USE OF AIR COOLED BLAST FURNACE SLAG AS A SUSTAINABLE ...ijirs.in/gallery/66. aprl ijirs d667.pdf · 1,2Assistant Professor, S.A.Engineeing College, Chennai-77, Tamilnadu, India...

USE OF AIR COOLED BLAST FURNACE SLAG AS A SUSTAINABLE MATERIAL IN CEMENT CONCRETE

S.P.Kanniyappan1, S.Saravanakumar2 1,2Assistant Professor, S.A.Engineeing College, Chennai-77, Tamilnadu, India

[email protected], [email protected]

Abstract

The present study is to investigate the properties such as physical properties, workability and strengthening properties of M25 grade concrete, in which the coarse aggregate is replaced by Air Cooled Blast Furnace Slag. This study gives the results about optimum replacement usage of Air Cooled Blast Furnace Slag (ACBFS) in the concrete to increase the strength properties. Preliminary tests were conducted to find the properties of materials used in concrete to carry out the mix design. The fresh concrete test was made to study the workability properties of partially replaced ACBFS concrete and the conventional concrete. Six mixes were prepared at different replacement levels of ACBFS (0%, 10%, 20%, 30%, 40% and 50%) with coarse aggregate and M-sand as a fine aggregate in all mixes. The compressive strength and split tensile strength of concrete was tested after 7, 14 and 28 days of curing. Results indicate that compressive and split tensile strength increases with replacement up to 30% and 40% ACBFS respectively, it is recommended that up to 30% of ACBFS can be used as coarse aggregate in concrete.

Keywords: Ordinary Portland Cement (OPC), Air-Cooled Blast Furnace Slag (ACBFS), Manufactured-Sand (M-Sand), Compressive Strength Test, Split Tensile Test.

1. INTRODUCTION

Ordinary Portland cement (OPC) is a dominant ingredient of concrete serving as bonding agent once reacted with water through the hydration process. In typical concrete mixture, OPC occupies about 15% to 20% of the total volume. That requires manufacturing of high amount of cement in order to fulfill the needs in concrete construction. To meet that high demand, more than 4 billion tons of OPC were produced every year. Of concern to the cement industry is the fact that every ton of OPC produced releases on average a similar amount of CO2 into the atmosphere. In this regard, the use of other cementitious materials (i.e. fly ash and slag cement), which are by products of other industry, have been proven to be a viable alternative. The challenges related to concrete production are not only associated with the environmental impact of cement production itself, but also with the depletion of sources of natural aggregates.

Aggregate is the main component representing the grain skeleton of the concrete mass, where all the cavities within this skeleton have to be filled with a binder paste. Similarly, aggregate constitutes approximately three quarters of the concrete volume. It is also said that, concrete comprises an essential portion of a country’s infrastructure development all over the world. Therefore, there is a considerable demand for concrete around the globe, and it is of great importance to come up with a proper replacement for its main constituent, that is natural aggregate. Concrete is made with natural sand as fine aggregate. The Shortage of good quality Natural sand (N-Sand) occurs due to depletion of natural resources and restrictions due to environmental consideration. In order to overcome these impacts an alternative has to be found in order to replace sand. The manufactured Sand (M-sand) has found to be economical alternative to the river sand. M-sand is obtained as a crushing of granite stones in required grading to be used for construction purposes as a replacement for river sand.

International Journal of Innovative Research & Studies

Volume 8, Issue IV, APRIL/2018

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1.1. Air Cooled Blast Furnace Slag (ACBFS)

Today, one of the leading ideas for natural aggregate replacement in concrete mixture is to employ steel’s co-products in concrete production, and blast furnace slag is one of them currently available; which is an industrial by-product obtained from the steel-making process. During iron production, no iron can be produced without its co-products, i.e. blast furnace slag which is a nonmetallic material. Blast furnace slag is a nonmetallic material consisting of silicates and alumino silicates of calcium and magnesium together with other compounds of sulphur, iron, manganese, and other trace elements. The final form of the blast furnace slag depends on the method of cooling. Air-cooled blast furnace slag (ACBFS) is produced through relatively slow solidification of molten blast furnace slag under atmospheric conditions, resulting in crystalline mineral formation. The physical appearance of the Air-Cooled Slag Aggregate appears suitable for use in concrete mixtures as a coarse aggregate as shown in Figure 1, because it carries good shape and a rough surface texture. ACBFS is one of the most commonly utilized reclaimed construction materials, being used as coarse aggregate in cement concrete, aggregate in hot-mix asphalt, road base material, and fill. There are economic, environmental, and social benefits derived from the effective use of ACBFS rather than disposing it as a waste.

