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Second International Conference on Recent Advances in Science & Engineering-2015 Experimental Study on Glass Fiber Reinforced Concrete with Steel Slag and M-Sand as Replacement of Natural Aggregates Anil Kumar M M.Tech Scholar Vijaya Vittala Institute of Technology Bangalore Prof. Virendra Kumar K N Civil Engineering Department Vijaya Vittala Institute of Technology Bangalore ABSTRACT The use of Glass Fiber Reinforced Concrete (GFRC) has been increasing due to rapid growth of urbanization. But, due to increase in use of conventional materials for GFRC has increased the cost of production and also has negative impact on environment due to excessive mining and use of these materials for the production of GFRC. In the present work, an experimental study was made to assess the suitability of Fly Ash, Steel Slag and M-Sand as replacement for cement, coarse aggregate and river sand respectively. Mix design for M60 grade was done using 0.2% of glass fibers. Steel Slag and M-Sand were added as replacement in 25%, 50%, 75% and 100% to determine the optimum replacement level; also cement was replaced with fly ash by constant 30% for all variations. Strength and durability tests were conducted for 7, 14 and 28 days. Experimental study showed that replacement level of 75% gave satisfactory results when compared with conventional concrete. Keywords—Glass Fibers, Fly ash, Steel Slag, M-Sand I. INTRODUCTION Concrete is the most widely used material in construction industry. Concrete with high strength along with long term durability, serviceability are the need of the day. Glass Fiber Reinforced Concrete consists of hydraulic Portland cement, coarse and fine aggregates along with alkali resistant glass fiber as reinforcement material. Natural aggregates are preferred for concrete but excessive mining of natural aggregates has caused environmental degradation. So, search for alternative to natural aggregates has already begun. Steel Slag a byproduct obtained from steel manufacturing industry can be used as coarse aggregate replacement. M-Sand a byproduction obtained from crushed rock during aggregate production can be used as fine aggregate replacement. Also fly ash which has cementitious property obtained from thermal power plant can be used for replacement of cement in concrete up to certain extent. Experimental studies of previous researchers have shown that addition of glass fibers enhances strength and durability of concrete. II. Previous Works Steel Slag as partial replacement of coarse aggregate was experimentally studied [1] and found that steel slag can be replaced 100% without reduction of strength of concrete. Concrete with steel slag as coarse aggregate replacement and eco sand as fine aggregate replacement was studied [2], which indicated that steel slag can be replaced up to 60% and eco sand can be replaced up to 40% without any adverse effect on the strength of concrete. Crushed rock powder as replacement of fine aggregate in concrete was experimentally evaluated [3], results showed that crushed rock powder can be replaced up to 40% without reduction in strength properties. Use of m-sand as fine aggregate replacement in concrete was studied [4], and results indicated that m-sand can be replaced up to 50% also reducing the cost of fine aggregate for the production of concrete. Fine aggregate replacement by crushed stone dust was experimentally carried out [5], and results showed that crushed stone sand can be effectively replace natural sand in concrete. Glass Fiber Reinforced Concrete and its properties was studied [6], and found that alkali resistant glass fiber used in concrete showed increase in strength properties than normal concrete. Suitability of steel slag as coarse and fine aggregate replacement was experimentally studied [7], and results showed that steel slag up to 100% replacement had no adverse effect on strength of concrete. Very few literatures are available regard to the use of steel slag and m-sand combined. The present study examines the possibility of using steel slag and m-sand as partial/full replacement of coarse and 1 © ISRASE 2015 ISRASE eXplore Digital Library Second International Conference on Recent Advances in Science & Engineering-2015 fine aggregate respectively. Also fly ash as replacement of cement by constant 30% for all variations with 0.2% of glass fibers as reinforcement material. III. Materials Used A. Cement The cement used was ordinary Portland cement of 53 grade with specific gravity of 3.14. The initial and final setting time of cement was 46 minutes and 192 minutes respectively. B. Fly ash In this study, fly ash is used as replacement of cement by constant 30% for all variations and is collected from Raichur