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Home , Fly ash, Metakaolin

National Conference on Recent Trends in Engineering & Technology

Effect of Activated Flyash in based Hemant Chauhan#” Smt. Bhavna K. Shah* * # PG student, Department of Structural Engg., B.V.M. Engg. Associate Professor. Department of Structural College, V.V. Nagar, Gujarat Engg., B.V.M. Engg. College, V.V.Nagar, Gujarat 2 [email protected] [email protected]

Abstract— Recent trend in engineering, especially in structure is to develop economical, eco environmental and durable II. MATERIALS concrete with decreasing or reducing the use of natural material A. Cement and increasing the use of industrial waste or by products from Ordinary (53 grade) confirming to BIS industries without affecting the higher strength of concrete. To 12269 -1987 was used. It’s chemical composition and physical achieve this higher strength, OPC as a cementitious material is properties are given in table -1. not sufficient, so in this paper industrial waste like activated (class F), Oxide and Metakaolin are used as TABLE I supplementary cementitious materials in various proportions. By COMPOSITION OF CEMENT, ACTIVATED FLYASH & METAKAOLIN using this mineral admixtures with OPC cement, different five types of cement were prepared and same were used to find Chemical %age by mass compressive strength of concrete cubes at 3,7,14,28 and 56 days. Composition Cement Fly ash Metakaolin SiO2 20.1 48.53 51.6 Keywords— Compressive strength, Activated Flyash, Metakaolin, Al O 4.51 24.61 41.3 Iron Oxide, Workability 2 3 Fe2O3 2.5 7.59 0.64 CaO 61.3 9.48 0.52 MgO 1 2.28 0.16 I. INTRODUCTION Loss on 2.41 0.93 0.72 Concrete has played important role in infrastructure ignition development. Concrete has many advantages over other construction material including low cost, applicability under many conditions, adaptability, use and production of cement B. Flyash and concrete has increasingly become a major causes of global Fly Ash comprises of the non- combustible mineral portion ecological problems with special reference to the over of . Fly ash particles are glassy spherical shaped. It’s exploitation of non- renewable natural resources due to high- particles are finer than cement particles and have ball bearing temperature production processes, fossil fuels combustion and effect which helps to reduce amount of and improves extraction of raw material. Concrete is made up of cement, workability of concrete. The chemical compositions of fly ash coarse , fine aggregate and water. When water is are given in table 1. And physical properties are given in table added in to cement, chemical reaction takes place and due to 2. this hydration is generated. Out of that 25% of lime remains intact on surface and overtime it would be susceptible C. Metakaolin to the effect of weathering and loss of strength and durability. It is highly pozzolanic material. It is obtained by To overcome this effect, pozzolanic material i.e. siliceous calcinations of Algerian kaolin at 700˚ C for 7 hours. The silica material that develops any hydraulic cementitious properties in and alumina contained in the metakaolin are active and react the presence of lime is added into OPC cement which reacts with free lime to form C-S-H and alumina-silicates which with free lime and convert in to silicate hydrate (C-S- greatly improve the strength. H) which gives strength to concrete and also make it durable. D. Iron Oxide Activated Fly ash (type F) and Iron Oxide is industrial During the processing of steel in steel mills, iron oxide will waste and Metakaolin is easily available with low cost be formed on the surface of metal. This oxide is known as mill compared to used as a pozzolanic material to scale, occur during continuous , reheating and rolling replace OPC in concrete which reduces the amount of cement operation. This is used as replacement for the fine aggregate. used hence reducing the emission of CO2. All these materials are finer, particles are glassy which help E Aggregate in reducing amount of water and help to increase workability. Crushed stones of 20 mm down size were used as coarse By using this mineral admixture, cost of concrete is reduced aggregates and local river sand 1.18 mm down were used as and eco friendly concrete is developed. fine aggregate listed in table 3.

