International Journal of Civil Engineering and Technology (IJCIET), ISSN INTERNATIONAL JOURNAL OF CIVIL ENGINEERING AND

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1 INTERNATIONAL JOURNAL OF CIVIL ENGINEERING AND TECHNOLOGY (IJCIET) ISSN (Print) ISSN (Online) Volume 4, Issue 2, March - April (2013), pp IAEME: Journal Impact Factor (2013): (Calculated by GISI) IJCIET IAEME EFFECT OF UNPROCESSED STEEL SLAG ON THE STRENGTH OF CONCRETE WHEN USED AS FINE AGGREGATE Riyaz Khan 1, Prof.S.B.Shinde 2 1 Master of Civil Structures, Faculty of Engineering, Jawaharlal Nehru Engineering College, Aurangabad , Maharashtra, India 2 H.O.D. Civil Engineering, Jawaharlal Nehru Engineering College, Aurangabad, Maharashtra, India. Dr.Babasaheb Ambedkar Marathwada University, Maharashtra, India ABSTRACT Fine aggregate is a natural and conventional source which is used in a massive quantity Fine aggregate is a natural and conventional source which is used in a massive quantity for the concrete resulting the reduction of bed levels and dryness in pride of our nation- rivers, to over-come this problem slag is the sound choice in favour of ecology when used as fine aggregate in rapid concrete sector. Steel Slag is produced locally in great amounts, creates problems for the environment when disposed. This work includes the determination of different properties of locally available steel slag & utilization of steel slag in concrete by replacing it partially and fully by fine aggregate keeping the other parameters constant. Various strengths considered for investigation are compressive Strength, flexural Strength and split tensile strength on M20 grade of concrete with constant 0.5 w/c ratio. Steel slag replacement of 0,20, 40, 60, 80 & 100% are used. The best results are obtained for replacement ratio of 60%. Therefore, the use of steel slag in concrete would enhance of the strength of concrete. Key Words: Fine aggregate, steel slag, concrete, strength. 1. INTRODUCTION Steel making is a strategic requirement of the economy of developing nation like India. Many steel plants have been set up in our country. However, production of iron and steel is associated with the generation of solid waste materials like slag. Big steel plants in India generate about 29 million tonnes of waste material annually. In addition, there are several medium and small plants all over the country. Slag reduces the porosity and 231

2 permeability of soil, thus increasing the water logging problem. It causes respiratory ailment among nearby residents, contaminates ground water, and adversely affects the landscape of the area. Industrial area around major cities there are several small and large scale industries wasting nearly thousands of metric tonne steel slag daily. Problem of disposing this slag is very serious which can be reduced by utilizing steel slag for concrete construction. The final properties of concrete, such as strength, durability and serviceability depend mainly on the properties and the quality of the materials used. Locally, waste materials from the steel industry are produced in high amounts and shapes ranging from large boulders to dust. They are considered a headache for both the factories and the environment. The factories have to pay huge amounts for the disposal of these materials. The disposal of these materials will have a negative impact on the environment. Steel slag can be used in conventional concrete to improve its mechanical, physical, and chemical properties. 2. MATERIAL PROPERTIES INVESTIGATED FOR THIS RESEARCH Table 1:- Material Properties 1 Nominal Max.Size of coarse aggregate 20 mm 2 Slump range (Medium) mm IS (Pg.02) 3 Finness Modulus Of Fine Aggregate 2.88 Confirming to zone II (IS ) 4 Finness Modulus Of Steel Slag aggregate 2.86 Confirming to zone II (IS ) 5 Finness Modulus Of Coarse Aggregate 5.12 Confirming to zone II (IS ) 6 Specific Gravity Of Fine Aggregate Specific Gravity Of Steel Slag aggregate Specific Gravity Of Coarse Aggregate Specific Gravity Of Cement Water Absorption of fine aggregates 4.7 % 11 Water Absorption of coarse aggregates 1.65 % 12 Water Absorption of steel slag 4.6 % 232

3 2.1 Chemical composition and physical properties of steel slag used in the study Table 2:- Chemical Composition of Steel Slag Table 3:- Physical Properties of Steel Slag 3. EXPERIMENTAL PROGRAM Materials used in this study were OPC 53 grade cement confirming to IS 8112 and fine aggregate and coarse aggregate confirming to IS The cement and aggregate were tested to fulfill the IS requirements. Designed concrete mix of M-20 grade having mix proportion 1:1.90:2.96 with w/c ratio 0.5 same for different percentages of steel slag 0%,20%,40%,60%,80%,100% were used. The concrete ingredients namely, cement and coarse aggregates and steel slag were first mixed in the dry state and water was added last. Beams of size 700x150x150mm for flexural strength, Cylinders of size 150mm diameter x 300mm length for split tensile strength, Cubes of size 150x150x150 mm for compressive strength were cast replacing 20,40,60,80 & 100% by weight of fine aggregate. In flexural and shear test beam break into two part by two point loading. All the samples were watered cured for 14 days and 28 days. For each batch of slag percentage replacement 6 specimens were cast. Details of the experimental investigation of effect of different percentages replacement of fine aggregate by steel slag are given elsewhere. 233

