International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 05 | May 2026 www.irjet.net p-ISSN: 2395-0072
PARAMETRIC STUDY ON THE EFFECT OF BUILDING PLAN GEOMETRY ON DYNAMIC RESPONSE OF RC STRUCTURES MODELED IN ETABS
Tarun Kumar Chauhan1 , Mr. Ushendra Kumar2
1Master of Technology, Civil Engineering, Lucknow Institute of Technology, Lucknow, India
2Head of Department, Department of Civil Engineering, Lucknow Institute of Technology, Lucknow, India
Abstract -The seismic performance of reinforced concrete (RC) buildings is significantly influenced by their plan geometry, particularly in structures subjected to dynamic loading. Irregular configurations, often adopted to meet architectural and functional requirements, introduce complexities such as stiffness discontinuity and torsional effects, which adversely affect structural behavior during earthquakes. This study presents a parametric investigation on the effect of building plan geometry on the dynamic response of RC structures using ETABS. Four G+11 building models with different plan configurations rectangular (regular),L-shaped,T-shaped,andU-shaped weredeveloped under identical material properties, loading conditions, and seismicparametersinaccordancewithIS1893 (Part1):2016. Dynamicanalysiswasperformedusingtheresponsespectrum method to evaluate key response parameters, including natural time period, base shear, storey displacement, storey drift, and torsional irregularity. The results indicate that irregular plan geometries lead to increased flexibility, resulting in higher natural time periods, reduced base shear, and significantly greater displacement and drift. Among the modelsstudied,theU-shapedconfigurationexhibitedthemost critical response, with maximum displacement and drift exceeding permissible limits. In contrast, the rectangular model demonstrated the most favorable performance due to itssymmetricstiffnessdistribution.Thefindingshighlightthe importance of considering plan geometry in seismic design and emphasize the need for careful evaluation of irregular structures.
Key Words: Plan geometry; Dynamic response; RC structures; ETABS; Seismic analysis; Torsional irregularity
1. INTRODUCTION
1.1 Background
1.1.1 Importance of Seismic Performance of RC Buildings
Reinforced concrete (RC) buildings constitute a major portion of modern infrastructure, particularly in rapidly urbanizing regions. The seismic performance of such structures is a critical aspect of structural design, as earthquakesimposeunpredictableandtime-varyingforces that can lead to severe damage or collapse. Historical earthquake events have demonstrated that structural
configuration, rather than only material strength, plays a decisive role in determining building performance. Inadequateconsiderationofseismiceffectsoftenresultsin excessive deformation, cracking, and even catastrophic failure. Therefore, ensuring adequate seismic resistance through proper design and analysis is essential for safeguarding life and property. Modern seismic design philosophies emphasize performance-based approaches, wherebuildingsareexpectedtowithstanddifferentlevelsof seismicintensitywithcontrolleddamage(Chopra,2017).
1.1.1.1 Role of Dynamic Analysis
Dynamicanalysisisfundamentalinevaluatingtheresponse ofRCbuildingssubjectedtoearthquakeloading,asseismic forcesareinherentlytime-dependent.Unlikestaticanalysis, dynamicmethodsconsiderinertiaforces,dampingeffects, andhigher-modecontributions,providingamorerealistic representation of structural behavior. Parameters such as natural time period, mode shapes, and damping characteristics govern the response of structures under seismicexcitation.Formulti-storeyandirregularbuildings, dynamic analysis becomes indispensable, as simplified methods fail to capture torsional effects and complex vibration patterns. Consequently, modern design codes recommenddynamicanalysistechniquessuchasresponse spectrum and time-history analysis for accurate seismic evaluation(CloughandPenzien,2003).
1.2 Influence of Plan Geometry
1.2.1
Regular vs Irregular Configurations
Building plan geometry significantly influences the distributionofmassandstiffness,whichinturngovernsthe structural response under seismic loading. Regular configurations are characterized by symmetry and uniformity,leadingtopredictablebehaviorandefficientload transfermechanisms.Incontrast,irregularconfigurations suchasL-shaped,T-shaped,andU-shapedplans introduce discontinuities in geometry that disrupt the uniform distributionofforces.Theseirregularitiesoftenarisedueto architecturalrequirementsbutcanadverselyaffectseismic performance. Studies have shown that irregular buildings tendtoexhibithigherdeformationandstressconcentration compared to regular structures, making them more vulnerableduringearthquakes(PaulayandPriestley,1992).