Figure 1. Air Cooled Blast Furnace Slag (a) 10mm size, (b) 20mm size

1.2. Chemical Composition of ACBFS

The Calcinated stone have Alumina and Silica components in Iron Ore. The four major oxides present in ACBFS are CaO, SiO2, Al2O3, and MgO. These oxides are account for approximately 95% of the ACBFS composition, the remaining 5% consisting of Sulphur, Manganese, Iron, Titanium, Fluorine, Sodium, and Potassium, as given in Table 1.

Table 1. Typical Compositions of ACBFS

Composition Percentage (%)

Lime (CaO) 30-40 Silica (SiO2) 28-42 Alumina (Al2O3) 5-22 Magnesia (MgO) 5-15 Sulphur (CaS, other sulphides, sulfates) 1-2 Iron (FeO, Fe2O3) 0.3-1.7 Manganese (MnO) 0.2-1



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2. MATERIALS AND ITS PROPERTIES

2.1. General

This project aims to study the effects of application of Air Cooled Blast Furnace Slag as a sustainable material on concrete’s strength properties.

2.2. Materials Used

Ordinary Portland Cement Coarse Aggregate Fine Aggregate Water Air cooled blast furnace slag.

2.3. Cement

In this study, Ordinary Portland Cement (OPC) of grade 53 as shown in Figure 2 from a single lot of Penna Cement as per specification given in IS:12269 -1987 was used for the investigation. It was fresh and free from any lumps. Cement was carefully stored to prevent deterioration in its properties due to contact with the moisture, its physical properties are shown in Table 2.

Figure 2. Ordinary Portland Cement

Table 2. Physical Properties of Cement

S.No. Property Values Obtained 1 Specific Gravity 3.15 2 Standard Consistency Test 28% 3 Initial Setting Time 40 minutes 4 Final Setting Time 9 hours

2.4. Coarse Aggregate

The aggregates which are retained on the IS sieve of particle size 4.75 mm are termed as Coarse aggregate. The coarse aggregate used in this investigation is confirming to IS: 383-1987. The aggregates shown in Figure 3, were washed to remove dirt, dust and then dried to surface dry condition. The aggregates were grey in color, angular in shape. The physical properties of the aggregate is determined as per IS specification. Table 3 shows the physical properties of coarse aggregate.



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Figure 3. Coarse Aggregate

Table 3. Physical Properties of Coarse Aggregate

S.No. Property Value Obtained 1 Specific Gravity 2.7 2 Water Absorption 0.9 3 Particle Shape and Texture Angular and Rough 4 Aggregate Crushing Value 16.2 5 Aggregate Impact Value 18.3

2.5. Fine Aggregate

The M-sand which was locally available and passing through 4.75 mm IS sieve as shown in Figure 4 is used. It was coarse sand, brown in color. Fine aggregates confirming to grading zone II as per IS- 383-1987 were used. Specific gravity of fine aggregates was experimentally determined as 2.64. The sieve analysis and the physical properties of fine aggregate are shown in Table 4 & 5 respectively.

Figure 4. Fine Aggregate (M-Sand)

Table 4. Sieve Analysis of Fine Aggregate

S.No. Sieve Size

Weight Retained (gm)

% Weight Retained

Cumulative % Retained

% Passed

1 10 mm 0 0 0 100 2 4.75 mm 0 0 0 100 3 2.36 mm 42 4.2 4.2 95.8 4 1.18 mm 186 18.6 22.8 77.2 5 600 micron 316 31.6 54.4 45.5 6 300 micron 354 35.4 89.8 10.2 7 150 micron 102 10.2 100 100

Therefore, Fineness modulus of aggregate = (cumulative % retained) / 100 = 2.70



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Table 5. Physical Properties of Fine Aggregate

S.No. Property Value Obtained 1 Specific Gravity 2.64 2 Fineness Modulus 2.70 3 Zone II 4 Surface Texture Smooth

2.6. Water

This is the least expensive but most important ingredient of concrete. The quantity and quality of water required to be looked in to very carefully. It should be free from organic matter and the pH value should be between 6 to 7.The physical a property of water is shown in Table 6.