4 3.1 Test conducted UTM used as a test set up for carrying out all the test on addend concrete. The test were carried out for the following properties, viz, flexural, shear, prism split tensile and compressive strengths. A standard test procedure is followed for each test and strength performance of hardened concrete is studied Compressive strength This strength was determined by carrying out cube compressive test of size 150x150x150 mm on UTM. as shown in figure1. Fig1:- Test arrangement for Compressive Test. The Compressive strength calculated by formula fcu= P/A Where fcu=compressive strength of cube, MPa or N/mm2 P= Compressive load at failure, N A= area of loading face of cube, mm2 The Compressive strength results are shown in table4: Table 4.(Compressive strength) Slag % 0% 20% 40% 60% 80% 100% Compressive strength at 14 days (N/mm 2 ) Compressive strength at 28 days (N/mm 2 )

5 3.1.2 Flexural strength For determining this strength each specimen of size 700 mm X 150 mm X 150 mm was supported over a span of 600 mm and a two point load was applied at the centre of span as shown in figure 1. The deflection of the beam under the load was recorded up to the first crack. All the beams were loaded up to failure. Fig.2 Arrangement for Loading of Flexure Test Specimen 235

6 The flexural strength is calculated by the formula (From IS ) Where, f b = Flexural strength, MPa or N/mm 2 b = measured width in mm of the specimen, d = measured depth in mm of the specimen at the point of failure, l = length in mm of the span on which the specimen was supported, and p = maximum load in N applied to the specimen. The flexural strength results are given in table 5: Table 5.(Flexural Strength) Slag % 0% 20% 40% 60% 80% 100% Flexural strength at 14 days (N/mm 2 ) Flexural strength at 28 days (N/mm 2 )

7 3.1.3 Split tensile strength A prism split tensile test method has been used to determine the split tensile strength of concrete.. In this test, compressive line load are applied along vertical symmetrical plane setting of tensile stresses normal to the plane which cause the splitting of specimen. The splitting tensile strength have been computed from the following expression confirming to IS 5816 : Fig.3 Testing arrangement The Split tensile strength is calculated by the formula Where, Fct= Splitting tensile strength, N/mm 2. d = measured diameter in mm of the cylinder. l = length in mm of the cylinder. and p = maximum load in N applied to the specimen. The Splitting tensile strength results are given in table 6: for Split tensile test Table 6. (Split tensile Strength) Slag % 0% 20% 40% 60% 80% 100% split tensile strength at 14 days (N/mm 2 ) split tensile strength at 28 days (N/mm 2 )

8 4.0 TEST RESULTS AND DISCUSSION Compressive strength Results of compressive strength are presented in Table 4. Inclusions of steel slag in concrete improve the compressive strength. The 28 days strength of 60 % replaced slag increases the compressive strength. Test showed an increase of 25% of compressive strength compared to nominal mix without steel slag. Flexural Strength The average flexural strength of Steel slag concrete at the age of 14 days and 28 days is shown in Table 5. Results shows that the replacement of steel slag with 60% by fine aggregate gives highest flexural strength. A 12% increase in flexural strength was observed compared to concrete without steel slag. Split tensile strength Results from Table 6 Shows that cylinder split tensile strength of concrete increases considerably with increase in steel slag percentage. The 60% replacement gives maximum increase in split tensile strength also. Splitting tensile strength showed an exceptional 56% increase when compared to concrete without steel slag. From the above results it can be concluded that 60 % replacement of fine aggregate with steel slag gives desirable results and can be considered for the construction practices. 238

9 REFERENCES 1. Hisham Qasravi,Faisal shalabi,ibrahim Asi, Effect of unprocessed steel slag on the strength of concrete when used as fine aggregate, Proceedings of the ACI-KC Second International Conference, March 12-14, 2007, Kuwait, p Hisham Qasravi,Faisal shalabi,ibrahim Asi, Use of low Cao unprocessed steel slag in concrete as fine aggregate, Construction and Building Materials 23 (2009), p Alizadeh R., Chini M., Ghods P., Hoseini M., Montazer Sh., M. Shekarchi M. (1996) Utilization of electric arc furnace slag as aggregates in Concrete, Environmental Issue, CMI report Tehran Asi I., Qasrawi H. and Shalabi F., 2005 Use of steel slag in engineering projects, Progress Report No. 1 submitted to United Iron and Steel Manufacturing Company. 5. Geiseler, J. (1999) Slag-approved material for better future, Proceeding of International Symposium on the Utilization of Metallurgical Slag (ISUS 99),Beijing,China. 6. Kamal, M., Gailan, A. H., Haatan, A., Hameed, H. (2002), Aggregate made from industrial unprocessed slag, Proceeding of the 6th. International Conference on Concrete Technology for Developing Countries, Amman, Jordan Manso J., Gonzalez J and Polanco J. Electric furnace slag in concrete, (2004), Journal of Materials in Civil Engineering, ASCE, November/December, pp M. Venu and P. N. Rao, Study of Rubber Aggregates in Concrete: An Experimental Investigation, International Journal of Civil Engineering & Technology (IJCIET), Volume 1, Issue 1, 2010, pp , ISSN Print: , ISSN Online: P.J.Patel, Mukesh A. Patel and Dr. H.S. Patel, Effect of Coarse Aggregate Characteristics on Strength Properties of High Performance Concrete using Mineral and Chemical Admixtures, International Journal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 2, 2013, pp , ISSN Print: , ISSN Online: