Experimental Investigations On Strength Characteristics Of .
International Journal of Trend in Scientific Research and Development (IJTSRD)International Open Access Journal www.ijtsrd.comISSN No: 2456 - 6470 Volume - 2 Issue – 6 Sep – Oct 2018Experimental Investigations on Strength Characteristics of HighPerformance Concrete Using Silica Fume and SuperplasticizerDr. K. Perumal1, S. Senthilkumar2, K. Sekar31Head of Department, 2Lecturer (Senior Grade), 3Associate Professor,1,2Dept of Civil Engineering, Sri Ramakrishna Mission Vidyalaya Polytechnic College, Tamil Nadu, India3Dept of Civil Engineering, Ranganathan Engineering College, Coimbatore, Tamil Nadu, IndiaABSTRACTFor several decades, concrete has been the mostwidely used construction material. Thoughconventional concrete (CC) performs very well undernormal conditions, in special situations a very highcompressive strength of concrete is necessary togetherwith sustainability to aggressive environments.Hence, higher compressive strength of range 60-140MPa is essential. The concrete mixes so far weredesigned only for strength and workabilityrequirements. For the performance of longsatisfactory life, the designed mixes should bechecked and proved for their durability propertiessuch as low permeability, high corrosion resistance,freezing and thawing resistance, fire existence etc.This necessitates a detailed study on Highperformance concrete (HPC). This paper formulates asimplified mix design procedure for HPC bycombining BIS and ACI code methods of mix designand available literatures on HPC. Based on the aboveprocedure M80 and M100 mixes are arrived at. TheseHPC mixes are tested experimentally forcompression, split tension, flexure and workability.The performance of the designed mixes is very goodand the results are reported in this paper.Keyword: low permeability, resistance, fire existence,HPCI.INTRODUCTIONHPC is a construction material which is being used inincreasing volumes in recent years due to its longterm performance and better rheological, mechanicaland durability properties than CC. HPC possessesinvariably high strength, reasonable workability andnegligible permeability. Compared to CC, preparationof HPC requires lower water-binder (w/b) ratio andhigher cement content. The durability properties ofconcrete are given importance, which makes HighStrength Concrete (HSC) into HPC. HSC refers toconcretes of grade above M60. High strength andbetter durability properties become reality for CC byreducing porosity, in homogeneity, micro cracks inconcrete and the transition zone. This is how HPC isevolved.Incorporation of mineral admixtures like Silica Fume(SF), Fly ash, Granulated ground blast furnace slag,Rice husk ash act as pozzolanic materials as well asmicro fillers, thereby the microstructure of hardenedconcrete becomes denser and improves the strengthand durability properties. Addition of chemicaladmixtures such as super plasticizer improves theproperties of plastic concrete with regard toworkability, segregation etc.The HPC permits use of reduced sizes of structuralmembers, increased building height in congestedareas and early removal of formwork. The use of HPCin pre-stressed concrete construction makes greaterspan-depth ratio, early transfer of pre-stress and earlyapplication of service loads. Low permeabilitycharacteristic of HP Creduces risk of corrosion ofsteel and attack of aggressive chemicals. This permitsthe use of HPC in marine/offshore structures, nuclearpower plants, bridges and places of extreme andadverse climatic conditions. Eventually, HPC reducesmaintenance and repair costs.II.MECHANISM OF HPCAccording to Nevillie “HPC is a concrete to fulfillspecified purpose and no special mystery about it, nounusual ingredients or special equipment’s have to be@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 382