Table 6. Physical Properties of Water

S.No. Property Value Obtained 1 pH 7 2 Taste Agreeable 3 Appearance Clear

2.7. Air Cooled Blast Furnace Slag

Air cooled blast furnace slag as shown in Figure 5 is collected from Suryadev Alloys and Power Private Limited, Gummidipoondi. Then, it is crushed into required sizes and their physical properties have been studied. Table 7 shows the physical properties of ACBFS.

Figure 5. Air Cooled Blast Furnace Slag

Table 7. Physical Properties of ACBFS

S.No. Property Value Obtained 1 Specific Gravity 2.4 2 Water Absorption 4 3 Particle Shape and Texture Angular and Roughly Cubical 4 Aggregate Crushing Value 27.3 5 Aggregate Impact Value 28.5



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3. MIX PROPORTION

The Mix Design for M25 Grade Concrete as per the Guidelines from IS 10262:2009 is given by the mix ratios,

Cement = 447 Kg Water = 197 liters Fine aggregate = 768 Kg Coarse aggregate = 1018 Kg W/C = 0.44

Mix Proportion 1: 1.7: 2.2

4. TEST RESULTS AND DISCUSSIONS

4.1. General

To study and compare the behavior of concrete using ACBFS as the replacement of coarse aggregate, various experimental investigations as mentioned above were carried out on concrete samples for their strength and workability properties. To compare the test results, control concrete and ACBFS replaced concrete were tested for all its replacements.

The concrete samples were casted as shown in Figure 6, with mix proportion of M25 grade concrete. The tests were carried out after 28 days of water curing. Summary of the test result were discussed and recorded in tables. The percentage variation in properties of concrete using ACBFS as partial replacement of coarse aggregate, with respect to that of normal concrete is also tabulated for comparative study.

Figure 6. Casting & Curing of Test Specimens

4.2. Tests Results on Fresh Concrete (Workability Test)

The Slump Cone test as shown in Figure 7 is carried out to determine the workability characteristics of fresh concrete. The variation in workability characteristics of fresh concrete for 0%, 10%, 20%, 30%, 40% and 50% ACBFS replacement were determined and the test results are formulated in the Table 8.



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Figure 7. Slump cone test

Table 8. Slump Cone Test Result

4.3. Test Results on Hardened Concrete

4.3.1. Compressive Strength Test

This test is considered as one of the most important properties of concrete and it is often used as an index of the overall quality of concrete. For this, the cubes were tested as shown in Figure 8 for its compressive strength at the age of 7th, 14th & 28th day.

Figure 8. Compression Strength Testing

Table 9. 7th Day Testing (M 25)

S.No. Percentage of ACBFS

Slump Value (mm)

Type of Slump

1 0 100 True Slump 2 10 100 True Slump 3 20 105 True Slump 4 30 110 True Slump 5 40 110 True Slump 6 50 105 True Slump

S.No. % of ACBFS

W/C Ratio

CUBE

Weight (Kg)

Load (KN) Compressive Strength (N/mm2)

1 0 % 0.44 8.041 438 19.46 2 10 % 0.44 7.939 456 20.26 3 20 % 0.44 7.978 468 20.80 4 30 % 0.44 7.836 489 21.73 5 40 % 0.44 7.805 494 21.06 6 50 % 0.44 7.789 443 19.68



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Figure 9. 7th Day Compression Test Result The 7th day test results as shown in Table 9 & Figure 9 indicates that the compressive strength

increases by 4.1%, 6.8%, 11.6%, 8.2%,1.1% for the replacement of 10%, 20%, 30%, 40% and 50% ACBFS respectively. The increase in compressive strength slightly reduces above 30% replacement.


