Triple Blending of Cement Concrete With Fly Ash and Ground Granulated Blast Furnace Slag

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1 IJEAR Vo l. 4, Is s u e Sp l-2, Ja n - Ju n e 24 Triple Blending of Cement Concrete With Fly Ash and Ground Granulated Blast Furnace Slag K.V.Pratap, 2 M.Bhasker, 3 P.S.S.R.Teja,3 Dept. of Civil Engineering, Vignan University, Vadlamudi, Guntur, AP, India 2 Dept. of Civil Engineering, Vasavi College of Engineering, Hyderabad, AP, India Abstract Concrete is the key material used in various types of construction, from the flooring of a hut to a multi-storied high rise structures. Concrete is one of the versatile heterogeneous materials. With the advent of concrete civil engineering has touched highest peak of technology. It is the material of choice where strength, durability, impermeability, fire resistance and abrasion resistance are required. The properties of concrete mainly depend on the constituents used in concrete making. The main aim of the present study is to determine the compressive strength, split tensile strength and flexural strength of concrete mix of M6 grade, with partial replacement of cement with Ground Granulated Blast furnace Slag and FLY-ASH. Our study includes the concept of triple blending of cement with and FLY-ASH, this triple blend cement exploits the beneficial characteristics of both Pozzolanic materials in producing a better concrete. Keywords Concrete, Fly Ash, Ground Granulated Blast Furnace Slag, Super Plasticizer, and Compressive I. Introduction In the last millennium concrete has demanding requirements both in terms of technical performance and economy while greatly varying from architectural masterpiece to the simplest of utilities. Concrete is a material with which any shape can be cast and with equal strength or rather more strength than the conventional building stones. Cement concrete is one of the seemingly simple but actually complex materials. The properties of concrete mainly depend on the constituents used in concrete making. The main important material used in making concrete is cement, sand, crushed stone and water. The properties of sand, crushed stone and water, if not used as specified, cause considerable trouble in concrete. In addition to this workmanship, quality control and methods of placing also plays the leading role on the properties of concrete. Concrete is considered as durable and strong material. Reinforced concrete is one of the most popular materials used for construction around the world. Reinforced concrete is exposed to deterioration in some regions especially in coastal regions. There for researchers around the world are directing their efforts towards developing a new material to come this problem. Invention of large construction plants and equipments around the world added to the d use of material. This scenario led to the use of additive materials to improve the quality of concrete. II. Materials A. Cement Ordinary Portland cement 53 grade brand conforming to Indian Standard is used in the present investigation. The cement is tested for its various properties as per Indian Standard code. B. Fine Aggregate The locally available sand is used as fine aggregate in the present investigation. The sand is free from clayey matter, salt and organic impurities. The sand is tested for various properties like specific gravity, bulk density etc., in accordance with Indian Standard (28). C. Coarse Aggregate Machine crushed angular granite metal from the local source is used as coarse aggregate (confined to Indian Standard: ). It is free from impurities such as dust, clay particles and organic matter etc. The coarse aggregate is also tested for its various properties. D. Admixtures Fly ash: In this project the fly ash used belongs to class F and was brought from VIZAG THERMAL POWER STATION, VIJAYAWADA. Ground Granulated Blast Furnace Slag: Ground granulated blast furnace slag is by-product from the blast furnaces used to make iron. The major properties of the constituent materials were given in Table. Table : Properties of the constituent materials of concrete Materials Properties Ordinary Portland Specific gravity : 2.99 Cement Maximum Size : 4.74mm, Fine aggregate Specific gravity : 2.68, Fineness Modulus : 2.78 Size : 2.5mm-2mm, Coarse Aggregate Specific Gravity : 2.64, Fineness Modulus : 7.4 Water P H =7, Density=kg/m 3 Fly ash, Ground Admixtures Granulated Blast Furnace Slag Super plasticizer Conplast SP43 III. Experimental Investigation General: An experimental study is conducted to find out the compressive strength, split tensile strength and flexural strength of concrete at 7days and 28days. In concrete the partial replacement of cement by Fly ash and are varied from (4+6),( 8+2),( 2+8) and (6+4) by weight. M6 grade of concrete is designed according to DOE (Direct Elimination) method. Mix proportion for control mix concrete is shown in Table International Journal of Education and applied research

