USE OF WASTE CONDUCTIVE STEEL RESIDUE IN CONCRETE PROVING BENEFICIAL FOR DE-ICEING OF PAVEMENTS

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 6, Issue 12, Dec 2015, pp , Article ID: IJCIET_06_12_007 Available online at ISSN Print: and ISSN Online: IAEME Publication USE OF WASTE CONDUCTIVE STEEL RESIDUE IN CONCRETE PROVING BENEFICIAL FOR DE-ICEING OF PAVEMENTS Abid Ahmad Sofi, S. M. Iqbal, Suhail Ahmad Mir, M. Vekas Wani Civil Engineering Graduate Students, IUST, Awantipora Kmr. Aarif Manzoor, Er. M. Iqbal Mirza Assistant Professor, Department of Civil Engineering, IUST, Awantipora Er. Aeijaz Masoodi Road Research Officer, KGP Sgr. ABSTRACT The road connectivity of Jammu and Kashmir state with the rest country (India) is possible through NH-1. During winters, the traffic movement is seen off the roads due to accumulation of heavy snow and one province i.e, Kashmir of the state seems cut off from the country. Every year Government of the state is spending very huge amount for snow clearance by conventional methods like using snow cutters, chemicals (salt) etc. These methods result what is called Detoriation of pavements by removal of top surface of flexible pavements and corrosion of reinforcement by chemicals in rigid pavements.the paper highlights the one time solution of the above problem by using the steel residue obtained in huge quantities from steel industries.the material is used in concrete as a homogeneous mix at the construction stage of rigid pavements over which insulated bitumen layer is placed. During the working stage, when there is the prediction of snowfall the current is applied in advance which keep the pavement warm and no accumulation of snow takes place. Key words: Steel Residue, Sustainability, Resistivity, De-Iceing, Rigid Pavement. Cite this Article: Abid Ahmad Sofi, S. M. Iqbal, Suhail Ahmad Mir, M. Vekas Wani, Aarif Manzoor, Er. M. Iqbal Mirza and Er. Aeijaz Masoodi, Use of Waste Conductive Steel Residue In Concrete Proving Beneficial For De- Iceing of Pavements. International Journal of Civil Engineering and Technology, 6(12), 2015, pp editor@iaeme.com

2 Use of Waste Conductive Steel Residue In Concrete Proving Beneficial For De-Iceing of Pavements 1. INTRODUCTION Conventional concrete is not electrically conductive. A hydrating concrete consists of pore solution and solids, including aggregates, hydrates and unhydrated cement. Conduction of electricity through concrete may take place in two ways:electronic: Electronic conduction occurs through the motion of free electrons in the conductive media. Electrolytic: Electrolytic conduction takes place by the motion of ion s in the pore solution in the fresh state. Controlled resistivity materials are used for controlled electrical conduction, static charge dissipation, lightning protection, and electromagnetic interference shielding in electronic, mechanical, structural, chemical applications and electrically powered transit lines. In particular, controlled resistivity ceramics, such as alumina-matrix composites containing electrically conducting particulates filler are used as substrates for handling semiconductor wafers, which require static protection [1]. They are also used in form of charge dissipating coating to improve the break down voltage of high power, high vacuum devices. In addition, controlled resistivity ceramics in the form of tiles are used for antistatic floors [2]. It was found that Electric resistivity of the concrete is infinite as there is no conducting medium within the concrete mass for the current to flow. When a conducting material i.e, waste steel residue is mixed with ingredients of concrete, its electrical resistivity increases upto some percentage of additive and then decreases as the continuous path for current flow is set up by steel particles [3].Controlled electrical resistivity materials are typically in the form of composite materials with an electrically insulating matrix and electrically conductive discontinuous filler, which can be particulate or fibrous. The higher filler content, lower resistivity of composite. These composites include those with polymer, ceramic and cement matrices [4,5]. Compressive strength of concrete is dependent on the W/C ratio. The higher the ratio the lower is the strength. Electrical resistivity of concrete decreases almost linearly with increasing W/C ratio for a given cement content and therefore resistivity can be diagnostic of the compressive strength [6]. Xie et al used steel and carbon fibres as the conductive media and investigated the effect of fiber size on the percolation threshold, which was found to increase with decreasing fiber length. More short fibres than long fibres were required to create a conductive media within the concrete matrix. Conduction through hardened concrete depends on movement of electrons which requires a good contact between conductive particles. Using longer fibres could reduce the minimum contact required [7]. Approaches to improving the electrical conductivity of a concrete mix include: Use of conductive aggregates such as iron ore, raw slag etc. Increasing the conductivity of the cement paste by adding conductive materials such as steel shavings, steel or carbon fibres, etc. In this research, fine aggregates were partially replaced by waste steel residue as 1.5%, 3%, 4.5%, 6% and 7.5% by weight.the replaced waste steel residue consists of all three categories of steel shaving, steel-fibres, steel powder in equal proportions.the concrete in fresh state is checked for workability by doing Slump test and Concrete specimens were tested for compressive strength, resistivity by four-probe method and Temperature rise of the specimen. The results obtained were compared with results of normal M-30 concrete mix and it was found that maximum increase in compressive strength occurred for the concrete mix containing 3%steel residue as fine aggregate. With increase in steel residue content, resistivity and the temperature rise increases and 3% replacement is considered as optimum value because upto this 67 editor@iaeme.com

