Experimental Study on Properties and Effects of Copper Slag in Self Compacting Concrete

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1 IJSTE - International Journal of Science Technology & Engineering Volume 2 Issue 12 June 2016 ISSN (online): X Experimental Study on Properties and Effects of Copper Slag in Self Compacting Concrete Rahul S PG Scholar Department of Structural Engineering Dr. T Senthil Vadivel Professor & Head of Dept. Department of Civil Engineering Rasl Muhammed Rafeeq PG Scholar Department of Structural Engineering Dr. S Kanchana Associate Professor Department of Civil Engineering Abstract Copper slag is the waste material obtained from smelting and refining of copper. Copper slag is one of the materials that is considered as a waste which could have a promising future in construction Industry as partial or full substitute of aggregates. For this research work, M25 grade concrete was used and tests were conducted for various proportions of copper slag replacement with sand of 0 to 50% in Self compacting concrete. Strength properties such as Compressive Strength, Split Tensile Strength, Flexural Strength, to be evaluated experimentally. The obtained results were compared with those of control SCC. The results indicate that the compressive strength, flexural strength and split tensile strength are increased up to 40% replacement of Copper Slag as Fine Aggregate in SCC. Addition of up to 50% of copper slag as sand replacement yielded comparable strength with that of the control mix. Further additions of copper slag caused reduction in the strength due to an increase of the free water content in the mix. Mixes with 80% and 100% copper slag replacement gave the lowest compressive strength. This research study was conducted to investigate the performance of copper slag in self- compacting concrete as partial replacement of fine aggregate. Therefore, it is recommended that 40% of copper slag can used as replacement of sand in order to obtain HPC with good strength and durability properties. Keywords: Self Compacting concrete, Copper Slag, Compressive strength, Flexural strength, Split tensile strength I. INTRODUCTION It was well recognized for many years the beneficial utilization of some industrial byproducts in improving the properties of fresh and hardened concrete. Use of some waste materials has been well documented in design specifications. New by-products and waste materials are being generated by various industries, dumping or disposal of these materials causes environmental and health problems. Therefore, recycling of waste materials a great potential in concrete industry. Concrete is one of the major construction material being used worldwide. Self-Compacting Concrete (SCC)) is a type of concrete that has the capacity to consolidate under its own weight. The usage of mineral admixtures in the production of SCC not only provides economic benefits but also reduces heat of hydration. These materials are also used to prevent segregation, bleeding, and increase flow ability. Copper Slag (CS) has excellent soundness characteristics, good abrasion resistance and good stability. Copper Slag has a lower water absorption capacity when compared with Sand. Copper Slag behaves similar to River Sand. Replacement of Copper Slag as Fine Aggregate in concrete mixes reduces the cost of concrete production. The use of copper slag in cement and concrete provides potential environmental as well as economic benefits for all related industries, particularly in areas where a considerable amount of copper slag is produced. Although copper slag is widely used in the sand blasting industry and in the manufacturing of abrasive tools, the remainder is disposed of without any further reuse or reclamation. Copper slag possesses mechanical and chemical characteristics that qualify the material to be used in concrete as a partial replacement for Portland cement or as a substitute for aggregates. Self-Compacting Concrete: Self-compacting concrete is an innovative concrete that does not require vibration for placing and compaction. It is able to flow under its own weight, completely filling formwork and achieving full compaction, even in the presence of congested reinforcement. The use of SCC in concrete structures increasingly has become prevalent in recent years. SCC offers many advantages for the precast, prestressed concrete industry and for cast-insitu construction. All rights reserved by 455

2 Materials: The materials used in the project should confirm certain properties which are given below. Cement: Experimental Study on Properties and Effects of Copper Slag in Self Compacting Concrete Cement is the well-known building material with adhesive and cohesive properties, which is capable of binding mineral fragment into compact mass. There are several types of cement. Ordinary Portland current 53 Grade with physical and chemical properties as give in table has been used in this experimental study. Table 1 Physical Properties of Ordinary Portland cement Physical Properties Result Fineness Modulus % 2 Specific gravity 3.13 Soundness (mm) 1.9 Initial Setting Time (min) 36 Final setting time (min) 300 Fine Aggregate: Aggregate which is passed through 4.75 mm IS sieve and retained on 75 microns IS sieve is termed as fine aggregate. It fills the voids in coarse aggregate. Usually, the natural river sand is used as fine aggregate. Ordinary river sand conforming IS is used in this project. Locally available river sand conforming to grading Zone II is used in this experimental work. Table - 2 Physical Properties of Fine Aggregate Properties Result Specific gravity 2.74 Fineness modulus % 3.16 Water absorption % 0.7 Coarse Aggregate: Aggregate which passes through 75 mm IS sieve and retained on 4.75 mm IS sieve are known as coarse aggregate. Aggregates should be properly screened and if necessary washed before use. Coarse aggregates containing flat, elongated or flaky pieces should be rejected. Locally available crushed stones conforming to graded aggregate of normal size 10 mm as per IS: is used in this experimental work. Table 3 Physical Properties of Coarse Aggregate Properties Result Properties 2.69 Fineness modulus % 6.34 Water absorption % 1.5 Copper Slag: Copper slag is a by-product obtained during matte smelting and refining of copper. The slag is a black glassy particle and granular in nature and has a similar particle size range like sand. It has good pozzalonic properties. The copper slag was brought from Blastline Industries Ltd (BIL), Kochi, Ernakulam, India. Table 4 Physical Properties of Copper Slag Properties Result Specific gravity 3.37 Fineness modulus % 4.13 Water absorption % 0.14 Table 5 Chemical Properties of Copper Slag SL. No Chemical Component % of Chemical Component 1 SiO Fe2O Al2O CaO Na2O K2O Loss on Ignition 6.59 All rights reserved by 456

3 Water: Experimental Study on Properties and Effects of Copper Slag in Self Compacting Concrete 8 Mn2O TiO SO CuO Sulphide sulphur Insoluble residue Water used for mixing and curing shall be clean and free from oils, acids, alkalis, salts etc. Water used for the study was free of acids, organic matter, suspended solids, alkalis and impurities when present may have adverse effect on the strength of concrete. Portable water with Ph value 7 conforming to IS: was used for making concrete and curing this specimen as well. II. MIX PROPORTIONS A total of 6 concrete mixtures were designed as per IS having a constant water- cement ratio of The control mixture of grade M25 included ordinary Portland cement alone as the binder and Copper Slag as Partial replacement for Fine Aggregate. The replacement levels of Copper Slag as Fine Aggregate are in the percentages 0%, 10%, 20%, 30% and 40%, 50% respectively. III. EXPERIMENTAL INVESTIGATION The research programme involved in the replacement of fine aggregate with the abundantly available waste material such as copper slag. For the work 36 cubes, 18 cylinder and 18 prism specimens were casted and tested for the required properties. Fresh Concrete Properties: Slump Test: The Slump flow is used to evaluate the horizontal free flow of SCC in the absence of obstructions. The slump cone was filled with concrete and the top of cone was struck off with a trowel. The mould was removed from the concrete immediately by raising it slowly and carefully in a vertical direction. Concrete allowed to flow in horizontal direction. The diameter of the spread concrete was measured in two perpendicular directions and recorded as slump flow. The test has been conducted for all the various mix. The samples were tested and the results were shown in the Fig. 1 Hardened Concrete Properties: Fig. 1: Slump Flow Value for Different Percentages Compressive Strength: The compressive strength test for cubes was conducted in compression testing machine at the rate of 140 kg/cm 2 /min as per IS 516: 1964 and the ultimate loads were recorded. The result of compressive strength of cubes for 7 and 28 days curing are shown in Table 6. It can also be seen that the compressive strength of concrete increases with an increase in replacement percentage of Copper Slag up to 50% addition. The bearing surface of machine was wiped off clean and the surface of the specimen was cleaned. The specimen was placed in machine and the axis of the specimen was carefully aligned at the center of loading frame. All rights reserved by 457

4 Experimental Study on Properties and Effects of Copper Slag in Self Compacting Concrete Table 6 Compressive Strength of Cubes sdqg Compressive Strength at 7 th day (N/mm 2 ) Compressive Strength at 28 th day (N/mm 2 ) SCC CS10% CS20% CS30% CS40% CS50% Fig. 2: Characteristic Compressive strength for various replacement of Copper Slag Fig 2 shows the graphical representation of variation of compressive strength of cubes at 7 th and 28 th day. The average compressive strength of the samples is taken as compressive strength of corresponding concrete grade. It is observed that compressive strength of concrete increases with the percentage replacement of copper slag when compared with control mix (SCC). The compressive strength increased up to 16% at 40% replacement. After 50% replacement the compressive strength decreases but higher than that of conventional concrete. Split Tensile Strength: The split tensile strength test for cylinders was carried out as per IS 516: The Universal testing machine was used for this test. The cylinder specimen was placed horizontally between the loading surfaces and the load was applied continuously up to the specimen get failed. The failure load of the specimen was recorded in table 7. Table 7 Split Tensile strength of concrete Specimen Split Tensile Strength (N/mm 2 ) Description Specimen 1 Specimen 2 Specimen 3 Average SCC CS10% CS20% CS30% CS40% CS50% All rights reserved by 458

5 Experimental Study on Properties and Effects of Copper Slag in Self Compacting Concrete Fig. 3: Split Tensile strength for various replacement of Fine aggregate with Copper slag The graphical representation of the variation of average split tensile strength at 28 th day is shown in fig3. It is observed that Split Tensile strength of concrete increases with the percentage replacement of copper slag when compared with control mix (SCC). From the split tensile strength test it was observed that there was an increase in strength by 51% at 40% replacement of CS when compared with control mix. Flexural Strength: The flexural strength is the ability of a beam or slab to resist failure in bending. Flexural test can be carried on the flexural testing machine. The specimen was placed on the machine and the load was applied on the upper most surface in such a way that the axis of the specimen was carefully aligned with the loading device. The rate of loading was about 400kg/min. The failure load was recorded and tabulated. Table 8 Flexural strength of cement replacement with blended concrete Specimen Flexural strength (N/mm 2 ) Description Specimen 1 Specimen 2 Specimen 3 Average SCC CS10% CS20% CS30% CS40% CS50% Fig. 4: Flexural strength for various replacement of Fine aggregate with Copper slag All rights reserved by 459

6 Experimental Study on Properties and Effects of Copper Slag in Self Compacting Concrete The graphical representation of the variation of average flexural strength at 28 th day is shown in fig 4. The flexural strength test was conducted on prism subjected to two points loading and it is observed that the highest flexural strength is reached up to 40% replacement. The flexural strength was increased by 15% at 40% replacement of CS when compared with control mix. So this mix was taken as the optimized mix. IV. RESULT AND DISCUSSION The replacement of Copper Slag as fine aggregate in Self Compacting Concrete is studied and the following conclusions have been achieved in this experimental study. As the percentage of CS increases workability increases. The slump value increases in all samples compared to conventional SCC as the percentage of copper slag increases. The strength of concrete increases with the percentage replacement of copper slag. Compared to conventional SCC the compressive strength increased by 16%, Split tensile strength by 51 % and Flexural strength by 15% more. The strength of concrete is increased due to the high toughness of CS. After the limit is reached, the strength decreases because there is not enough paste to coat the aggregate. It is recommended that up to 40% of CS can be used as replacement of FA in SCC. V. CONCLUSION Up to 40% of replacement of Copper Slag in Self Compacting Concrete the Compressive Strength, Split Tensile Strength and Flexural Strength of concrete is increased compared to conventional concrete. The optimum value obtained for 40% replacement of CS as fine aggregate in concrete. The strength of concrete is increased due to the high toughness of CS. It is also concluded that the CS performs similar or better compared to natural sand concrete. REFERENCES [1] Binaya Patnaik A, Seshadri Sekhar T.A and Srinivasa Rao B, An Experimental Investigation on Optimum Usage of Copper Slag as Fine Aggregate in Copper Slag Admixed Concrete International journal of current engineering and technology. [2] Johnsirani K.S, Jagannathan, Dinesh Kumar R,(2013), Experimental investigation of Self- compacting concrete using quarry dust, International Journal of Scientific and Research Publications, Volume 3. [3] Dhiyaneshwaran S, Ramanatha, P, Baskar I) and Venkatasubramani R, Study on Durability Characteristics of Self-Compacting Concrete with Fly Ash, Jordan Journal of Civil Engineering, Volume 7 [4] Patil M.V (2015), a study on properties and effects of copper slag in concrete International journal of civil and structural engineering. [5] Pai B.H.V, Nandy S, Krishnamoorthy A, Sarkar P.K, Pramukh Ganapathy C (2014), Experimental study on self-compacting concrete containing industrial by-products European Scientific Journal, vol.10, No.12 ISSN: [6] Rahul Dubey, Pardeep Kumar (2012) Effect of superplasticizer dosages on compressive strength of Self compacting concrete, International Journal of Civil and Structural Engineering, Volume 3, No 2. [7] Hemant Sood, Khitoliya R.K and Pathak S. S,(2009), Incorporating European Standards for Testing Self Compacting Concrete in Indian Conditions, International Journal of Recent Trends in Engineering, Vol. 1, No. 6. All rights reserved by 460