2 IJEAR Vo l. 4, Is s u e Sp l-2, Ja n - Ju n e 24 Table 2: Mix Proportions of Concrete Finalised Mix Control mix of M6 (DOE method) Cement (Kg/m 3 ) Fine Aggregate (Kg/m 3 ) Coarse Aggregate (kg/m 3 ) Water (l/m 3 ) Work Plan The present experimental programme includes casting and testing of specimens for Compression, Split tensile and Flexural strength. Specimens are prepared for M6 grade of concrete. Total of 2 specimens (shown in table 3) with various percentages of Fly ash and Ground Granulated Blast Furnace Slag are casted. Table 3: Number of specimens casted for each mix Admixtures Fly ash () () 7 Days 28 Days No. of specimens No. of specimens Cubes Cylinders Prisms Cubes Cylinders Prisms Mixing Machine mixing is adopted throughout the experimental work. First the materials cement, Fly ash, Ground Granulated Blast Furnace Slag, fine aggregate, coarse aggregate are weighed exactly. First the cement, Fly ash and Ground Granulated Blast Furnace Slag are blended with hand and then fine; coarse aggregate is added to this and thoroughly mixed. Water is weighed exactly and added to the dry mix and entire mix is thoroughly mixed till uniformity is arrived. Casting of Specimens For casting the cube, standard Cast iron metal moulds of size 5 x 5 x 5mm have been used. Whereas cylinders and prisms of size 5x3mm and xx5mm are casted respectively. The moulds have been cleaned of dust particles and applied with mineral oil on all sides, before concrete is poured into the mould. Thoroughly mixed concrete is filled in to mould. Whole casting procedure is confined to Indian Standard: to that as cast in the compression testing machine. According to the standard specifications the load on the cube was applied at standard constant rate up to the failure of the specimen and the ultimate load was noted. Cube compressive strength was tested and the results were tabulated. Split tensile strength test: The test is carried out by using the cylindrical specimens. Flexural strength test: This test was conducted on the flexural testing machine. The load was applied at the middle third points of the effective span of the flexural beam. IV. Results A. General 6 Cubes, 3 prisms and 3 cylinders are casted with M6 grade concrete. Twenty percent of cement is replaced by a combination of fly ash and Ground Granulated Blast Slag in different proportions. Compressive strength of cube specimen at 7 days and 28days, flexural strength of prisms at 7 days 28 days and split tensile strength of cylinder at 7 days and 28days are noted below and also their comparisons are also noted from table 4 to table 2. Table 4: Compressive of M6 Grade Concrete Cubes With Various Percentages of Fly ash and by replacement with cement by weight of Compressive of M6 (N/ mm²) 7 Days 28 Days Table 5: Variation of Compressive at 7 Days with various Fly ash and Curing the Specimens After casting, the moulded specimens are stored in the laboratory free from vibration, in moist air and at room temperature for 24 hours. After this period, the specimen are removed from the moulds and immediately submerged in the clean fresh water of curing tank. The curing water is renewed after every 5 days. The specimens are cured for 7 and 28 days in present work. 7 Days Compressive in (N/mm²) Testing of Specimens The specimens cured as explained above are tested as per Indian Standard: after removal from the curing tank and allowed to dry under shade. Compressive strength test: In compressive strength test the cube specimen was placed with the cast faces of the cubes at right angles International Journal of Education and applied research 55