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat, National Conference on Recent Trends in Engineering & Technology

TABLE II PHYSICAL PROPERTY OF FLYASH TABLE V CONSTITUENT OF MATERIALS FOR DIFFERET CONCRETE MIX Property Experimental Value w/c Mix Mix Proportion / m3 ratio proportion 1 Fineness (passing 45μ IS: sieve) 78.9% 2 Specific Surface 4620 cm2/g 3 Unit weight 950 kg/m3 Cement Sand Coarse Water (kg) (kg) Agg. (kg) 4 Specific gravity 2.13 (kg)

0.40 1:1.72:2.28 450 772.58 1026 180 TABLE III PHYSICAL PROPERTIES OF FINE & COARSE AGGREGATE. 0.45 1:2.03:2.56 400 814.97 1026 180 Aggregate Fineness Bulk Density Specific 0.50 1:2.35:2.85 360 847.73 1026 180 Modulus (kg/m3) Gravity

Fine Agg. 3.64 1696 2.58 0.55 1:2.67:3.13 327 874.54 1026 180 Coarse Agg. 7.07 1770 2.87

III. EXPERIMENTAL WORK TABLE VI COMPACTION FACTOR FOR DIFF. CONCRETE MIX In this study, workability of fresh concrete and mechanical performance of hardened concrete were examined. Both tests Type A B C D E were conducted using five sample group as shown in table 4. Concrete were prepared at four water to cementitious W/C material ratios – 0.40, 0.45, 0.50, 0.55. For each of above 0.40 0.78 0.8 0.827 0.835 0.842 sample groups, concrete raw materials were batched and mixed for approximately 10 minutes in . 0.45 0.8 0.812 0.819 0.825 0.834 To find out workability of fresh concrete, compaction factor test was carried out for each mix. 0.50 0.815 0.84 0.852 0.857 0.863

0.55 0.87 0.88 0.912 0.92 0.915 TABLE IV COMPOSITION OF DIFFERENT TYPES OF

Type Composition Table VI shows that for type A cement, as w/c ratio increased, compaction factor increased due to decrease in A 100% OPC amount of cement content, but for type B, C, D &E, for same B 88% OPC + 10% MK + 2% Iron Oxide. w/c ratio and same amount of cement as per table 6, compaction factor increases due to addition of activated fly C 78%OPC + 10% MK + 10% FA + 2% ash. Figure 1 shows various compaction factors for five types Iron Oxide of cement. D 68%OPC + 10% MK + 20% FA + 2% Iron Oxide The result for harden concrete in form of compressive E 58%OPC+ 10% MK + 30% FA + 2% strength of concrete cubes at 3,7,14,28 & 56 days are Iron Oxide summarized in table 7. Table 7 shows that when OPC is replaced by 42%, i.e. 30% For above all types of cement, four mix designs were prepared with fly ash, 10% with metakaolin and 2% with iron oxide, with w/c ratio 0.40, 0.45, 0.50, 0.55 and constituent of although we get higher strength that is for w/c ratio of 0.4, materials for different w/c ratio are summarized in table 5. 0.45, 0.5, & 0.55 which is higher than M-25 grade, which shows the effect of fly ash and metakaolin on strength of concrete. IV. RESULTS AND DISCUSSION Result shows that compressive strength with addition of Five mixes of cement were prepared and for each type four pozzolanic materials at 7 days and 14 days is lower than M25 w/c ratios were used. The result obtained for fresh concrete in grade OPC strength but equal at 28 days and higher at 56 days. form of compaction factor test is summarized in table 6.