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470used. But to understand the behavior of concrete andwill, to produce a concrete mix within closelycontrolled tolerances”. Concrete is a three-phasecomposite material, the first two phases beingaggregates and bulk hydrated cement paste (hcp) andthe third being the “transition zone”. The transitionzone is the interfacial region between the aggregateparticles and the bulk “hcp”. It is the weakest link andif this is strengthened, then the strength andimpermeability (durability characteristics) of concreteare improved to a greater extent. This is madepossible by reducing w/b ratio and use of SF. SFimproves the above properties by pozzolanic actionand by reactive filler effect. SF contains a very highpercentage of amorphous silicon dioxide which reactswith large quantity of Ca(OH)2 produced duringhydration of cement to form calcium-silicate-hydrate(C-S-H) gel. This gives strength as well as improvesimpermeability. This is known as pozzolanic action(chemical mechanism). Another action, a physicalmechanism called “filler effect” in which the smallspherical shaped SF particles disperse in the presenceof a super plasticizer to fill the voids between cementparticles and accelerates the hydration of C3S, sinceSF is fine reactive filler. These results in well packedconcrete mix. Due to pozzolanic action between SFand Ca (OH) 2, the larger size crystals of CA(OH)2converts to crystal of C-S-H gel which is dense,leading to reduction of pore size. This effect alongwith the improved particle distribution results inreduction of the thickness of transition zone and leadsto densely packed stronger and less permeableconcrete.III.SIGNIFICANCE AND OBJECTIVESThe objectives of the present investigation are todevelop a simplified mix design procedure, speciallyfor HPC by varying the percentage replacement ofcement by SF (0-15%) at a constant dosage of superplasticizer, based on BIS & ACI code methods of mixdesign procedure and available literatures on HPC.Investigations were carried out on the aboveprocedure to produce HPC mixes for M80 and M100grades using 12.5mm maximum size of aggregates toascertain the workability and the mechanicalproperties of the designed mixes and to find anoptimum cement replacement by SF.Hence in the present investigation more emphasis isgiven to study the HPC using SF and super plasticizerso as to achieve better concrete composite and also toencourage the increased use of SF to maintainecology.IV.EXPERIMENTAL PROGRAMMEExperimental investigations have been carried out onthe HPC specimens to ascertain the workability andstrength related properties such as compressivestrength, split tensile strength, flexural strength andElastic modulus of the designed trial mixes and alsoNon- Destructive Test (NDT) – Ultrasonic PulseVelocity (UPV) has been carried out to check thequality of concrete.4.1 Materials used1. Ordinary Portland Cement (OPC), 53 Gradeconforming to BIS: 12269 – 1987.2. Silica Fume as mineral admixture in dry densifiedform obtained from ELKEM INDIA (P) LTD.,Mumbai conforming to ASTM C – 1240.3. Super plasticizer (chemical admixture) based onSulphonatedNaphthaleneFormaldehydecondensate – CONPLAST SP 430 conforming toBIS: 9103 – 1999 and ASTM C-494.4. Locally available quarried and crushed granitestones confirming to graded aggregate of nominalsize 12.5 mm as per table 2 of BIS: 383 – 1970with specific gravity 2.82 and fineness modulus6.73 as Coarse aggregates (CA).5. 5. Locally available Karur river sand conformingto Grading zone II of table 4 of BIS: 383-1970with specific gravity 2.60 and fineness modulus2.96 as fine aggregates (FA).6. Water: Drinking water supplied to Coimbatorecity from Siruvani dam for concreting and curing.4.2 Mix Design for HPCSince there is no specific method of mix design foundsuitable for HPC, a simplified mix design procedure isformulated by combining the BIS method, ACImethods for concrete mix design and the availableliteratures on HPC using SF.FormulationofmixdesignprocedureTarget mean strengthThe target mean strength ( fck ) is calculated asfollows:(fck ) fck (t x S) with usual BIS notations. Whenadequate data are not available to establish S’, the (fck ) value can be determined from the following table1 as given by ACI Report 318.@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 383
