International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 04 | Apr 2026 www.irjet.net p-ISSN: 2395-0072
PERFORMANCE EVALUATION OF PHASE CHANGE MECHANISM (PCM)
BALL – INTEGRATED CONCRETE: STRENGTH AND THERMALREGULATION
RAHUL YADAV, RAJ CHITRA AMIT, RUDRA PRATAP SINGH, SHASHANK
Department of Civil Engineering, Babu Banarasi Das Institute of Technology & Management, Lucknow, India
Abstract - The construction industry consumes a large amount ofenergy, especiallyfor heatingandcoolingbuildings, which contributes to greenhouse gas emissions. To improve energy efficiency, this study explores the use of Phase Change Materials (PCMs) in concrete. PCMs can absorb heat when temperatures rise and release it when temperatures drop, helping to maintain stable indoor conditions. In this research, paraffin wax is used as the PCM and is enclosed inside small spherical balls to prevent leakage, then embedded into concrete cubes. Each cube contains twoPCMballsandistested for compressive strength, ultrasonic pulse velocity (UPV), and thermal performance, with results compared to normal concrete. The findings show that adding PCM balls slightly reduces the concrete’s strength due to weaker bonding and small voids, but the strength still remains within acceptable limits. At the same time, the thermal performance improves significantly, as the PCM helps delay temperature rise and retainheat for longer periods. Thismeansbuildingsmadewith such concrete could require less energy for heating and cooling. Overall, although there is a small reduction in strength, the improvedthermalefficiencyanddurabilitymake PCM-integrated concrete a promising and sustainable construction material.
Key Words: Phase Change Materials (PCM), PCM concrete, paraffin wax, thermal energy storage, sustainableconstruction,energyefficiency,compressive strength, ultrasonic pulse velocity (UPV), thermal regulation, encapsulation technique
1. INTRODUCTION
This section introduces the study. Modern construction requires both structural safety and energy efficiency, as a large portion of building energy is used for heating and cooling. Therefore, materials that can regulate indoor temperature are increasingly important. Phase Change Materials (PCMs) are effective for thermal energy storage because they absorb and release heat within a narrow temperaturerange,helpingmaintainstableconditions. Concrete iswidelyused due toits strengthand durability, but it has poor thermal performance, leading to higher energyconsumption.Toimprovethis,PCMssuchasparaffin wax can be incorporated into concrete. However, direct
mixingmaycauseleakage,reducedstrength,anddurability issues.
To address these challenges, this study uses a macroencapsulationmethod,wherePCMisenclosedinspherical balls and embedded into concrete. This approach reduces leakageandlimitstheimpactonmechanicalproperties.The study aims to evaluate compressive strength and thermal performance of PCM-integrated concrete, highlighting its potentialforenergy-efficientandsustainableconstruction.
1. LITERATURE REVIEW
ResearchonPhaseChangeMaterials(PCM)inconcrete shows a clear balance between improved thermal performance and reduced mechanical strength. Studies consistently report that PCM enhances thermal energy storage by absorbing and releasing heat, helping regulate temperatureinbuildings.However,thisbenefitoftencomes with drawbacks such as reduced compressive strength, increasedporosity,andpotentialdurabilityconcernsdueto weakbondingbetweenPCMandthecementmatrix.
A 2022 review highlighted that PCM improves thermal storageregardlessoftheincorporationmethod,butstrength lossremainsakeychallenge.Macro-encapsulation,especially non-contact methods, is considered more effective as it minimizes direct interaction between PCM and concrete, preservingstructuralintegrity.Onenotableapproachisthe useofhollowsteelballsfilledwithPCM,whichofferbetter containment and thermal conductivity. Dong et al. demonstrated that such systems provide high latent heat capacity(around200.5J/g)withminimalleakageevenafter repeatedthermalcycles.TheirresultsalsoshowedthatPCMintegratedconcretecanreduceindoorpeaktemperaturesby 25–33%anddelayheattransfer.
Despitetheseadvantages,increasingPCMcontentleadsto areductionincompressivestrength.Forexample,strength decreasedprogressivelywithhigherPCMreplacementlevels, mainlyduetoweakbondingbetweensmoothPCMsurfaces andthecementmatrix.However,eventheloweststrength values remained within acceptable structural limits, indicatingpracticalusability.