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 05 | May 2026 www.irjet.net p-ISSN: 2395-0072
1.2.1.1 Torsional Effects and Stiffness Irregularity
Oneofthemostcriticalconsequencesofplanirregularityis thedevelopmentoftorsionaleffects.Theseoccurwhenthere isaneccentricitybetweenthecenterofmassandthecenter ofrigidity,causingthestructuretotwistinadditiontolateral translation. This torsional motion leads to uneven displacementacrossthebuildingplan,increasingdemandon edgecolumnsandstructuralmembers.Stiffnessirregularity further amplifies this behavior by creating non-uniform resistance to lateral forces, resulting in localized stress concentrations. Such effects significantly increase the likelihoodofstructuraldamage,especiallyinbuildingswith pronouncedasymmetryorre-entrantcorners(Kalkanand Kunnath,2006).
1.3 Research Gap
1.3.1 Lack of Systematic Parametric Comparison under IdenticalConditions
Despite extensive research on seismic behavior of RC buildings, many studies lack a systematic parametric frameworkinwhichonlyonevariableisalteredwhileothers remain constant. In most cases, variations in multiple parameters such as height, material properties, and loadingconditions makeitdifficulttoisolatetheeffectof plangeometryondynamicresponse.Thislimitationreduces thereliabilityofcomparativeconclusionsandrestrictstheir applicability in practical design scenarios. A controlled parametric approach is therefore necessary to clearly understandtheinfluenceofplangeometry.
1.3.1.1 Limited Quantitative Comparison across Plan Shapes
Another significant gap in existing literature is the lack of comprehensive quantitative comparison among different plangeometries.Whileseveralstudiesqualitativelydiscuss the adverse effects of irregularity, few provide detailed numericalcomparisonsofkeyresponseparameterssuchas displacement,drift,andtorsion.Thisabsenceofquantitative benchmarkslimitstheabilityofengineerstomakeinformed design decisions. A detailed comparative analysis under consistentmodelingconditionsisessentialtoaddressthis gapandenhancetheunderstandingofstructuralbehavior.
1.4 Objectives
1.4.1 Comparison of Dynamic Response of Different Plan Geometries
The primary objective of this study is to evaluate and compare the dynamic response of RC buildings with differentplangeometriesunderseismicloading.Byadopting a parametric approach, the study aims to isolate the influenceofplanconfigurationandassesshowvariationsin geometry affect structural performance. This comparison
provides valuable insights into the relative behavior of regularandirregularstructures.
1.4.1.1 Evaluation of Response Parameters
To achieve the above objective, key dynamic response parametersareanalyzed,includingnaturaltimeperiod,base shear, storey displacement, storey drift, and torsional response. The natural time period reflects the overall stiffness of the structure, while base shear represents the total seismic force acting at the foundation level. Storey displacementanddriftarecriticalindicatorsofdeformation demandandpotentialdamage,whereastorsionalresponse highlights the degree of rotational behavior due to plan irregularity. These parameters collectively provide a comprehensiveassessmentofseismicperformance(Chopra, 2017).
2. LITERATURE REVIEW
2.1 Dynamic Analysis of RC Structures
2.1.1 Fundamentals (Mass, Stiffness, Damping)
Dynamicanalysisisessentialforunderstandingthebehavior of reinforced concrete (RC) structures subjected to earthquake loading, as seismic forces vary with time and induceinertiaeffectsthroughoutthestructure.Theresponse of a building under such loading is primarily governed by threefundamentalproperties:mass,stiffness,anddamping. Massdeterminesthemagnitudeofinertiaforcesgenerated duringgroundmotion,whilestiffnesscontrolstheresistance offered by the structure against deformation. Damping representsthemechanismthroughwhichvibrationalenergy isdissipated,therebyreducingtheamplitudeofoscillations. Theinteractionoftheseparametersdefinesthenaturaltime periodandmodeshapesofthestructure,whicharecritical inpredictingseismicresponse.Accurateestimationofthese properties is therefore necessary for reliable dynamic analysisandsafestructuraldesign(Chopra,2017).