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India National Conference on Recent Trends in Engineering & Technology

TABLE VII CUBE COMPRESSIVE STRENGTH OF CONCRETE MIX

Mix Compressive strength (N /mm2) 3days 7days 14days 28days 56days #A 36.17 38.22 45.03 51.25 62.74 #B 25.48 33.15 36.73 37.33 49.57 #C 22.32 28 33.43 40.42 47.29 #D 17.035 24.63 31.72 38.20 41.70 #E 17.55 23.37 30.29 36.32 40.67

!A 26.66 33.03 37.035 46.22 59.33 !B 26.36 27.18 34.33 47.70 45.55 !C 18.66 22.99 29.77 33.34 41.95 !D 15.04 20.78 26.96 32.29 39.53 !E 14.071 17.89 26.15 27.61 35.27

Fig. 1 Compaction factor of different concrete mix *A 20.29 30.51 38.07 41.92 46.66 *B 19.70 25.33 29.89 41.70 45.40 *C 13.62 15.25 20.88 23.93 32.80 V. CONCLUSION *D 11.46 14.41 23.36 28.93 31.6 *E 9.53 12.11 20.85 23.05 25.78 When OPC is replaced up to 42% in concrete, it gives strength up to 40.67 N/mm2 in 0.40 w/c, and in 0.55 w/c ratio it !!A 14.81 25.33 26.36 29.15 43.22 gives strength up to 25.47 N/mm2 at 56 days, so even in 0.55 w/c ratio we can get concrete of M25 grade level. !!B 13.77 22.10 23.55 32.29 34.96 Increase in percentage of pozzolanic material, compaction !!C 14.36 18.81 24.63 29.34 33.68 factor is also increased which gives the improvement in !!D 11.64 16 25.91 29.15 32.35 workability of concrete due to ball bearing effect of activated !!E 10.02 14.51 15.95 20.15 25.47 flyash. Note: By replacing OPC up to 42% with fly ash(30%), metakaolin # Concrete mix with 0.40 w/c ratio (10%) and iron oxide (2%), cost of concrete is reduced which ! Concrete mix with 0.45 w/c ratio is helpful to make economic concrete. *Concrete mix with 0.50 w/c ratio In general, we can conclude that addition of pozzolanic !! Concrete mix with 0.55 w/c ratio materials like (activated flyash, metakaolin, iron oxide) as A,B,C.... indicates types of cement used in concrete mix replacement of OPC gives higher strength at 56 days and also improves the workability of concrete with lower w/c ratio.

Fig. 2 Compaction factor test apparatus Fig. 3 Compressive strength of concrete (0.40 w/c)

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India National Conference on Recent Trends in Engineering & Technology

Fig. 6. Compressive strength of concrete (0.55 w/c) Fig. 4 Compressive strength of concrete (0.45 w/c)

REFERENCES

[1] Shetty M.S., “Concrete Technology Theory and Practice”, S.Chand & Company, New Delhi. [2] ASTM C 33-93, Standard Specification for Aggregates [3] A.M.Poppe, G. Baert and N.De Belie “Strength and Durability of high-volume Flyash Concrete.” [4] Chi sun poon, Lik Lam and Yuk Lung Wong, “Effect of Flysah and Silica Fume on Interfacial Porosity of Concrete Shrikage”, journal of materials in civil engineering/ August 1999, pp197-205. [5] Jiping Bai, Albinas Gailus “Consistency of Flyash and Metakaolin Concrete”. [6] Justice J.M. et Al. “Comparison of Two Metakaolin and a Silica Fume used as Supplementary Cementitious Materials” Article from Proc. Seventh International Symposium on Utilization of High Strength Performance Concrete, Washington D.C., june 20-24, 2005. [7] Prabir C. Basu, “Flyash Base Concrete” Civil Engg. Department, Atomic Energy Board, Mumbai, CE&CR, February 2009, pp – 78- 86. Fig. 5 Compressive strength of concrete (0.50 w/c) [8] Shaikh Javed, “Processed Flyash For Superior Concrete”, CE&CR February 2009, pp – 62 – 68. [9] Tiwari A.K, Jha D.N. & Venkateshwaran D. “Property of High Strength Concrete with High Volume Flyash” ICI journal, vol 6, april – june 2005.

13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India National Conference on Recent Trends in Engineering & Technology

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13-14 May 2011 B.V.M. Engineering College, V.V.Nagar,Gujarat,India