STRENGTH PROPERTIES OF CONCRETE BY THE UTILISATION OF COPPER SLAG AS A PARTIAL REPLACEMENT OF FINE AGGREGATES

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1 STRENGTH PROPERTIES OF CONCRETE BY THE UTILISATION OF COPPER SLAG AS A PARTIAL REPLACEMENT OF FINE AGGREGATES JAKKAMSETTI INDIRA PRIYADARSINI 1, SRI DUMPA VENKATESWARLU 2 1 M. Tech (Structural Engineering), Department of Civil Engineering, GIET Institute of Engineering and Technology, NH -16, Chaitanya Knowledge City, Rajahmundry, A.P., India. 2 Professor (M.Tech.., PH.D..,) Department of Civil Engineering, GIET Institute of Engineering and Technology, NH -16, Chaitanya Knowledge City, Rajahmundry, A.P., India. ABSRACT: Concrete is always expected to be stronger and more durable in the past while being cost and energy efficient. Moreover the major advantages that concrete possesses over the construction materials have to be conserved. The possibility of being fabricated practically anywhere, the ability to make the form imposed by the shape of a mould and a low cost of components and manufacture. These factors have driven advances in improving the performance of concrete over years and continue to do so the need for improving the performance of concrete and concern for the environmental impact arising from the continually increasing demand for concrete has lead the growing use of alternative material components. An experimental investigation will be conducted to study the properties of concrete containing copper slag as a partial replacement of fine aggregates in the concrete mix design. Various durability tests will be conducted on such concrete of M40 and M50 grades to know the compressive strength, split tensile strength, flexural strength by varying proportions of copper slag with fine aggregates by 0%, 10%, 20%, 30%, 40% and 50% by weight. The obtained results will be compared with the conventional concrete, there by knowing the changes in the properties of concrete containing copper slag as a partial replacement of fine aggregates. I INTRODUCTION Concrete is a widely used construction material for various types of structures due to its durability. The use of concrete is unavoidable, at the same time the scarcity of aggregates is also increasing now-a-days. Natural resources are depleting worldwide at the same time the generated wastes from the industries increasing substantially. Utilization of industrial solid waste or secondary materials has been encouraged in construction field for the production of cement and concrete because it contributes to reducing the consumption of natural resources. For many years by products such as fly ash, silica fume, and slag were considered as waste material. They have been successfully used in the construction field for partial or full replacement of fine aggregates and coarse aggregates. Hence by the utilization of copper slag which has low cost and its application as a replacement of fine aggregate in concrete production have many environmental benefits such as waste recycling and solve disposal problems. Copper slag is a by-product obtained during the smelting and refining process in extracting copper

2 metal from its ore. Copper slag is the one of the materials that is considered as a waste material and industrial passive material which could have been used in construction industry as partial replacement of fine aggregates in mixed design. Approximately about 2.2 tons of waste slag is generated for every 1 ton of metal production. Copper slag is a glassy granular material with high specific gravity. Particle sizes are of the order of sand and have a potential for the use as fine aggregate in concrete. Uses of Copper Slag: 1. Copper slag has also gained popularity in the building industry for use as a fill material. 2. Contractors may also use copper slag in place of sand during concrete construction. 3. Copper slag can also be used as a building material, formed into blocks. 4. Copper slag is widely used in the sand blasting industry and it has been used in the manufacture of abrasive tools. Due to highly durable nature of concrete low maintenance is required. 5. Copper slag is widely used as an abrasive media to remove rust, old coating and other impurities in dry abrasive blasting due to its high hardness (6-7 Mohs), high density ( g/cm) and low free silica content. Properties of Copper Slag: 1. Copper slag (CS), the glassy material, produced during matte smelting and copper conversion was previously considered waste and disposed as landfill. It has been estimated that for every ton of copper production about tons of slag are generated. 2. Copper slag, a copper production residue, shows in its chemical composition high contents of aluminium, silica and iron oxides, similar to that of cement. 3. Additionally, its hardness and gradation seems to indicate its suitability for use as alternative aggregate for applications in construction products. 4. Aggregate is the main constituent of concrete, occupying more than 70% of the concrete matrix. Slag containing < 0.8% copper are either discarded as waste or sold cheaply. 5. Copper slag is similar to sand in grading and its hard, non-absorptive, nonreactive properties make it an ideal fine filler material for concrete after it is suitably washed to remove all impurities. II LITERATURE REVIEW Al-Jabri et al (2009) states that the performance of high strength concrete (HSC) made with copper slag as a fine aggregate at constant workability and studied the effect of super plasticizer addition on the properties of HSC made with copper slag. Two series of concrete mixtures were prepared with different proportions of copper slag. The first series consisted of six concrete mixtures prepared with different proportions of copper slag at constant workability. The water content was adjusted in each mixture in order to achieve the same workability as that of the control mixture. Wei wu et al (2010) states that the mechanical properties of high strength concrete incorporating copper slag as fine aggregate. The workability and strength characteristics were assessed through a series of tests on six different mixing proportions at 20% incremental copper slag by weight replacement