2.1.1.1 Significance in Seismic Response Evaluation
Inmulti-storeyRCbuildings,especiallythosewithirregular configurations,higher-modeeffectsandtorsionalbehavior significantly influence the overall response. Dynamic analysis methods such as response spectrum and timehistory analysis capture these complex interactions more effectivelythanstaticapproaches.Thedistributionofmass and stiffness along the height and plan of the building determineshowseismicforcesaretransferredandresisted. Asaresult,anyirregularityinthesepropertiescanleadto amplificationofdisplacementandstressincertainregions, making dynamic analysis indispensable for realistic performanceassessment(CloughandPenzien,2003).
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 05 | May 2026 www.irjet.net p-ISSN: 2395-0072
2.2
Effect of Plan Geometry
2.2.1
Behavior of L, T, and U-Shaped Structures
Plan geometry plays a crucial role in defining the seismic behavior of RC buildings. Regular rectangular structures generallyexhibituniformdistributionofmassandstiffness, resulting in stable and predictable response under earthquake loading. In contrast, irregular plan configurations such as L-shaped, T-shaped, and U-shaped buildingsintroducediscontinuitiesingeometrythatdisrupt theflowofforces.L-shapedbuildingsarecharacterizedby re-entrantcorners,whichcreatestressconcentrationzones and reduce lateral stiffness. T-shaped buildings exhibit asymmetrical stiffness distribution, leading to uneven deformation patterns. U-shaped buildings, being highly irregular, possess significant eccentricity and are particularly vulnerable to excessive deformation and instability. These variations in behavior highlight the importanceofconsideringplangeometryduringstructural design(PaulayandPriestley,1992).
2.2.1.1
Torsional Irregularity
Torsional irregularity is one of the most critical effects associatedwithirregularplangeometry.Itariseswhenthere is an offset between the center of mass and the center of rigidity,causingthestructuretoundergorotationalmotion in addition to lateral translation. This torsional response resultsindifferentialdisplacementacrossthebuildingplan, with edge elements experiencing significantly higher demand.Theseverityoftorsionincreaseswiththedegreeof irregularity and eccentricity, leading to inefficient load distributionandpotentialstructuraldamage.Buildingswith pronouncedtorsionalirregularityrequiredetaileddynamic analysisandspecialdesignconsiderationstomitigatethese adverseeffects(KalkanandKunnath,2006).
2.3 Previous ETABS-Based Studies
2.3.1
Comparative Findings
With the advancement of computational tools, several researchers have utilized ETABS software to study the seismic behavior of RC buildings with different plan geometries.Thesestudieshaveconsistentlydemonstrated that irregular configurations exhibit higher displacement, drift, and torsional response compared to regular rectangularbuildings.TheabilityofETABStomodelthreedimensional structures and perform code-based dynamic analysis has enabled accurate comparison of structural performance under identical loading conditions. Comparativeinvestigationshaveshownthatasthedegreeof irregularityincreases,thestructuralresponsebecomesmore complex and less predictable, emphasizing the need for detailedanalysis.
2.3.1.1
Trends Observed
Common trends observed across ETABS-based studies indicatethatrectangularbuildingsperformbestintermsof seismic response, exhibiting minimum displacement and drift. L-shaped and T-shaped buildings show moderate irregularity effects, with increased deformation and torsional response. U-shaped buildings consistently demonstrate the most critical behavior due to their high eccentricityandstiffnessdiscontinuity.Thesetrendsconfirm that plan geometry has a direct and significant impact on dynamic response parameters, and that increasing irregularity leads to deterioration in seismic performance (Sapkotaetal.,2022).
3. METHODOLOGY
3.1 Research Framework
3.1.1
Parametric Analytical Approach
Thepresentstudyadoptsaparametricanalyticalframework to systematically evaluate the influence of building plan geometry onthedynamicresponseofreinforcedconcrete (RC)structures.Inthisapproach,asetofbuildingmodelsis developedandanalyzedunderidenticalconditions,ensuring consistency in material properties, loading, and boundary conditions.Theobjectiveofusingaparametricmethodisto isolatetheeffectofasinglevariable plangeometry while eliminating the influence of other factors. This enables a directandmeaningfulcomparisonofstructuralperformance acrossdifferentconfigurations.