3 Abid Ahmad Sofi, S. M. Iqbal, Suhail Ahmad Mir, M. Vekas Wani Aarif Manzoor, Er. M. Iqbal Mirza and Er. Aeijaz Masoodi value no electric shocks are felt and after this value sensitive shocks are observed. The rate of De-Iceing is optimum at 3% steel residue in rigid pavements. 2. MATERIALS USED 2.1. Cement and Aggregates Khyber ordinary Portland cement of 43 grade confining to IS 8112 [8] was used throughout the work. Fine aggregates used throughout the work comprised of clean river sand with maximum size of 4.75mm conforming to zone II as per IS [9] with specific gravity of 2.6. Coarse aggregates used consisted of machine crushed stone angular in shape passing through 20mm IS sieve and retained on 4.75mm IS sieve with specific gravity of Steel residue The waste material i.e. steel residue in this study is collected from Himalayan Rolling Steel Mill, SIDCO Complex, Rangreth srinagar.after the collection of the material, it was categorized into three categories i.e, Steel fibres(fraction retained on 10mm IS Sieve),steel shaving(fraction passing 10mm and retained on 4.75mm IS-Sieve),steel powder(passing 4.75mm and retained on 2.36mm IS-Sieve). Figure 1. Shows the three catagories (a)steel fibres (b) steel shaving (c) steel powder Figure 1 Three catagories of steel residue 3. WORK AND EXPERIMENTAL METHODOLOGY 3.1. Mix Proportion The concrete mix design was proposed by using IS [10]. The grade of concrete used was M-30 with water to cement ratio of 0.45(inclusive of free moisture in aggregates). The design mix obtained from the trial mix of the ingredients is 1:1.346:2.44. The mixture proportions used in laboratory for experimentation are shown in TABLE Test on Fresh Concrete The workability of all concrete mixtures was determined through slump test utilizing a metallic slump mould. The difference in level between the height of mould and that of highest point of the subsided concrete was measured and reported as slump editor@iaeme.com

4 Use of Waste Conductive Steel Residue In Concrete Proving Beneficial For De-Iceing of Pavements Figure 2 Slump measurement The slump tests were performed according to IS [11] Tests on hardened concrete From each concrete mixture, cubes of size 150mm x 150mm x 150mm have been casted for the determination of compressive strength. The concrete specimens were cured under normal conditions as per IS [11] and were tested at 7 days and 28days for determining compressive strength as per IS [12] Tests for Resistivity (ohm-cm) The Resistivity of the concrete is found by four-electrode method refers to the four electrodes applied to conductive concrete cube as shown below. Figure 3 Determination of Resistivity by Four-probe method. The four electrodes are embedded in the conductive concrete in equidistant mode. The two electrodes inside is connected to voltmeter and the two electrodes outside are connected to ammeter. This method makes voltage and current of measuring electrodes separate. Besides, the outside electrodes are supplied by the DC source and the value of voltage and current are recorded [13] editor@iaeme.com

5 Abid Ahmad Sofi, S. M. Iqbal, Suhail Ahmad Mir, M. Vekas Wani Aarif Manzoor, Er. M. Iqbal Mirza and Er. Aeijaz Masoodi Figure 4 Principle of four probe method The resistivity is then calculated using the following equation: ρ = where, ρ is resistivity (ohm.cm), d is distance between inner electrodes (cm), V is voltage between probes P1, P2 (volts), I is current between probes C1, C2(amperes) Test for Temperature The rise in Temperature of the concrete is checked by means of a Thermometer after half an hour (30 min.) from the instant of applied current. 4. RESULTS AND DISCUSSION 4.1. Concrete in Green state The slump values of all the mixtures are represented in TABLE 1. The slump is increased with the increase in steel residue (S.R). No, water is absorbed by S.R as compared to sand which absorbs some water, and thus improving the workability of concrete mix. Slump was continuously increasing with the increase in S.R. The variation of slump with S.R is depicted in Figure Compressive strength The compressive strength tests are presented in TABLE 2. Compressive strength tests were carried out at 3, 7 and 28 days. An increase in compressive strength was observed up to 3% replacement of fine aggregates by steel residue and there after decreasing. The maximum compressive strength measured was 8.4% more than that of reference mix at 28 days corresponding to concrete mix containing 3% steel residue in place of fine aggregates. Compressive strength (C.S) for concrete mix with 7.5% content was found to be less than that of reference mix. Figure.6 presents compressive strength of all mixtures at 3, 7 and 28 days respectively Resistivity and Temperature results The resistivity and temperature test results are presented in TABLE 3.These tests are carried out after 28 days curing period. The resistivity and the temperature rise increases with the increase in steel residue and the maximum value is observed at 3%. Figure.7 and 8 presents the resistivity and temperature of all mixtures at 28 days respectively editor@iaeme.com