3 of sand from 0% to 100%. A high range water reducing admixture was incorporated to achieve adequate workability. Micro silica with a specific gravity of 2.0 was used to supplement the cementitious content in the mix for high strength requirement. Bipra gorai et al (2003) states that the characteristics of copper slag as well as various processes such as pyro, hydro and combination of pyro hydro metallurgical methods for metal recovery and preparation of value added products from copper slag. Copper slag, which is produced during pyro metallurgical production of copper from copper ores, contains materials like iron, alumina, calcium oxide, silica etc. EXPERIMENTAL INVESTIGATION To achieve the objectives discussed earlier, experimental program is planned to study the effect of replacement of fine aggregate by copper slag on strength properties of concrete. Scheme of experimental program: MATERIAL USED: Cement: The ordinary Portland cement of 53 grade is used in accordance with IS: Properties of this cement were tested and listed here. 1. Fineness of cement = 5% 2. Specific gravity if cement = Standard Consistency of cement = 33% 4. Initial setting time = 50 minutes 5. Final setting time = Not more than 10 hours. Aggregates: Coarse aggregate: Crushed stone aggregate of 20mm size is brought from nearby quarry. Aggregates of size more than 20mm size are separated by sieving. Tests are carried in order to find out the Specific gravity = 2.98 Fineness modulus = 7.5 The details of number of blocks to be tested while the experimentation process is given in the below table: Number of blocks required for the experiment Coarse aggregate Fine aggregate: Locally available fresh sand, free from organic matter is used. The result of sieve analysis confirms it to Zone-II (according to IS: ).The tests conducted and results plotted below. In each batch 3 cubes, 3 cylinders and 3 prisms were casted. Totally 36 cubes, 36 cylinders and 36 prisms were casted during entire experimentation. Specific gravity = 2.3 Fineness modulus = 3.06

4 Copper slag: The copper slag which we used had collected from a dealer of 'Hindustan copper limited' at Vishakhapatnam. The wholesale price of the copper slag is about 650/ton and is also economical to use copper slag at the places where it is available. The tests and results of copper slag are as follows. Specific gravity = 3.56 Fineness modulus = 4.55 TESTS TO BE CONDUCTED : Compressive Strength Test: Copper slag Water: Generally potable water should be used. This is to ensure that the water is reasonable free from such impurities as suspended solids, organic matter and dissolved salts, which may adversely affect the properties of the concrete, especially the setting, hardening, strength, durability, pit value, etc. This test was conducted as per IS The cubes of standard size 150x150x150mm were used to find the compressive strength of concrete. Specimens were placed on the bearing surface of CTM, of capacity 200T without eccentricity and a uniform rate of loading applied till the failure of the cube. The maximum load was noted and the compressive strength was calculated. MIX DESIGN AND QUANTITY OF MATERIALS Based on the values obtained from above tests a mix proportioning design for the concrete of M40 and M50 grades is done using IS code method. Casting of cubes For M40 grade mix design is 1:1.49:2.12 and w/c is 0.4 For M50 grade mix design is 1:1.34:2 and w/c is 0.35 Compressive strength testing procedure from IS :