3.1.1.1
Geometry as the Only Variable
To ensure the reliability of the comparative analysis, plan geometry is treated as the sole variable in the study. All other parameters, including building height, member dimensions,materialcharacteristics,andloadingconditions, arekeptconstant.Thiscontrolledmodelingstrategyensures thatanyvariationobservedindynamicresponseparameters isexclusivelyduetodifferencesinplanconfiguration.Such an approach enhances the accuracy of conclusions and providesclearinsightsintotheroleofgeometryinseismic behavior.
3.2 Description of Building Models
3.2.1
Model Configurations
Fourdistinctbuildingmodelsareconsideredinthisstudyto represent both regular and irregular plan geometries commonlyencounteredinpractice.Thesemodelsincludea rectangular configuration (M1) as the reference case, and three irregular configurations L-shaped (M2), T-shaped (M3),andU-shaped(M4).Eachmodelrepresentsadifferent degree and type of plan irregularity, allowing for a
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 05 | May 2026 www.irjet.net p-ISSN: 2395-0072
comprehensive evaluation of their impact on dynamic response.
3.2.1.1
Structural Significance of Configurations
Therectangularmodelexhibitssymmetryinbothdirections, resulting in uniform distribution of mass and stiffness. In contrast,theL-shapedmodelintroducesre-entrantcorners, leadingtostressconcentrationandstiffnessdiscontinuity. TheT-shapedconfigurationcreatesasymmetryinstiffness distribution,whiletheU-shapedmodelrepresentsahighly irregularplanwithsignificanteccentricity,makingitmore susceptible to torsional effects. These configurations are selected to capture a wide range of structural behaviors underseismicloading.
3.3 Common Structural Parameters
3.3.1
Building Characteristics
All building models are designed as G+11 multi-storey RC moment-resistingframestructurestorepresenttypicalmidrisebuildings.Thestoreyheightismaintainedat3meters for each level, resulting in a total building height of 36 meters. This uniformity ensures that differences in structuralresponsearenotinfluencedbyheightvariation.
3.3.1.1
Material Properties
Thestudyadoptsstandardconstructionmaterials,including M30 grade concrete and Fe500 grade reinforcing steel. Thesematerialsarewidelyusedinmodernconstructiondue to their adequate strength and durability. By maintaining consistentmaterialpropertiesacrossallmodels,thestudy ensures that variations in dynamic response are solely attributedtodifferencesinplangeometry.
3.4 Loading and Seismic Parameters
3.4.1
Seismic Design Considerations
SeismicloadingisdefinedinaccordancewithIS1893(Part 1):2016toensurepracticalrelevanceandcompliancewith Indian design practices. The building is assumed to be locatedinSeismicZoneIII,representingmoderateseismic risk. Appropriate values of importance factor, response reductionfactor,anddampingratioareadoptedaspercodal recommendations.
3.4.1.1
Response Spectrum Analysis
Dynamicanalysisiscarriedoutusingtheresponsespectrum method, which estimates peak structural response under earthquake excitation. The response spectrum is defined based on codal provisions, incorporating soil type and dampingcharacteristics.Thismethodiswidelyacceptedfor seismic analysis of multi-storey buildings and provides reliableresultsforcomparativestudies.
3.5 ETABS Modeling Procedure
3.5.1
Three-Dimensional Modeling
All building models are developed using ETABS software, whichallowsaccuratethree-dimensionalrepresentationof structuralelements.Themodelingprocessincludesdefining gridsystems,storeylevels,materialproperties,andsection dimensions. Structural elements such as beams, columns, and slabs are modeled to simulate realistic building behavior.
3.5.1.1
Boundary Conditions and Mass Definition
Arigiddiaphragmisassignedateachfloorleveltorepresent in-plane stiffness of slabs, ensuring proper distribution of lateral forces. The base of the structure is assumed to be fixed, which restricts both translational and rotational movement at the foundation level. The seismic mass is defined based on dead load and a portion of live load, as recommended by seismic design codes. Accurate mass definitionisessentialforrealisticestimationofinertiaforces duringdynamicanalysis.