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 04 | Apr 2026 www.irjet.net p-ISSN: 2395-0072
Several other studies support these findings. Adesina (2020) and Sharma et al. (2022) emphasized improved thermal efficiency and reduced energy demand but noted strengthanddurabilityconcerns.Zhangetal.(2013)andWei et al. (2017) highlighted the importance of proper encapsulation to prevent leakage and improve durability. Sakulich et al. (2012) and Memon et al. (2015) reported betterthermalregulationbutreducedstrengthduetolower density and weak bonding. Pilehvar et al. (2017) found microencapsulationeffectivebutcostly,whileFenoLleraetal. (2013)observedreducedworkabilityinfreshconcrete.More
recentworkbyWangetal.(2026)suggeststhataddingfibres canhelprecoversomestrength,thoughitincreasessystem complexity.
Overall, these studies confirm that PCM-integrated concrete offers significant thermal benefits and energy savings, but careful design is required to balance thermal performancewithstructuralstrength.
Table 1: Summary of Literature Review on PCM Integrated Concrete
S. No. Researcher(s) Focus Area Key Findings Research Gap
1 Adesina(2020) ReviewofPCMin concrete Improvesthermalstorage butreducesstrength Lacks experimental validation
2 Sharma (2022) et al. PCMinsustainable buildings Reduces energy consumption Durabilityissues
3 Zhang (2013) et al. PCM in cement mortar Improvedthermalstorage Leakageissues
4 Sakulich (2012) et al. PCMincomposites Betterthermalregulation Reducedstrength
5 Pilehvar et al.(2017) Micro-encapsulated PCM Improvedstability Highcost
6 Weietal.(2017) Durabilitystudy Improveddurability Complexprocess
7 Memon et al. (2015) Macro-encapsulation Betterinsulation Lowerstrength
8 FenoLleraetal. (2013) PCMinSCC Improvedinertia Reducedworkability
9 Wangetal.(2026) FiberPCMconcrete Improvedstrength Complexdesign
Volume: 13 Issue: 04 | Apr 2026 www.irjet.net p-ISSN: 2395-0072
2. METHODOLOGY
The study follows an experimental approach including material selection, PCM encapsulation, concrete casting, curing,andtesting.ParaffinoctadecaneisusedasthePhase Change Material (PCM) because it is suitable for building temperatureregulation.ThePCMisfilledintohollowsteel ballsusingavacuumprocessandthensealedwithepoxyto preventleakage.ThesePCM-filledballsareusedaspartial replacementofcoarseaggregateinconcrete.
Concrete mixes are prepared with different replacement levelsofPCMballs(0%,25%,50%,75%,and100%)using M25 grade concrete. A constant water–cement ratio is maintained, and a superplasticizer is added to improve workability. The PCM balls are added at the final stage of mixingtoavoiddamage.Concretecubesofsize150mm× 150mm×150mmarecast,eachcontainingtwoPCMballs placedevenly.
The specimens are cured in water for 7, 14, and 28 days. Tests conducted include compressive strength, ultrasonic pulse velocity (UPV), and thermal performance using infraredtemperaturemeasurements.Thesetestsareusedto evaluate both the strength and thermal behavior of PCMintegrated concrete for possible use in energy-efficient buildings.
3. System Architecture of Ball-Integrated Concrete
Thesystemofball-integratedphasechangeconcreteworks in four main steps: PCM selection, concrete preparation, thermalregulation,andstrengthchecking.
First,asuitablePhaseChangeMaterial(PCM)isselectedand filledintohollowsteelballs.Theseballspreventleakageand helptransferheatefficiently.
Second, the PCM-filled balls are added into concrete by partially replacing coarse aggregate. During high temperature, the PCM absorbs heat and melts, reducing temperaturerise.Whentemperaturedrops,itsolidifiesand releasesheat,helpingmaintainstabletemperature.
Third, the system improves thermal performance by reducingtemperaturepeaksandfluctuations,whichhelpsin energysavingsforbuildings.
Finally,the strengthof concreteis tested. Sincesteel balls reduce bonding with cement, compressive strength decreasesasmorePCMballsareadded.Therefore,aproper balanceisneededbetweenstrengthandthermalbenefits.
Overall,thissystemimprovesthermalcomfortandenergy efficiencywhilemaintainingusablestructuralstrength.
4. Results and Evaluation
The results of this study show that ball-integrated Phase Change Material (PCM) concrete significantly improves thermalperformance.TheinclusionofPCM-filledsteelballs helpsinreducingindoortemperatureanddelayingthepeak heat time compared to conventional concrete. In experimental studies, the peak indoor temperature was observedtodropconsiderablywhenPCMpanelswereused, confirming that the latent heat storage capacity of PCM effectively absorbs excess heat during high-temperature conditions and releases it slowly when the temperature decreases.Thisprocesshelpsinmaintainingamorestable andcomfortableindoorenvironment.
The thermal performance improvesas the amount of PCM ballsintheconcreteincreases.ThisisbecauseahigherPCM contentallowsmoreheatenergytobestoredandreleased during phase change, which reduces sudden temperature fluctuations.Asaresult,PCM-integratedconcretecanreduce the dependence on artificial cooling systems and improve overallenergyefficiencyinbuildings.
However, the mechanical performance shows a declining trendwithincreasingPCMcontent.Thecompressivestrength ofconcretedecreasesasmorePCMballsreplacethenatural coarseaggregate.Thisreductioninstrengthismainlydueto theweakbondingbetweenthesmoothsteelsurfaceofthe PCMballsandthecementmatrix,whichcreatesinterfacial gaps and reduces load-bearing capacity. Despite this reduction, lower and moderate replacement levels still maintainacceptablestructuralstrength.
Overall, the results clearly indicate a trade-off between thermal efficiency and mechanical strength. While higher PCMcontentimprovestemperatureregulation,itnegatively affectsstrength.Therefore,anoptimizedreplacementlevelis necessary to achieve a balance between both properties. ModerateuseofPCMballsprovidesthebestperformanceby offering significant thermal benefits while maintaining sufficientstructuralintegrity.
CONCLUSIONS
This study concludes that ball-integrated Phase Change Material (PCM) concrete is an effective solution for improving thermal performance in buildings while maintainingacceptablestructuralstrength.TheuseofPCMfilled steel balls helps control indoor temperature by absorbing heat during high temperatures and releasing it during cooling periods, which reduces peak temperatures andimprovesthermalcomfort.
Resultsshowthatthermalefficiencyincreaseswithhigher PCMcontent.However,compressivestrengthdecreasesdue to weak bonding between the steel balls and the cement matrix. Despite this reduction, the concrete still performs
International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 13 Issue: 04 | Apr 2026 www.irjet.net p-ISSN: 2395-0072
adequately for non-structural and semi-structural applications.
A balanced replacement level of about 25–50% coarse aggregatewithPCMballsisfoundtobeoptimal,providinga goodcompromisebetweenstrengthandthermalbenefits. Overall,thismaterialshowsstrongpotentialforsustainable construction,especiallyinbuildingelementslikewallsand panels where thermal regulation is important. It helps reduceenergyconsumption andsupportsenergy-efficient buildingdesign.
ACKNOWLEDGEMENT
Theauthorexpressesprofoundgratitudetothefaculty members of the Department of Civil Engineering, particularly the project guide, for their invaluable technical guidance, constructive feedback, and unwaveringsupportthroughouttheconceptualization anddocumentationofthisresearch.Specialappreciation is extended to the Structural Engineering Laboratory staff for their assistance in concrete casting, curing, compressive strength testing, and non-destructive evaluationusingUltrasonicPulseVelocityandrebound hammer equipment. The Material Testing Laboratory teamprovidedcriticalsupportforthermalperformance characterizationandPCMstabilitytesting.
Sincere thanks to fellow B.Tech Civil Engineering batchmatesfortheircollaborationduringexperimental work, data collection, and constructive peer review sessions that strengthened the technical rigor of this study.Theauthoracknowledgeswithappreciationthe seminal contributions of global researchers in PCM concretetechnology,particularlythepioneering work onhollowsteelballmacro-encapsulationthatformsthe technicalfoundationofthisinvestigation.Institutional computingresourcesprovidedbytheCivilEngineering Departmentfacilitatedliteraturereview,dataanalysis, andmanuscriptpreparation.Thisresearchreceivedno externalfundingandwasconductedusingdepartmental research facilities as part of the regular B.Tech curriculum.
Finally, heartfelt thanks to family members for their continuous encouragement andunderstandingduring extendedlaboratoryhoursanddocumentationphasesof thisprojectwork.Appreciationisalsoextendedtothe researchers whose published work on PCM concrete, macro-encapsulation, and thermal energy storage formedthetechnicalbasisforthispaper.
REFERENCES
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