3 IJEAR Vo l. 4, Is s u e Sp l-2, Ja n - Ju n e Table 6: Variation of Compressive at 28 Days with various Fly ash and 28 Days Compressive in (N/mm²) Table 9: Variation of Flexural at 28 Days with various Fly ash and 28 Days Flexural in (N/mm²) Table 7: Flexural of M6 Grade Concrete Prism with Various Percentages of Fly ash and at 7 days and 28 days Flexural Of M6 (N/mm²) 7 Days 28Days Table 8: Variation of Flexural at 7 Days with various of Fly ash and 7 Days Flexural in (N/mm²) Table : Split Tensile of M6 Grade Concrete Cylinder with Various Percentages of Fly ash and Split Tensile Of M6 (N/mm²) 7Days 28 Days International Journal of Education and applied research

4 IJEAR Vo l. 4, Is s u e Sp l-2, Ja n - Ju n e 24 Table : Variation of Split Tensile at 7 Days with various Fly ash and 7 Days Split Tensile in (N/ mm²) Fig. 2: Percentage Increase Over Vs Percentage of FLYASH and at 7 Days Compressive Table 2: Variation of Split Tensile at28 Days with various Fly ash and 28 Days Split Tensile in (N/mm²) Fig. 3: Percentage Increase Over Vs Percentage of FLYASH and at 28 Days Compressive Fig. 4: Flexural of M6 Grade Prism With Various Percentages of FLYASH and at 7 Days and 28 Days Fig. : Compressive (N/mm 2 ) Vs Percentage of FLYASH and at 7 Days and 28 Days Fig. 5: Percentage Increase Over Vs Percentage of FLYASH and at 7 Days Flexural International Journal of Education and applied research 57

5 IJEAR Vo l. 4, Is s u e Sp l-2, Ja n - Ju n e 24 V. Conclusion. The compressive strength, flexural strength and split tensile strength of concrete are improved with the addition of fly ash and as partial replacement to cement. 2. The compressive strength of concrete is d by a maximum of.3 at 28days with (4+6) replacement. 3. The flexural strength of concrete is d by a maximum of.74 at 28days with (4+6) replacement. 4. The split tensile strength of concrete is d by a maximum of 23. at 28 days with (4+6) replacement. Fig. 6: Percentage Increase Over Vs Percentage of FLYASH and at 28 Days Flexural Fig. 7: Split Tensile (N/mm 2 ) Vs Percentage of FLYASH and at 7 Days and 28 Days References [] M.V. Krishna Rao, P. Rathish Kumar, Azhar M. Khan, A Study on the influence of curing on the strength of a standard grade concrete mix,architecture and Civil Engineering, Vol. 8, No, 2, pp [2] M.S.Shetty, Concrete Technology, S.Chand&Company limited, 26. [3] N.Krishnaju, Design of Concrete Mix, CBS Publishers, 985. [4] P.K.Mehta, J.M.M.Paulo, Concrete Microstructure Properties and Materials, McGraw Hill Publishers, 997. [5] A.M.Neville, Properties of concrete, English Language Book Society, 998. [6] IS , Indian Standard Specification for pozzolanas, bureau of Indian Standards. [7] IS , Indian Standard Methods of physical tests for hydraulic cement. [8] IS , Indian standard methods for aggregates for concrete of Indian standards, NEW DELHI. [9] IS , Indian standard specification on for coarse and fine aggregate for natural sources for concrete, 2nd revision, Bureau of Indian standards New Delhi. [] IS , Method of test for strength of concrete. [] IS 7869(part 2), Indian standard Specification for Admixtures for concrete, 98. [2] IS 456-2, Plain and Reinforced Concrete Indian Standard Specification. Fig. 8: Percentage Increase Over Vs Percentage of FLYASH and at 7 Days Split Tensile K.V.Pratap, M.Tech (Structural Engineering) from National Institute of Technology, Trichy, Tamilnadu, India. (2-3). B.E (Civil Engineering) from Vasavi College of Engineering, Ibrahimbagh, Hyderabad, Andhra Pradesh, India. (27-). Fig. 9: Percentage Increase Over Vs Percentage of FLYASH and at 28 Days Split Tensile 58 International Journal of Education and applied research