3.6 Dynamic Analysis
3.6.1
Modal Analysis
Modalanalysisisperformedtodeterminethefundamental dynamicpropertiesofthestructure,includingnaturaltime periodsandmodeshapes.Thenaturaltimeperiodreflects the flexibility and stiffness of the building, while mode shapesdescribethedeformationpatternsduringvibration. These parameters form the basis for further dynamic analysis and are essential for understanding structural behaviorunderseismicloading.
3.6.1.1
Response Spectrum Analysis
Response spectrum analysis is conducted using codal spectraldatatoevaluatethemaximumexpectedresponseof the structure. The analysis involves combining modal responsesusingstandardtechniquessuchasSquareRootof SumofSquares(SRSS)orCompleteQuadraticCombination (CQC). These methods account for the contribution of multiple vibration modes and provide a comprehensive assessmentofseismicresponse.
3.7 Response Parameters Evaluated
3.7.1
Primary Dynamic Response Parameters
The evaluation of structural performance is based on key dynamic response parameters, including natural time period, base shear, storey displacement, storey drift, and torsional irregularity. Each of these parameters provides insight into different aspects of structural behavior under seismicloading.
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3.7.1.1 Engineering Significance of Parameters
Thenaturaltimeperiodindicatestheglobalstiffnessofthe structure,whilebaseshearrepresentsthetotalseismicforce actingatthebase.Storeydisplacementreflects thelateral movement of the building, and storey drift measures the relativedeformationbetweenconsecutivestoreys,whichis criticalforassessingdamagepotential.Torsionalirregularity evaluates the extent of rotational motion caused by plan asymmetry. Together, these parameters enable a comprehensive comparison of the dynamic response of differentplangeometriesandformthebasisforevaluating theirseismicperformance.
4. RESULTS AND DISCUSSION
(This section presents a detailed interpretation of the dynamic response of RC buildings with different plan geometriesbasedonETABSanalysis.)
4.1 Natural Time Period
4.1.1 Fundamental Time Period Results
The natural time period is a key indicator of the dynamic characteristicsofastructure,reflectingitsstiffnessandmass distribution. The values obtained from modal analysis for differentbuildingmodelsarepresentedinTable1.
4.2 Base Shear
4.2.1 Base Shear Results
Baseshearrepresentsthetotal seismic forceactingatthe baseofthestructureandis influencedbythenaturaltime period. The values obtained from response spectrum analysisaresummarizedinTable2.
Table 2: Base Shear for Different Models
4.3 Storey Displacement
4.3.1 Maximum Storey Displacement Results
Storeydisplacementrepresentsthelateralmovementofthe structureunderseismicloading.Themaximumdisplacement valuesobservedatthetopstoreyaregiveninTable3.
Table 3: Maximum Storey Displacement
4.1.1.1
Discussion on Time Period
Theresultsindicateaclearincreasingtrendinnaturaltime period with increasing plan irregularity. The rectangular model (M1) exhibits the lowest time period due to its symmetrical configuration and uniform stiffness distribution. In contrast, the L-shaped, T-shaped, and Ushaped models show progressively higher time periods, indicatingreducedstiffnessandincreasedflexibility.TheUshapedmodel(M4)hasthehighesttimeperiod,confirming thathighlyirregularconfigurationstendtobemoreflexible and susceptible to larger deformations under seismic loading.
4.5 Torsional Irregularity
4.5.1 Observed Torsional Behavior
Torsionalirregularityisevaluatedbasedonthevariationin displacementacrossthebuildingplan.Theresultsindicate thattorsionaleffectsareminimalintherectangularmodel andincreasesignificantlyinirregularconfigurations.
4.5.1.1 Discussion on Torsion
The U-shaped model exhibits the highest torsional irregularity due to significant eccentricity between the
Table 1: Natural Time Period of Different Models
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
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center of mass and center of rigidity. This results in rotational motion under seismic loading, causing uneven displacement distribution and increased demand on edge structuralelements.TheL-shapedandT-shapedmodelsalso show noticeable torsional effects, though less severe than the U-shaped configuration. Torsional irregularity is a criticalfactorcontributingtostructuraldamageinirregular buildings.
4.6 Comparative Performance
4.6.1 Overall Structural Performance Comparison
A comparative assessment of all models highlights clear differencesinseismicperformancebasedonplangeometry. Therectangularmodelconsistentlyperformsbetteracross allresponseparameters,includinglowerdisplacement,drift, andtorsionaleffects.
4.6.1.1 Best and Worst Performing Models
Amongtheconfigurationsstudied,therectangularmodelis identified as the best-performing structure due to its symmetryanduniformstiffnessdistribution.Incontrast,the U-shaped model is the worst-performing configuration, exhibiting maximum displacement, drift, and torsional irregularity. These findings confirm that increasing plan irregularity adversely affects the dynamic response of RC buildingsandshouldbecarefullyconsideredduringdesign.
5. CONCLUSIONS
Thepresentstudyinvestigatestheinfluenceofbuildingplan geometryonthedynamicresponseofreinforcedconcrete (RC) structures through a systematic parametric analysis usingETABS.Fourbuildingconfigurations rectangular,Lshaped, T-shaped, and U-shaped were analyzed under identical structural and seismic conditions to isolate the effectofgeometry.Theresultsclearlydemonstratethatplan geometry plays a crucial role in governing seismic performance.
The rectangular model exhibited the most favorable behavior,withthelowestnaturaltimeperiod,displacement, andstoreydrift,indicatinghigherstiffnessanduniformload distribution. In contrast, irregular configurations showed progressively adverse performance. The U-shaped model recorded the highest natural time period, reflecting increased flexibility, along with maximum storey displacementanddrift,whichexceededpermissiblelimitsas perIS1893(Part1):2016.Althoughbasesheardecreased withincreasingirregularityduetolongertimeperiods,this reduction was accompanied by higher deformation demands, making such configurations structurally less efficient.
Torsional irregularity was found to be most significant in irregular plans due to eccentricity between the center of
massandrigidity,leadingtounevenforcedistributionand increased vulnerability. Overall, the study confirms that increasing plan irregularity negatively impacts seismic performance. Therefore, regular configurations are preferable in seismic regions, while irregular buildings requirecarefuldesignconsiderationstoensuresafetyand stability.
6. FUTURE SCOPE OF RESEARCH
Thepresentstudyislimitedtolineardynamicanalysisusing theresponsespectrummethod;therefore,futureresearch can focus on nonlinear time-history analysis to capture realisticinelasticbehaviorunderstronggroundmotion.The inclusion of soil–structure interaction effects can further improve the accuracy of seismic response prediction. Additionally,theperformanceofirregularbuildingscanbe enhanced by incorporating lateral load-resisting elements such as shear walls, bracings, or base isolation systems, which should be explored in future studies. Experimental validationofanalyticalresultsusingscaledmodelsorshake tabletestingcanalsoprovidevaluableinsights.Moreover, extending the study to different seismic zones and considering variations in building height and material propertieswouldhelpindeveloping morecomprehensive designrecommendations.
REFERENCES
1. Chopra,A.K.,2017.DynamicsofStructures:Theoryand ApplicationstoEarthquakeEngineering.5thed.Boston: PearsonEducation.
2. Clough, R.W. and Penzien, J., 2003. Dynamics of Structures.3rded.Berkeley:ComputersandStructures Inc.
3. Kalkan,E.andKunnath,S.K.,2006.‘Effectsofvertical irregularityonseismicresponseofreinforcedconcrete buildings’,EngineeringStructures,28(6),pp.829–838.
4. Paulay,T.andPriestley,M.J.N.,1992.SeismicDesignof ReinforcedConcreteandMasonryBuildings.NewYork: JohnWiley&Sons.
5. Sapkota, B., Bhandari, M. and Shrestha, S., 2022. ‘Seismic performance evaluation of irregular RC buildings using ETABS’, International Journal of Civil EngineeringandTechnology,13(4),pp.45–58.
6. Bureau of Indian Standards, 2016. IS 1893 (Part 1): 2016 – Criteria for Earthquake Resistant Design of Structures.NewDelhi:BIS.
7. Raj,K.G.,Roopanjali,S.andAkshatha,P.,2025.‘Impact of irregularities on seismic fragility of reinforced concretestructures’,DiscoverCivilEngineering,2(101), pp.1–15.