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470Table 1: Target mean strength when data are notavailable to establish a standard deviationSpecified characteristicTarget meancompressive strength,compressive strength,fck (MPa)fck (MPa)Less than 20.5fck 6.920.5 - 34.5fck 8.3More than 34.5fck 9.7Selection of maximum size of coarse aggregate(CA)The maximum size of the coarse aggregate is selectedfrom the following table 2 as given by ACI Report211.4R.93.Table 2: Maximum size of coarse aggregateRequired ConcreteMaximum aggregateStrength (MPa)size (mm)Less than 6220 - 25Greater than or equal to10 – 12.562Estimation of free water contentThe water content to obtain the desired workabilitydepends upon the amount of water and amount ofsuper plasticizer and its characteristics. However, thesaturation point of the super plasticizer is known, andthen the water dosage is obtained from the followingtable 3. If the saturation point is not known, it issuggested that a water content of 145 litres/m3 shallbe taken to start with.Table 3: Determination of the minimum )be taken as 1.5% or less since it is HPC, and thenadjusting it on the basis of the result obtained with thetrial mix.Table 4 Approximate entrapped air contentNominal maximumEntrapped air, assize of coarsepercent of volume ofaggregate (mm)concrete102.512.52.0201.5251.0Selection of coarse aggregate (CA) contentThe coarse aggregate content is obtained from thefollowing table 5 as a function of the typical particleshape. If there is any doubt about the shape of the CAor if its shape is not known, it is suggested that a CAcontent of 1000 kg/m3 of concrete shall be taken tostart with. The CA so selected should satisfy therequirements of grading and other requirements ofBIS: 383 – 1970.Table 5 Coarse aggregate contentSelection of water - binder (w/b) ratioThe water-binder ratio for the target meancompressive strength is chosen from figure 1, theproposed w/b ratio Vs compressive strengthrelationship. The w/b ratio so chosen is checkedagainst the limiting w/c ratio for the requirements ofdurability as per table 5 of BIS: 456 – 2000, and thelower of the two values is adopted.Super plasticizer dosageThe super plasticizer dosage is obtained from thedosage at the saturation point. If the saturation point isnot known, it is suggested that a trial dosage of 1.0%shall be taken to start with.Estimation of air contentThe air content (approximate amount of entrapped air)to be expected in HPC is obtained from the followingtable 4 as given by ACI Report 211.4R.93 for themaximum size of CA used. However, it is suggestedthat an initial estimate of entrapped air content shallFig.1 Proposed w/b ratio Vs compressive strengthrelationship Calculation of binder contents@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 384
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470The binder or cementitious contents per m3 ofconcrete is calculated from the w/b ratio and thequantity of water content per m3 of concrete.Assuming the percentage replacement of cement bySF (0-15%), the SF content is obtained from the totalbinder contents. The remaining binder content iscomposed of cement. The cement content socalculated is checked against the minimum cementcontent for the requirements of durability as per table5 and 6 of BIS: 456 – 2000 and the greater of the twovalues is adopted.Super plasticizer content:The mass of solids in the super plasticizer (Msol) inkg, the volume of liquidsuper plasticizer (Vliq), thevolume of water in the liquid super plasticizer (Vw)and the volume of solids in the liquid super plasticizer(Vsol) are calculated from the following equations:dM sol C 100M 100Vliq sols SsVwVsol 100 s Vliq Ss 100 Vliq VwWhereC mass of the cementitious materials (kg)d super plasticizer dosage expressed as the % of itssolid contents total solid content of the super plasticizer inpercent, andSs specific gravity of the liquid super plasticizerEstimation of fine aggregate (FA) contentThe absolute volume of FA is obtained from thefollowing equation: MMMVfa 1000 Vw c sf ca Vsol Vea ScSsfSca WhereVfa absolute volume of FA in litres per m3 ofconcreteVw volume of water (litres) per m3 of concreteMc mass of cement (kg) per m3 of concreteSc specific gravity of cementMsf, Mca total masses of the SF and CA (kg) per m3of concrete respectivelySca, Ssf specific gravities of saturated surface drycoarse aggregate and silica fume respectively, andVsol, Vea volume of solids in the super plasticizerand entrapped air (litres) per m3 of concreterespectively.The fine aggregate content per unit volume ofconcrete is obtained by multiplying the absolutevolume of fine aggregate and the specific gravity ofthe fine aggregate.Moisture adjustmentsThe actual quantities of CA, FA and water content arecalculated after allowing necessary corrections