S.No. % of ACBFS

W/C Ratio

CUBE Weight

(Kg) Load (KN)

Compressive Strength (N/mm2)

1 0 % 0.44 8.113 569 25.28 2 10 % 0.44 8.141 628 27.91 3 20 % 0.44 8.079 647 28.75 4 30 % 0.44 8.012 693 30.80 5 40 % 0.44 7.792 671 29.82 6 50 % 0.44 8.039 635 28.82

Figure 10. 14th Day Compression Test Result

The 14th day test results as shown in Table 10 & Figure 10 indicates that the compressive strength increases by 10.4%, 13.7%, 21.8%, 17.9%, 14% for the replacement of 10%, 20%, 30%, 40% and 50% ACBFS respectively. The increase in compressive strength slightly reduces above 30% replacement.



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Figure 11. 28th Day Compression Test Result

The 28th day test results as shown in Table 11 & Figure 11 indicates that the compressive strength increases by 8.5%, 13.5%, 19.4%, 16.6%, 10.3% for the replacement of 10%, 20%, 30%, 40% and 50% ACBFS respectively. The increase in compressive strength slightly reduces above 30% replacement. 4.3.2. Split Tensile Test

The tensile strength of concrete is one of the basic and important properties. Split tensile strength test on concrete cylinder is a method to determine the tensile strength of concrete. Split tensile strength of concrete is found by testing concrete cylinder of size 100 mm x 200 mm. The specimens were tested for its strength as shown in Figure 12 as per IS: 516-1959 using a calibrated compression testing machine of 2000 KN capacity. The cylindrical specimens were tested for its split tensile strength at the age of 7, 14 & 28th day.

S.No. % of ACBFS

W/C Ratio

CUBE Weight

(Kg) Load (KN)

Compressive Strength (N/mm2)

1 0 % 0.44 8.248 672 29.86 2 10 % 0.44 8.216 729 32.40 3 20 % 0.44 8.172 763 33.91 4 30 % 0.44 8.146 802 35.64 5 40 % 0.44 8.159 784 34.84 6 50 % 0.44 8.112 741 32.93



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Figure 12. Split Tensile Strength Testing


S.No. % of ACBFS

W/C Ratio

CYLINDER Weight

(Kg) Load (KN)

Split Tensile (N/mm2)

1 0 % 0.44 3.276 72 2.29 2 10 % 0.44 3.243 79 2.51 3 20 % 0.44 3.231 83 2.64 4 30 % 0.44 3.218 92 2.92 5 40 % 0.44 3.176 95 3.11 6 50 % 0.44 3.145 86 2.73

Figure 13. 7th Day Split Tensile Strength Test Result

The 7th day test results as shown in Table 12 & Figure 13 indicates that the split tensile strength increases by 9.6%, 15.3%, 27.5%, 35.8%, 19.2% for the replacement of 10%, 20%, 30%, 40% and 50% ACBFS respectively. The increase in split tensile strength slightly reduces above 40% replacement.



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S.No. % of ACBFS

W/C Ratio

CYLINDER Weight

(Kg) Load (KN)


1 0 % 0.44 3.291 97 3.08 2 10 % 0.44 3.253 113 3.59 3 20 % 0.44 3.277 126 4.01 4 30 % 0.44 3.236 138 4.39 5 40 % 0.44 3.189 142 4.52 6 50 % 0.44 3.143 117 3.72




S.No. % of ACBFS

W/C Ratio

CYLINDER Weight

(Kg) Load (KN)


1 0 % 0.44 3.316 122 3.88 2 10 % 0.44 3.329 129 4.10 3 20 % 0.44 3.261 143 4.55 4 30 % 0.44 3.258 152 4.83 5 40 % 0.44 3.242 157 4.99 6 50 % 0.44 3.171 135 4.29



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5. SUMMARY AND CONCLUSION

5.1. Summary

The main aim of this project was to study the behavior of concrete and changes in the properties of concrete with replacing the use of natural coarse aggregates by air cooled blast furnace slag. The demand for aggregates is increasing rapidly and so as the demand of concrete. Thus, it is becoming more important to find suitable alternatives for aggregates in the future. Air cooled blast furnace slag is a byproduct and using it as aggregates in concrete will might prove an economical and environmentally friendly solution.