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 05 | May 2026 www.irjet.net p-ISSN: 2395-0072
8. Kumar,P.andSingh,A.,2022.‘Comparativestudyon seismicanalysisofregularandplanirregularbuildings’, MaterialsToday:Proceedings,71(2),pp.325–331.
9. Barman, P., 2019. ‘Seismic analysis of plan irregular building: A comparative study’, Journal of Emerging TechnologiesandInnovativeResearch,6(6),pp.650–660.
10. Sunitha,G.andLakshmi,P.,2025.‘Comparativestudy onasymmetricstructureswithdifferentinfillmaterials using ETABS’, International Journal of Scientific Research in Science, Engineering and Technology, 11(3),pp.210–218.
11. Khadka,S.,2025.‘SeismicbehaviourofasymmetricRC structures’, International Journal of Innovative ResearchinEngineeringandManagement,12(2),pp. 45–53.
12. Miah,M.F.etal.,2025.‘Seismicperformanceevaluation of multi-storied RC buildings with varied plan configurations’,ResearchSquarePreprints,pp.1–18.
13. Sharma,V.andGupta,R.,2023.‘SeismicresponseofRC framed irregular structures’, Materials Today: Proceedings,93(3),pp.530–537.
14. Ladiya, Y., Chourasia, M. and Satbhaiya, R., 2026. ‘Review on analysis of RCC irregular and setback buildingunderdynamicloadingusingETABS’,IJRASET, 14(3),pp.1–10.
15. Joseph, P. and Kuruvilla, R., 2021. ‘Effects of irregularities on seismic response of high-rise structures in ETABS’, International Journal of EngineeringResearch&Technology,9(9),pp.1–6.
16. Krishnendu,M.S.andSreelekshmi,S.,2026.‘Evaluation of structural irregularities in H-shaped RC buildings’, IJERT,15(3),pp.1–8.
17. Hari,A.S.andRani,B.P.,2025.‘Seismicperformanceof RC framed structures with setback irregularity’, IJRASET,13(5),pp.1–9.
18. Varadharajan, S., Sehgal, V.K. and Saini, B., 2014. ‘SeismicresponseofmultistoreyRCbuildingswithplan irregularity’,KSCEJournalofCivilEngineering,18(7), pp.2096–2103.
19. Tena-Colunga,A.,2004.‘Evaluationofcodeprovisions forirregularstructures’,EarthquakeSpectra,20(3),pp. 939–962.
20. Akkar,S.andGülkan,P.,2002.‘Acomparativestudyof RC building irregularities’, Engineering Structures, 24(2),pp.155–165.
21. Moehle, J.P., 2015. Seismic Design of Reinforced ConcreteBuildings.NewYork:McGraw-Hill.
22. Fardis, M.N., 2009. Seismic Design, Assessment and RetrofittingofConcreteBuildings.Springer.
23. Ghobarah, A., 2001. ‘Performance-based design in earthquakeengineering’,EngineeringStructures,23(8), pp.878–884.
24. Paulay, T., 2001. ‘Concepts of ductility in seismic design’, Bulletin of the New Zealand Society for EarthquakeEngineering,34(3),pp.133–144.
25. Goel,R.K.andChopra,A.K.,1997.‘Periodformulasfor moment-resisting frame buildings’, Journal of Structural Engineering (ASCE), 123(11), pp. 1454–1461.
26. Krawinkler, H. and Seneviratna, G.D.P.K., 1998. ‘Pros andconsofpushoveranalysis’,EngineeringStructures, 20(4–6),pp.452–464.
27. Chopra, A.K. and Goel, R.K., 2002. ‘A modal pushover analysis procedure’, Earthquake Engineering & StructuralDynamics,31(3),pp.561–582.
28. FEMA356,2000.PrestandardandCommentaryforthe SeismicRehabilitationofBuildings.FederalEmergency ManagementAgency.
29. IS456,2000.PlainandReinforcedConcrete–Codeof Practice.BureauofIndianStandards.
30. Computers and Structures Inc., 2022. ETABS User Manual.Berkeley,California.
31. ASCE7-16,2016.MinimumDesignLoadsforBuildings and Other Structures. American Society of Civil Engineers.