forwater absorption and free (surface) moisture contentof aggregates. The volume of water included in theliquid super plasticizer is calculated and subtractedfrom the initial mixing water.Unit mass of concreteThe mass of concrete per unit volume is calculated byadding the masses of the concrete ingredients.Trail mix proportionBecause of many assumptions underlying theforegoing theoretical calculations, the trial mixproportions must be checked. If necessary, the mixproportion should be modified to meet the desiredworkability and strength criteria, by adjusting thepercentage replacement of cement by SF, percentagedosage of super plasticizer solid content of binder, aircontent and unit weight by means of laboratory trialbatches to optimize the mix proportion. Freshconcrete should be tested for workability, unit weightand air content. Specimens of hardened concreteshould be tested at the specified age.4.3Mixture proportions and casting ofspecimens:Mix proportions are arrived for M80 and M100 gradesof concrete based on the above formulated mix designprocedure by replacing 0, 2.5, 5, 7.5, 10, 12.5 & 15percent of the mass of cement by SF & the materialrequirements per m3 of concrete are given in table 6and 7. The ingredients for various mixes are weighedand mixing was carried out using a drum type mixerand casting were done in steel moulds for concretecubes 150 mm size, cylinders 150 mm x 300 mm andbeams 100 mm x 100 mm x 500 mm. Curing wasdone under water for various desired periods.@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 385
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470Table 6 Details of HPC trial mixes for M80 gradeSFw/b Cement SFFACA Super plastiMix designation(%) ratio(Kg)(Kg) (Kg) (Kg)cizer (lit)C100.285 509.000764.04 107012.52C22.5 0.285 496.28 12.73 759.50 107012.52C350.285 483.55 25.45 755.00 107012.52C47.5 0.285 470.83 38.18 750.44 107012.52C510 0.285 458.10 50.90 745.88 107012.52C612.5 0.285 445.38 63.63 741.34 107012.52C715 0.285 432.65 76.35 736.82 107012.52Table 7 Details of HPC trial mixes for M100 gradeSF w/b Cement SFFA CA Super plastiMix designation(%) ratio(Kg)(Kg) (Kg) (Kg)cizer (lit)C1100.25580.00705 107014.26C122.5 0.25565.514.5 700 107014.26C1350.25551.029.0 694 107014.26C147.5 0.25536.543.5 689 107014.26C1510 0.25522.058.0 684 107014.26C1612.5 0.25507.572.5 679 107014.26C1715 0.25493.087.0 674 107014.26V.TESTS ON FRESH AND HARDENEDCONCRETEWorkability tests such as Slump test, CompactionFactor test and Vee-Bee consistometer test werecarried out for fresh concrete as per BISspecifications, keeping the dosage of super plasticizeras constant at 3 % by weight of binder. For hardenedconcrete, cube compression strength test on 150 mmsize cubes at the age of 1 day, 3 days,7 days, 14 days,28 days & 56 days of curing were carried out using3000 KN capacity compression testing machine as perBIS : 516-1959. Also compression strength and splittensile strength tests on 150 mm x 300 mm cylindersand flexure test on 100 mm x 100 mm x 500 mmbeams were carried out on 28 days cured specimensas per BIS specifications. The stress – strain graph forHPC is obtained using compressor meter fitted tocylinders during cylinder compressive strength test.UPV measurements were taken using NDT method on150 mm size cubes for assessing the quality ofconcrete as per BIS : 13311 (Part 1) – 1992.VI.RESULTS AND DISCUSSIONTests on fresh concreteThe test results of workability are listed in table 8 and9 and also shown in figures 2, 3 & 4. It was observedthat the workability of concrete decreased as thepercentage of SF content was 56139.56139.56Tests on hardened concreteThe results of cube compression strength, cylindercompression strength, spilt tensile strength, flexuralstrength and Modulus of Elasticity are also listed intable 8 and 9.The optimum percentage of cement replacement bySF is 10% for the above tests for M80 and M100grades of concrete. This may be due to the fact thatthe increase of strength characteristics in concrete isdue to the pozzolanic reaction and filler effects of SF.The variations of average compressive strengths withrespect to % of SF at different ages are shown infigures 5&6. The ratio of cylinder to cubecompression strength was found to be 0.81. Theflexure strengths obtained experimentally are higherthan the value calculated by the expression 0.7 fck asper BIS: 456-2000. The variation of Modulus ofElasticity values with respect to % of SF at 28 daysfor M80 & M100 grades of concrete are shown infigure 7. The stress – strain curve at 28 days for M80grade of concrete is shown in figure 8, for 10% SFcontent which is found to be optimum for Modulus ofElasticity values also. The Modulus of Elasticityachieved was 3.97 GPa and 4.15 GPa for M80 M100grades of concrete respectively at age of 28 dayscuring. The values are comparatively lower than thevalues calculated by the expression 5000 fck as per@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 386
