INFLUENCE OF STEEL SHOTS IN ACHIEVING HIGH DENSITY CONCRETE

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 13, December 2018, pp , Article ID: IJCIET_09_13_173 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed INFLUENCE OF STEEL SHOTS IN ACHIEVING HIGH DENSITY CONCRETE Anandu Sreeraj, Arunroy.N.S, Noel Francis and Mathew paul Students, Schools of Mechanical and Building Science, VIT, Chennai, Tamil Nadu, India. Dr.V Vasugi Associate Professor, Schools of Mechanical and Building Science, VIT, Chennai, Tamil Nadu, India. ABSTRACT A concrete having density greater than 2800kg/m 3 can be considered as a high density concrete. They are widely used in nuclear power plants, railways, foundations (as stabilizers), crane counter weights etc. This experimental study aims to increase the density of concrete by replacing the fine aggregates partially with steel shots. In this study, M35 mix was used where, 50% of fine aggregates was replaced with steel shots. The physical and mechanical properties like density, compressive strength, tensile strength and non-destructive tests such as rebound hammer and ultrasonic pulse velocity tests were done for both 7 and 28 days. A concrete having density of 3183kg/m 3 was achieved from this study. Key words: High density concrete, steel shots, physical and mechanical properties, ndt; Cite this Article: Anandu Sreeraj, Arunroy.N.S, Noel Francis, Mathew paul and Dr.V Vasugi, Influence of Steel Shots in Achieving High Density Concrete, International Journal of Civil Engineering and Technology, 9(13), 2018, pp INTRODUCTION The rapid growth in construction industry has triggered the need for research in different varieties of concrete for satisfying various requirements according to our industrial needs. One such variety of concrete having very high industrial demand is High density concrete. Conventional concrete has a density of around 2400kg/m 3. A high density concrete can be achieved if the density of concrete is above 2800kg/m 3. The different materials used for achieving high density concrete are steel punching, Iron, Barite, etc [1, 2, 3, 4, 5, 6, 7]. İlker Bekir studied the influence of w/c ratio in heavy weight concrete and found that decrease in editor@iaeme.com

2 Anandu Sreeraj, Arunroy.N.S, Noel Francis, Mathew paul and Dr.V Vasugi w/c ratio increases compressive strength while increase in w/c ratio decreases unit weight of concrete [1]. The compressive strength of the high density is found to be more than the conventional concrete due to the high bonding between the aggregate and cement [1-7]. High density concrete has high resistance towards the radiation, hence it is used in nuclear power plants for protection from the radiation emitted during the nuclear process. It helps in reducing the thickness of walls used for radiation shielding [4, 6, 7]. High density concrete also shows good results to all the engineering properties such as compressive strength, tensile strength, and flexural strength [3, 5]. 2. EXPERIMENTAL STUDIES 2.1. Materials For preparing high density concrete mix, Ordinary Portland cement was used. The fine aggregate used was M sand having a specific gravity of Coarse aggregates of 20 mm size having a specific gravity of 2.74 was used. Steel shots (Figure 1) having 1.73 mm diameter with 7.8 specific gravity was used in partial replacement of fine aggregate. Polycarboxylate Ether was used as super plasticizer. Figure 1. Steel shots 2.2. Mix proportion The mix design as per the Indian standard specifications [8] for M35 mix was done. The mix proportion attained after doing several trail mixes was 1:1.9:3.5. From the mix proportion, 50% volume of the fine aggregate was replaced with steel shots. The quantity of materials used for the test is shown in the Table 1. Table 1. Quantity of materials Materials Cement Water Super plasticizer Coarse aggregate (20mm) Fine aggregate (M sand) Steel shot Quantity 27kg 10liters 10ml 96kg 26kg 73kg editor@iaeme.com

3 Influence of Steel Shots in Achieving High Density Concrete 2.3. Preparation of specimens Fresh concrete properties Fresh concrete properties helps to ensure the uniformity, consistency and resistance against the deterioration. The fresh properties of concrete are shown in Table 2. Table 2. Concrete fresh property Sl.No 1 Test Slump test Min value to be obtained Above than 75 mm according to IS 7320: Density >2800kg/ m 3 Parameter Consistency High density concrete Preparations of specimens and curing conditions Six cubes of 150mm x150mm x 150mm size, six cylinders 100mm diameter and 200mm height and six beams of 100mm x 100mm x 700 mm were casted and cured in fresh water tank. Number of specimens used for finding the engineering properties of concrete is given in the Table 3. Table 3. Number of specimens for engineering properties Days 7 days 28 days Tests No. of samples No. of samples Compressive strength 3 Cubes 3 Cubes Tensile strength 3 cylinders 3 cylinders Flexural strength 3. RESULTS AND DISSCUSSIONS 3.1. Test on fresh concrete 3 beams 3 beams Slump test True slump was obtained with a slump value of 28 mm. The mix was having low workability Density test A density of kg/m 3 was obtained for the fresh concrete, mixed by replacing 50% of fine aggregate with steel shots editor@iaeme.com

4 Anandu Sreeraj, Arunroy.N.S, Noel Francis, Mathew paul and Dr.V Vasugi 3.2. Engineering properties Compressive strength test Figure 2. Compressive strength of cubes By replacing 50% of fine aggregate by steel shots, the concrete attained more than 90% of strength in 7 days. The compressive strengths of concrete on 7 th and 28 th days are 32.53N/mm 2 and N/mm 2 (Figure 2) Split tensile strength test Figure 3. Split tensile strength of cylinder Concrete is usually strong in compression but weak in tension. The split tensile strength of concrete for 7 th and 28 th days were 2.35 N/mm 2 and 3.35 N/mm 2 respectively (Figure 3) Flexural strength test Figure 4. Flexural strength test editor@iaeme.com

5 Influence of Steel Shots in Achieving High Density Concrete Flexural strength of concrete is the resistance of beam or slab against failure in bending. The flexural strength of concrete after 7 th and 28 th days were N/mm 2 and N/mm 2 respectively (Figure 4) Ultrasonic pulse velocity test Figure 5. Ultrasonic pulse velocity The ultrasonic pulse velocity test determines the strength and quality of concrete by determining the velocity of ultrasonic pulses passing through specimen. The velocities of pulses obtained after 7 th and 28 th days were 4.43Km/s and 4.29 Km/s respectively (Figure 5). According to the specifications given by IS , the concrete produced are having very good quality and uniformity Rebound hammer test Figure 6. Rebound number The rebound hammer test helps in determining hardness of a specimen. Rebound number obtained for 7 th and 28 th days were 31 and 36 corresponding to a compressive strength of 28 N/mm 2 and 35 N/mm 2 respectively (Figure 6) editor@iaeme.com

6 Anandu Sreeraj, Arunroy.N.S, Noel Francis, Mathew paul and Dr.V Vasugi 4. CONCLUSIONS The following conclusions were derived from the results: High density concrete was achieved by replacing 50% of fine aggregate with steel shots. A density of kg/m 3 was obtained for hardened concrete, which is well above the density of regular concrete. Compressive strength greater than the target strength was achieved. Quality of concrete was found to be very good from ultrasonic pulse velocity test. High density concrete helps in minimizing the quantity of raw materials since it reduces overall thickness of the structural member. REFERENCES [1] İlker Bekir Topc u. Properties of heavyweight concrete produced with barite. Cement and concrete research; ( ). [2] S. Kilincarslan, I. Akkurt, C. Basyigit. The effect of barite rate on some physical and mechanical properties of concrete. Materials Science and Engineering; A [3] Zainab Z. Ismail, Enas A. AL-Hashmi Reuse of waste iron as a partial replacement of sand in concrete. Waste Management; Volume 28, Issue 11, Pages [4] SMJ Mortazavi, M.A. Mosleh-Shirazi, M.R. Maheri, H. Yousefnia, S. Zolghadri, A. Hajipour. Production of an economic high-density concrete for shielding megavoltage radiotherapy rooms and nuclear reactors. Iranian journal of radiation research; Volume 5(3) page [5] Viktors Mironovs, Jānis Broņka, Aleksandrs Korjakins, Jānis Kazjonovs.. Possibilities of application Iron containing waste materials in manufacturing of Heavy Concrete. International conference building materials; Volume 11. [6] Ahmed S. Ouda. Development of high performance heavy density concrete using different aggregates for gamma-ray shielding. Housing and Building national research center journal; Volume 11 page [7] Sivathanu Pillai C., Santhakumar A.R., Chandrasekaran S., Viswanathan S., Mathiyarasu R., Kumar J. Ashok, Preetha R., Venkatraman B. Effect of heat treatment on neutron attenuation characteristics of high density concretes (HDC). Progress in Nuclear Energy; , [8] IS 10262: 2009: Concrete mix proportioning guidelines. [9] IS : Method of Non- destructive testing of concrete, Ultrasonic pulse velocity. [10] IS : Method of Non destructive testing of concrete, Rebound hammer editor@iaeme.com