Thermal Power Station, Karnataka. It has specific gravity of 2.1 and normal consistency of 31%. C. Coarse aggregate and Steel Slag The coarse aggregate of 20mm and below size were used in study. Steel Slag is obtained from JSW, Bellary for the present study. Table 1: Properties of Coarse aggregate and Steel Slag Particular Shape Bulk density of compacted aggregate Bulk density of loose aggregate Specific Gravity Water absorption Coarse Aggregate Angular 1562 kg/m3 1368 kg/m3 2.67 0.2% Steel Slag Angular 1628 kg/m3 1452 kg/m3 3.34 1.5% D. River Sand and M-Sand The river sand and m-sand used in the present study conforms to IS: 2368-1968. The m-sand was supplied by Bharathi Cements, Bangalore. Table 2: Properties of River Sand and M-Sand Particular Bulk density of loose sand Bulk density of compacted sand Specific Gravity Water Absorption Zone River Sand 1428 kg/m3 1624 kg/m3 2.62 0.9% II M-Sand 1898 kg/m3 1645 kg/m3 2.61 3.6% II E. Fibers Used In the present work, Cem-Fil anti crack glass fibers of length 12mm and aspect ratio 58 is used. F. Water Ordinary potable water was used for mixing and curing purpose. G. Super-plasticizer and Mix Proportion Glenium 8233 is used for the work. The percentage of super-plasticizer is 0.6% of total cementitious quantity. Table 3: Mix Proportion of M60 grade concrete Material Cement Fly Ash River Sand Coarse Aggregate Water Quantity 379.53 kg/m3 162.65 kg/m3 616.06 kg/m3 1115.8 kg/m3 159.27 kg/m3 2 © ISRASE 2015 ISRASE eXplore Digital Library Second International Conference on Recent Advances in Science & Engineering-2015 IV. Methodology A. Compressive Srength Test The compressive strength test was carried out on cube specimens of 150 x 150 x 150 mm size prepared in accordance with I.S: 516-1959 at 7,14 and 28 days using compression testing machine. The details of the six different specimens are as given in Table 4. Table 4: Details of Test Specimens Fine Aggregate (%) Mix Designation Cement + Fly Ash (%) River Sand M-Sand CC A0 A25 A50 A75 A100 100+0 70+30 70+30 70+30 70+30 70+30 100 100 75 50 25 - 25 50 75 100 Coarse Aggregate (%) Natural Coarse Steel Slag Aggregate 100 100 75 25 50 50 25 75 100 % of Glass Fiber by volume of concrete 0.2 0.2 0.2 0.2 0.2 B. Split Tensile Strength Test Cylinder specimens of 150mm diameter and 300 mm length were cast and placed horizontally in compression testing machine with wooden plates at the top and bottom. The split tensile test was conducted after curing periods of 7, 14 and 28 days. The load was applied at the top without shock and increased continuously at a rate within the range 1.2 N/mm2/minute to 2.4 N/mm2/minute until the failure of specimen. C. Water Absorption Test Concrete cube specimens of size 150 x 150 x 150 mm size were cast and test was conducted after curing period of 28 days. Then, the specimens were taken out from water and oven dried for 24 hours at constant 105 oC. The oven dried weight was taken and immersed again in water, the weight was recorded at regular intervals, till the weight becomes fully saturated. Then, the saturated weight is noted down. The difference between saturated weight and oven dried weight gives the water absorption of the specimens. V. Results and Discussions A. Compressive Strength of GFRC The values of compressive strength of all variations are given in Table 5. Fig 1 shows the variation of compressive strength in MPa with different curing periods for all variations used. It is seen from the test results that the compressive strength of GFRC at 7, 14 and 28 days increases initially as the percentage of replacement of steel slag and m-sand increases and becomes maximum at a percentage around 75%. Further increase in the percentage of steel slag and m-sand reduces the compressive strength of GFRC. Table 5: Values of Compressive Strength in MPa Mix Designation CC A0 A25 A50 A75 A100 7 days 39.2 38.5 39.7 40.3 40.9 36.1 14 days 56.1 54.7 55.4 57.8 58.5 52.3 28 days 62.4 60.2 61.4 63.5 65.1 58.2 3 © ISRASE 2015 ISRASE eXplore Digital Library Compressive Strength in MPa Second International Conference on Recent Advances in Science & Engineering-2015 70 60 50 40 7 days 30 20 14 days 10 28 days 0 CC A0 A25 A50 A75 A100 Mix Designation Figure 1: Variation of Compressive Strength with different curing periods B. Split Tensile Strength of GFRC The test results of split tensile test are as shown in Table 6. Fig 2 shows the variation of split tensile strength with various curing periods. It can be see that the split tensile strength of GFRC at 7, 14 and 28 days increases initially as the percentage of replacement of steel slag and m-sand increases and becomes maximum at a percentage around 75%. Further increase in the percentage of steel slag and m-sand reduces the split tensile strength of GFRC. Table 6: Values of Split Tensile Strength in MPa Split Tensile Strength in MPa Mix Designation CC A0 A25 A50 A75 A100 7 days 3.43 3.60 4.12 4.39 4.86 3.84 14 days 5.28 5.46 6.15 6.56 6.95 5.65 28 days 5.94 6.21 6.78 7.21 7.56 6.43 8 6 4 7 days 2 14 days 0 28 days CC A0 A25 A50 A75 A100 Mix Designation Figure 2: Variation of Split Tensile Strength with different curing periods C. Water Absorption of GFRC The test results of water absorption test are as shown in Table 7. Fig 3 shows the variation of water absorption of different mix designations. It is seen from the water absorption test, as the percentage of replacement of steel slag and m-sand increases, the water absorption ability of the specimen decreases and becomes least at a percentage around 100%. So it can be said that, the GFRC at 100 % replacement level is durable against water absorption. 4 © ISRASE 2015 ISRASE eXplore Digital Library Second International Conference on Recent Advances in Science & Engineering-2015 Table 7: Values of Water Absorption in percentage Water Absorption in % Mix Designation CC A0 A25 A50 A75 A100 28 days 1.8 1.9 1.4 1.1 1.2 0.9 2 1.5 1 0.5 0 Water Absorption Results CC A0 A25 A50 A75 A100 Mix Designation Figure 3: Water Absorption for different mix designation VI. Conclusions On the basis of experimental study in the form of strength and durability tests by using steel slag and msand as replacement of natural coarse and fine aggregate respectively, also replacement of cement with fly ash at constant 30% with glass fiber as reinforcement material for the production of GFRC, the following conclusions are drawn: 1. The compressive strength of concrete at 7, 14 and 28 days increases initially as the percentage of replacement of steel slag and m-sand increases and becomes maximum at a percentage around 75%. Further increase in the percentage of steel slag and m-sand reduces the compressive strength of concrete. 2. The split tensile strength of concrete at 7, 14 and 28 days increases initially as the percentage of replacement of steel slag and m-sand increases and becomes maximum at a percentage around 75%. Further increase in the percentage of steel slag and m-sand reduces the compressive strength of concrete. 3. The water absorption of concrete at 28 days decreases gradually as the percentage of steel slag and msand increases and becomes least at a percentage around 100%. 4. Addition of glass fibers to concrete is seen to increase the compressive and split tensile strength of concrete as replacement level is increased and becomes maximum at a percentage around 75%. 5. Optimum replacement level for steel slag and m-sand in place of natural coarse and fine aggregate respectively is found to be about 75% from the consideration of strength and durability tests of GFRC. This finding is of great importance as the natural coarse aggregate and fine aggregate is at present fast depleting and steel slag and m-sand is suitable and viable alternative for production of GFRC as replacement of natural aggregates. REFERENCES [1] [2] [3] [4] [5] [6] P. S. Kothai and R. Malathy, “Enhancement of concrete properties by steel slag as a partial replacement material for coarse aggregates,” Australian Journal of Basic and Applied Sciences, 2013, pp. 278-285. K. Chinnaraju, V. R. Ramkumar, K. Lineesh, S. Nithya and V. Sathish, “Study on concrete using steel slag as coarse aggregate replacement and ecosand as fine aggregate replacement,” International Journal of Research in Engineering & Advanced Technology, vol. 1, 2013. Nagabhushana and H. Sharada Bai, “Use of crush rock powder as replacement of fine aggregate in mortar and concrete,” International Journal of Science and Technology, vol. 4, pp. 917-922, 2011. Gobinath. R, Vijayan. V, Sivakumar. N, Prakash. P, Suganya. S, Dhinesh. A, “Strength of concrete by partially replacing the fine aggregate using m-sand,” Scholars Journal of Engineering and Technology, pp. 238-246, 2013. Er. Lakhan Nagpal, Arvind Dewagan, Er. Sandeep Dhiman and Er. Sumit Kumar, “Evaluation of strength characteristics of concrete using crushed stone dust as fine aggregate,” International Journal of Innovative Technology and Exploring Engineering, vol. 2, 2013. Shrikant Harle and Ram Meghe, “Glass fiber reinforced concrete and its properties,” International Journal of Engineering and Computer Science, vol. 2, pp. 3544-3547, 2013. 5 © ISRASE 2015 ISRASE eXplore Digital Library Second International Conference on Recent Advances in Science & Engineering-2015 [7] Mohammed Nadeem and Arun. D. Pofale, “Experimental investigation of using slag as an alternative to normal aggregates(coarse and fine) in concrete,” International Journal of Civil and Structural Engineering, vol. 3, 2012. 6 © ISRASE 2015 ISRASE eXplore Digital Library