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470BIS: 456-2000. The UPV results of NDT are shown intable 10. The velocities prove that the quality ofconcrete is excellent.Table 8 Properties of HPC mixes for M80 gradePROPERTIESC1C2C3C4Silica Fume (%)02.557.5C5C6C71012.515Cube compressive strength (MPa),1day24.00 29.78 32.44 33.3335.5634.99 34.103days39.11 44.44 44.89 50.2255.1149.48 48.897days52.44 59.23 65.33 66.2269.4865.34 62.3714days59.26 65.63 67.56 72.0078.6774.37 73.3328days67.11 75.56 76.44 83.1190.2285.04 82.2256days75.32 84.65 86.30 94.22 101.33 95.44 92.11Cylinder compressive strength (MPa), 28days 52.97 59.98 61.00 66.0471.8765.53 65.08Split tensile strength (Mpa), 28 days4.955.165.315.665.945.385.31Flexural strength (Mpa), 28 daysElastic modulus(Gpa), 28daysSlump .737.736.752464541372215Compaction Factor0.950.930.920.880.850.800.79Vee-Bee degrees (secs)13141517182735C15C16C177.51012.515Table 9 Properties of HPC mixes for M100 gradePropertiesC11 C12 C13C14Silica Fume (%)02.55Cube compressive strength (MPa),1day28.59 34.37 36.0039.4144.7444.5941.193days45.78 52.74 52.8959.5667.1162.0760.897days62.37 68.74 73.6380.1584.7580.1578.0714days71.41 76.88 80.8885.0497.1993.3392.0028days83.11 89.04 93.89 100.80 110.66 105.33 102.6756days91.68 98.40 103.2 110.75 122.10 114.23 111.75Cylinder compressive strength (MPa), 28days 65.64 69.43 74.92Split tensile strength5.81 6.41 6.89(MPa), 28daysFlexural strength8.60 9.00 9.40(MPa), 28daysElastic modulus38.0 39.0 39.5(GPa), 28daysSlump 10.409.809.4041.441.540.840.925251815Compaction Factor0.860.850.830.820.810.780.75Vee-Bee degrees (secs)15171818205564@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 387
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2.515.0Table 10 Results of Ultrasonic pulse Velocity of cubes at 28daysDistancePulseTime taken to travel (t)Quality of concretetraveledvelocity(x10-6 525.335921.26ExcellentFigure 2 Workability through slump valuesFigure 5 Variation of average compressive strengthwith respect to % of SF at different ages (M80)Figure: 6 variation of mpa and the sfFigure 3 Workability through compaction factorvaluesFigure 4 Average compare strength of silica fumeFigure 8: variation of stress and strain@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 388
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470VII. CONCLUSIONSBased on the investigations carried out on HPCmixes, the following conclusions are drawn.1. A simplified mix design procedure for HPCusing SF and super plasticizer is formulated bycombining BIS & ACI code methods of mixdesign and available literatures on HPC.2. Theoptimumpercentageofcementreplacement by SF is 10% for achievingmaximum compressive, split tensile and flexuralstrengths and Elastic modulus.3. The 7 days to 28 days compressive strength ratioof HPC is 0.75 – 0.80.4. The BIS: 456-2000 code underestimates theflexural strength and over estimates the Modulusof Elasticity for HPC.5. Use of SF in concrete reduces the workability.6. The compression failure pattern of concrete is dueto crushing of coarse aggregate and not due tobond failure.VIII. ACKNOWLEDGEMENTThe authors also express their heartfelt thanks to theRamakrishna M Vidyalaya Management and the SRKVidyalaya Polytechnic College, Swamiji’s for havingfacilitated to present this paper. The author alsograteful to the faculty members for their kindsuggestions in bringing out this paper.IX.REFERENCES1. NEVILLE (2000), “Properties of concrete”,4th andfinal edition, Pearson Education Asia Pte. Ltd,England.2. METHA & MONTERIO (1999),“Concrete:microstructure, properties and materials”, Indianedition, Indian Concrete Institute, Chennai.3. NAWY (2001). “Fundamentals of highperformance