPERS
Viscousdampers,additionallycalledseismicdampers, are hydraulic additives that diffuse kinetic strength precipitated for the duration of earthquakes and soften structuralcollisions.Theymaybeadaptabledevicesthatcan be made to provide for every managed and out of control dampeningofsystemstoprotectthemfromearthquake.
1.2 VISCOELASTIC DAMPER
Viscoelastic(VE)dampershavebeeneffectivelyfusedin various tall structures as a reasonable vitality scattering frameworktosmotherwind-andquakeinitiatedmovement of building structures. This sort of damper disperses the structure'smechanicalvitalitybychangingoveritintoheat.
Afewfactors,forexample,encompassingtemperatureand thestackingrecurrencewillinfluencethepresentationand subsequently the viability of the damper framework. VE dampershavehadtheoptiontoexpandthegeneraldamping of the structure essentially, subsequently improving the generalexecutionofpowerfullytouchystructures.
To study and evaluate seismic responses such as displacement.Acceleration.
To study Time History utilizing VD and VED in structures
3. METHODOLOGY
More than one-story structures come under the multi Stages of freedom systems. In multi tiers of freedom Structures the deformation of an entire shape cannot be related by using a single displacement, more than one Displacementcoordinatesarewantedtobecomeawareof thedisplacedstructures.
3.1 Methods of analysis
1.3 FLUID VISCOUS DAMPER
Fluid viscous dampers are one of the passive energy vanishing devices, for controlling vibration caused in structureandmechanicalsystems.Inmilitaryandaerospace industry they use extensively these type of dampers from past years now a days these are used in the buildings to controlthevibrationscausedbywindandearthquakes.One of the greatest unique capacity of the dampers is it will togetherdecreasesboththestressanddeflectionwithinthe structuresubjectedtotransient.Thisisbecausethedampers vary its force only with the velocity, due to flexing of the structure the response that is permanently out of phases with the stresses. To vanishes the energy in the building thesedampersareusedbecausethesedampersarevelocity dependent. To reduce the responses in the building these effective damping should be done by using these type of dampers.FVDsarefrequencyindependentdeviceswithouta stiffnesscomponent.
2. SCOPE AND OBJECTIVE
2.1 Scope:
ToperformtheseismicanalysisofmultistoreyRCCbuilding (G+8)withandwithoutdampers
2.2 Objective:
Tostudythebehaviorofstructurewithandwithout dampers
3.1.1 Equivalent static method: An equivalent static method is also referred to as an equal lateral pressure method.Seismicanalysisonabuildingiscarriedoutonthe assumption of the horizontal pressure is just like the dynamicloading,insidethetechniquedurationsandshapes ofhighermodesofvibrationaren'trequiredsotheeffortfor theevaluationismuchless,besidesthefundamentallength. Thebasesheariscalculateddependingonthemassofthe shape, its fundamental intervals of vibration, and shapes. Firstofallthebottomsheariscalculatedforanentireshape then alongside the peak of the building distribution is executed.Ateachgroundlevel,thelateralforceacquiredis allotted to every structural detail. This method is usually followedforanextremelylowtomediumpeakconstructing.
3.1.2 Response spectrum method: Reaction spectrum techniqueislikewisecalledasamodalTechniqueormode superposition technique. This method is utilized in a structure where the modes will have an effect on the Reactionofshapeapartfromthefundamentaloneespecially this technique used for a dynamic analysis of a Building whichcanbeasymmetricalinplanorirregularityinareas.In case of multi storied homes to find the Forces and displacements brought about because of medium variety Earthquakemovementthistechniqueisusedforevaluation.
For the study purpose reinforced concrete structures are considered, having G+8 stories of height3.1meachFloor.
R.C.C.regularStructuredesignonE-tabSoftware.
The number of storey and floor height is kept constant for all models in order to get consistent results
Tounderstandthebehaviourunderseismicloads theloadsareappliedasperIS1893:2002.
Designthestructurewithandwithoutdampers.
3. RESULTS AND CONCLUSION
Theresultsareusedtoconcludethesuitabilityofdampers
3.1DisplacementofStorey:
3.1.1 Storey Response Displacement in mm in xdirection for G+ 8
Tableno1:StoreyResponseDisplacement
a) The graph shows displacement v/s height of the building for G + 8 building with dampers applied at alternatestoreys.
b) ThepermissibledisplacementasperIScodeis(H/500) i.e,(24800/500)=49.6mm
c) Themaximumdisplacementobtainedis25.62mminXdirection.
d) The displacement obtained was 49.6 mm without dampers and with the application of dampers the displacementhasbeenreducedto25.62mm.
e) Application of viscous dampers have reduced the displacementby42%
3.1.2 Storey Response Displacement in mm in xdirection for G+ 12
a) The graph shows displacement v/s height of the building for G + 12 building with dampers applied at alternatestoreys.
b) ThepermissibledisplacementasperIScodeis(H/500) i.e,(37200/500)=74.4mm
c) Themaximumdisplacementobtainedis57.45mminXdirection.
d) The displacement obtained was 106.4 mm without dampers and with the application of dampers the displacementhasbeenreducedto57.45mm.
e) Application of viscous dampers have reduced the displacementby45.15%
4. CONCLUSION
a) Thestructureevaluatedwiththeapplicationofdampers tobeefficientandviscousdamperscanserveasbetter energydissipatingdevice.
b) Itcanbeconcludethat,withtheapplicationofviscous damperstheseismicperformanceofthestructurescan beimprovedagainstearthquakes.
c) Non-Lineardynamicanalysisshowstheactualresponse ofthestructuresubjectedtoearthquakes.
d) InG+8buildingwiththeapplicationofviscousdampers wecanseeareductionofdisplacementby42%.
e) In G+10 building with the application of Viscous dampers we can see a reduction of displacement by 45.15%
f) ApplicationofViscousdamperssignificantlyincreases thestabilityandstiffnessofthestructures.
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BIOGRAPHIES
First Author:MrAmitA.Kusanale, AssistantProfessor, DepartmentofCivilengineering, P.V.P.I.T,Budhgaon, Sangali, Maharastra
Second Author:MrKeshavR.Manerikar P.GStudent, DepartmentofCivilengineering, P.V.P.I.T,Budhgaon, Sangali, Maharastra