6 Use of Waste Conductive Steel Residue In Concrete Proving Beneficial For De-Iceing of Pavements S.R (%) W/C TABLE 1 Mix Proportion, Slump (mm) Determination. Water Cement F.A S.R C.A Slump (mm) TABLE 2 Compressive Strength Test results. S.NO S.R (%) Avg. 3days Avg. 7days Avg. 28days (N/ ) (N/ ) (N/ ) TABLE 3 Resistivity and Temperature results. S.NO S.R (%) RESISTIVITY (Ohm-cm) TEMPT. RISE ( ) x x x x x x Slump(mm) S.R(%) Figure 5 Variation of slump with S.R content. SLUMP VALUE 71 editor@iaeme.com

7 Temperature rise ( C) Resistivity (Ohmcm)X10^3 C.S (N/mm^2) Abid Ahmad Sofi, S. M. Iqbal, Suhail Ahmad Mir, M. Vekas Wani Aarif Manzoor, Er. M. Iqbal Mirza and Er. Aeijaz Masoodi Days 7 Days 28 Days S.R (%) Figure 6 Variation of C.S with S.R content S.R (%) Resistivity curve Figure 7 Variation of Resistivity with S.R content Temperature curve Figure 8 Variation of Temperature rise with S.R content. CONCLUSION On the basis of results obtained, following conclusions are presented: S.R (%) By introducing S.R in concrete the flow of electronic current is observed. Initially the resistivity of concrete shows increase and the energy of flowing electrons is converted into heat which proves useful in De-iceing purposes. At 3% replacement of sand by S.R shows maximum Resistivity value and maximum heat or temperature rise. With further increase in steel residue a continuous conductive path is generated 72 editor@iaeme.com

8 Use of Waste Conductive Steel Residue In Concrete Proving Beneficial For De-Iceing of Pavements and the resistivity of concrete is decreased.thus, the concrete behaves as conductor than an insulator. Therefore, 3% replacement is the optimum value for the purpose. 3% replacement of fine aggregates by S.R showed 27% increase in compressive strength, 22.2% increase in compressive strength at 7 days and 8.5% increase in compressive strength at 28 days. Workability of concrete mix increases continuously with increase in S.R, as no water is absorbed by the steel residue. Use of S.R in concrete will eradicate its disposal problem and prove to be environment friendly thus paving way for greener concrete. Use of S.R in concrete will preserve natural resources particularly river sand and thus make concrete construction industry sustainable. REFERENCES [1] D.D.L. Chung, Data Sheet - Controlled Resistivity Alumina for Static Charge Dissipation, WESGO Technical Ceramics, Composite Materials, Vol. 22, No. 2 pp , 2001, Belmont, CA, USA. [2] M.A. Taylor, K. Arulanadan, Relationship Between Electrical and Physical Properties of Cement Pastes, Cement and Concrete Research, Vol. 4, No. 6, p. 881, [3] X. Zhang, X.Z. Ding, C.K. Ong, B.T.G. Tan, J. Yang, Dielectric and Electrical Properties of Ordinary Portland Cement and Slag Cement in the Early Hydration Period, Journal of Materials Sci., Vol. 31, Issue 5, pp , [4] N.M. Tabatabaei, S.R. Mortezaeei, Design of Grounding Systems in Substations by ETAP Intelligent Software, International Journal on Technical and Physical Problems of Engineering (IJTPE), Issue 2, Vol. 2, No. 1, pp , March [5] A.J. Ewins, Resistivity Measurements in Concrete, British Journal of NDT, Vol. 32, No. 3, p. 120, [6] A.M. Neville, Properties of Concrete - 4th Edition, Addison Wesley Longman, London, p. 844, [7] P.P. Xie, Y.F. Gu, J.S. Beaudoin, Determination of Blast-Furnace Slag Content in Hardened Concrete by Electrical Conductivity Methods, Cement, Concrete, and Aggregates, CCAGDP, Vol. 17, No. 1, pp.79-83, [8] 43 Grade Ordinary Portland cement Specification. IS 8112:1989, Bureau of Indian Standards, New Delhi. [9] Specification for Coarse and Fine Aggregates from Natural Sources for Concrete. IS: , Bureau of Indian Standards, New Delhi. [10] Recommended Guidelines for Concrete Mix Design. IS: , Bureau of Indian Standards, New Delhi. [11] Methods of Sampling and Analysis of Concrete. IS: , BIS, New Delhi. [12] Methods of Tests for Strength of Concrete. IS: , BIS, New Delhi. [13] A. Keyvani, M. Ahsanzadeh, M. Habibzadeh, Electrical Resistivity of Cement Paste in Reinforced Concrete Structures of Electrically Powered Transit Lines, The 3rd Conference on Technical and Physical Problems in Power Engineering (ICTPE-2006), Ankara, Turkey, May [14] Mohammed Yusuf Sagri, S.S.Kadam, Dr.C.P.Pise, Y. P. Pawar, D. D. Mohite and C. M. Deshmukh, To Investigate Combined Influence of Steel Fiber and Silicafume on High Strength Concrete Rigid Pavement. International Journal of Civil Engineering and Technology, 6(6), 2015, pp editor@iaeme.com