concrete”, 2nd edition, John Wiley &Sons.Inc., New York.4. SHAH & AHMAD (1994), “High performanceconcretes and applications”, Edward Arnold,London.5. RIXOM & MAILVAGANAM (1996), “ChemicalAdmixtures for concrete”, 2nd edition, E & F. NSPON, London.6. JOSHI (2001), “Evolution of HPC mixescontaining silica fume,” The Indian ConcreteJournal, October 2001, Vol. 75, No.10, pp 627633.7. BASU (2001), “NPP Containment structures:Indian experience in silica fume-based HPC”, TheIndian Concrete Journal, October 2001, Vol.75,No10, pp656-664.8. AMIT MITTAL & BASU (1999), “Developmentof HPC for PC dome of NPP, Kaiga”, The IndianConcrete Journal, September 1999, Vol.73, No.9,pp548-556.9. AMIT MITTAL & KAMATH (1999), “Propertiesof HPC for PC dome of NPP, Kaiga”, The IndianConcrete Journal, September 1999, Vol.73, No.9,pp 561-568.10. CHINNAPPA (2001), “High PerformanceConcrete”, Proceedings of the advanced inconcrete technology with emphasis on HPC, heldat Pondicherry, pp 185-194.11. RAJAMANE (2000), “High PerformanceConcrete Mix Proportioning”, advanced course onHP materials and Methodologies for constructionand Rehabilitation of concrete structures, SERC,Chennai.12. JAGADISH(2001),“HighPerformanceconcrete”, proceedings of National seminar on”Waver of the Future, Civil Engineering in 21stcentury,” 15-16 June 2001, Association ofConsulting Civil Engineers (India), Bangalore, pp72-90.13. SHIGIHALLI & MANJUNATH (2002), HighStrength Concrete containing silica fume”,National Seminar on “Advances in concrete &concrete structures”, The Institution of Engineers(India), Belgaum.14. WANG & READ (1999), “Trials of grade 100high-strength concrete”, Magazine of ConcreteResearch, 51, No.6, Dec., pp 409-414.15. BASU (2001), “High Performance Concrete:Mechanism and Application”, ICI Journal, AprilJune 2001, pp15-26.16. IAN BURNETT (1991), “Silica Fume Concrete inMelbourne, Australia”, Concrete International,August 1991, pp 18-24.17. FRANCQIS DE LARRARD & THIERRYSEDRAN (2002), “Mixture – proportioning ofhigh performance concrete”, Cement and ConcreteResearch, 32 (2002), pp 1699-1704.@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 389
International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-647018. IS: 10262-1982, “Recommended guidelines forconcrete mix design”, Bureau of Indian Standards,New Delhi.25. IS: 383-1970, “Specification for coarse and fineaggregate from natural sources for concrete,Bureau of Indian Standards, New Delhi.19. SP: 23-1982, “Hand book on concrete mixes”,Bureau of Indian Standards, New Delhi.26. IS: 2386 (Part III) – 1963, “Methods of test foraggregates for concrete” Bureau of IndianStandards, New Delhi.20. IS 13311 (Part1): 1992, “Non-Destructive testingof concrete- Methods of Test”, Bureau of IndianStandards, New Delhi.21. IS: 516-1959, “Methods of tests for strength ofconcrete”, Bureau of Indian Standards, NewDelhi.22. IS: 9103:1999, “Concrete Admixtures –specification”, Bureau of Indian Standards, NewDelhi.23. IS: 5816-1970, “Method of test for splitting tensilestrength of concrete cylinders”, Bureau of IndianStandards, New Delhi.27. IS 12269: 1987, “Specification for 53 gradeordinary Portland cement”, Bureau of IndianStandards, New Delhi.28. IS 456:2000, “Plain and Reinforced Concrete –Code of practice”, 4th Edition, Bureau of IndianStandards, New Delhi29. AITCIN (1998), “High – Performance concrete”,1st edition, E& FN SPON, London.30. KRISHNARAJU (1998), “Design of concretemixes”, 3rd edition, CBS Publishers &Distributors, New Delhi.24. IS: 1199-1959, “Methods of sampling andanalysis of concrete”, Bureau of Indian Standards,New Delhi.@ IJTSRD Available Online @ www.ijtsrd.com Volume – 2 Issue – 6 Sep-Oct 2018Page: 390
Silica Fume as mineral admixture in dry densified form obtained from ELKEM INDIA (P) LTD., Mumbai conforming to ASTM C – 1240. 3. Super plasticizer (chemical admixture) based on Sulphonated Naphthalene Formaldehyde .
Chapter 3 3.1 The Importance of Strength 3.2 Strength Level Required KINDS OF STRENGTH 3.3 Compressive Strength 3.4 Flexural Strength 3.5 Tensile Strength 3.6 Shear, Torsion and Combined Stresses 3.7 Relationship of Test Strength to the Structure MEASUREMENT OF STRENGTH 3.8 Job-Molded Specimens 3.9 Testing of Hardened Concrete FACTORS AFFECTING STRENGTH 3.10 General Comments
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