5 Compressive strength testing machine The load shall applied without shock and increased continuously at a rate of approximately 140kg/cm2/min until the resistance of the specimen to be increasing load breaks down and no greater load can be sustained. The maximum load applied to the specimen shall then be recorded and appearance of the concrete and any unusual features in the type of failure shall be noted. Flexural strength test: Split Tensile Strength Testing Flexural strength testing procedure from IS : The compressive strength of cube = (P/A) N/mm2 Where, P is load at failure in N, A is area of cube/contact in mm2. Split Tensile Strength Test: This test was conducted as per IS The cylinders of standard size 150mmx300mm were used find the strength of concrete The load shall be applied without shock and increased continuously at a nominal rate within in the range 1.2 N/mm/min to 2.4N/mm/min. The split tensile strength = (2P/πdl) N/mm2 Where, P= average load in N, d=diameter of cylinder in mm, l=length of cylinder in mm. Testing Square prism for flexural strength The load shall be applied without shock and increasing continuously at a rate such that extreme fiber stress increases approximately 7kg/cm2 that is at the rate of loading of 400kg/min for the 15cm specimens and the rate of 180kg/min for 10cm specimen. The load shall be increased until specimen fails, and the maximum load to the specimen during the test shall be recorded. fb= (Pl/bd2) N/mm2 Where, b= measured width in cm of specimen, d= measured depth in cm of specimen at a point of failure, l= length in cm of the span on which the specimen was supported, P= maximum load in kg applied to specimen.

6 TEST RESULTS Flexural strength of concrete: Compressive strength of concrete: Graph: Graph; CONCLUSIONS Split Tensile strength of concrete: Graph: Compressive strength of concrete constantly increases up to 40% Copper Slag (CS) replacement with Fine aggregate but further decreases if the %CS replacement increases. When compared no nominal concrete the compressive strength of concrete increased by a maximum of 12% for M40 grade and 12% for M50 grade at 40% CS replacement. Flexural strength of concrete constantly increases up to 40% CS replacement with Fine aggregate but further decreases if the %CS replacement increases. When compared no nominal concrete the flexural strength of concrete increased by a maximum of 12% for M40 grade and 9% for M50 grade at 40% CS replacement.

7 Split Tensile strength of concrete constantly increases up to 40% CS replacement with Fine aggregate but further decreases if the %CS replacement increases. When compared no nominal concrete the compressive strength of concrete increased by a maximum of11% for M40 grade and 13% for M50 grade at 40% CS replacement It is concluded that the concrete, at an optimum of 40% CS replacement with fine aggregates can achieve desirable higher strengths than that of nominal concrete. The minimum strength required for M40 and M50 grades of concrete is achieved by utilizing CS up to 50% replacement with Fine aggregates. FUTURE RECOMMENDATIONS: [1] Using Copper Slag up to 100% replacement with Fine aggregates and checking out whether the minimum strength required for M40 and M50 grades of concrete can be achieved. [2] Checking out the feasibility of utilization of Copper slag as Coarse aggregates and finding the Strength characteristics of Concrete. REFERENCES [1] Brindha, D and Nagan, S (2010). Utilization of copper slag as a partial replacement of fine aggregate. International Journal of Earth Sciences and Engineering,Vol.3, No.4, pp [2] Wei Wu, Weide Zhang, Guowei Ma Optimum content of copper slag as a fine aggregate in high strength concrete Materials and Design, Elsevier science Ltd, Vol. 31, 2010, pp [3] Pazhani K, Jeyaraj R, Study on durability of high performance concrete with industrial wastes, Peerreviewed & Open access journal, ATI- Applied Technologies & Innovations, Vol. 2, Issue 2, August 2010, pp [4] Khalifa S Al-Jabri, Abdullah H Al-Saidy, Ramzi Taha, Effect of copper slag as a fine aggregate on the properties of cement mortars and concrete, Construction and Building Materials, Vol. 25, 2011, pp [5] Mostafa Khanzadi, Ali Beholds(2009), Mechanical properties of high strength concrete incorporating copper slag as coarse aggregate, Construction and Building Materials 23 pp [6] Meenakshi Sudarvizhi, S. and Ilangovan, R. Performance of copper slag and ferrous slag as partial replacement of sand in concrete, International Journal of Civil and Structural Engineering, Vol.1, No.4, [7] Chavan, R.R. and Kulkarni, D.B. Performance of copper slag on strength properties as partial replacement of fine aggregate in concrete mix design, International Journal of Advanced Research and Studies, Vol.2, No.4, pp.95-98, [8] IS: , Concrete Mix Proportioning, Bureau of Indian Standards, New Delhi. IS 516 (1959): Method of Tests for Strength of Concrete [CED 2: Cement and Concrete]