A thorough literature review was conducted to study and investigate the properties of air cooled blast furnace slag aggregates. The results showed that it has properties similar to natural aggregates and it would not cause any harm if incorporated into concrete. In this project the mix design was prepared for M25 grade concrete based on IS specifications and is verified by casting and testing the specimens. A comparison study of concrete with various percentages (0%, 10%, 20%, 30%, 40%, and 50%) of air cooled blast furnace slag aggregates as coarse aggregate and using the M-sand as the fine aggregate was made. The results are found confirming to the standards and in future researches incorporating of ACBFS in the concrete was to be made.

5.2. Conclusion

The workability and strength properties of concrete mixes have been studied at the replacing of 0%, 10%, 20%, 30%, 40% and 50% ACBFS in coarse aggregate. On this study, the following conclusions are drawn.

The Slump value is more when coarse aggregate is replaced with 30% and 40% by ACBFS. So we can conclude that for 30% and 40%, workability would be more compared to remaining mixes.

The Compressive strength is maximum of 35.64 MPa with the replacement of 30% ACBFS at the age of 28 days.

The Split tensile strength is maximum of 4.99 MPa with the replacement of 40% ACBFS at the age of 28 days.



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Thus, from the above results it can be concluded that the replacement of ACBFS up to 30% in concrete is found to be good and economic.

References Journal Articles

[1] Ali Fallah Pour, Togay Ozbakkaloglu, Lei Gu (2016), ‘Normal and High-Strength Concretes incorporating Air-Cooled Blast Furnace Slag Coarse aggregates’, Construction and Building Materials, pp.138-146, March 2016.

[2] Bhaveshkumar M. Kataria, Sandip U. Shah (2015), ‘A Behavioral Study of Cement Concrete with Manufactured Sand’, International Journal of Science Technology & Engineering [IJSTE], volume 2, Issue 01, July 2015.

[3] E.V.Chandra Sekhar, K.Spandana, K.Raja Sekhar (2016), ‘Strength Properties of Replacement of Air Cooled Blast Furnace Slag in Fine Aggregate’, International Journal of Core Engineering & Management [IJCEM], Volume 3, Issue 6, September 2016.

[4] Hong-Gi Kim, Jae-Suk Ryou (2017), ‘Influence of Air-Cooled Blast Furnace Slag Aggregate on Sulfate Attack Resistance’, Journal of Ceramic Processing Research [JCPR], Volume 18, pp. 27-35, April 2017.

[5] Irfanullah Irfan, Hiroyuki Tobo, Yasutaka Ta (2017), ‘Study on the Utilization of Innovative Air-Cooled Slag Aggregates in Precast Concrete’, International Journal of Structural and Civil Engineering Research [IJSCER], Volume 6, November 2017.

[6] Dr. Jaspal Singh, Dr. Gurpreet Singh Dhanoa, Rajindervir Singh Sandhu (2015), ‘Use of Air Cooled Blast Furnace Slag (ACBFS) as Coarse Aggregates‐ A Case Study’, International Journal of Innovations in Engineering Research and Technology [IJIERT], Volume 2, Issue 4, April 2015.

[7] Dr. B. Krishna Rao, Dr.M.Swaroopa Rani (2015), ‘Replacement Of Natural Coarse Aggregate With Air Cooled Blast Furnace Slag An Industrial By Product’, International Journal of Engineering Research and Applications [IJERA], Volume 5, Issue 7, pp.36-40, July 2015.

[8] P. Magudeaswaran, Dr. P. Eswaramoorthi (2016), ‘High Performance Concrete using M Sand’, Asian Journal of Research in Social Sciences and Humanities [AJRSSH], Volume 6, Issue 6, pp. 372-386, June 2016.

[9] K.U.Manikandhan, N.Sathya Kumar, R.Sakthivel (2015), ‘Effect of Replacement of River Sand by M-sand in High Strength Concrete’, International Journal of Modern Trends in Engineering and Research [IJMTER],Volume 02, Issue 02, February 2015.

[10] R. Manogna, T.N. Guruprasad (2017), ‘Experimental Study on the Properties of PFRC using M-Sand’, International Research Journal of Engineering and Technology [IRJET], Volume 04, Issue 06, June 2017.

[11] S. Naveen Kumar, M. Y. A. Harika, Mohammed Ismail (2017), ‘Experimental Investigation on Self Compacting Concrete by Partial Replacement of Coarse Aggregate with Air Cooled Blast Furnace Slag’, International Journal for Scientific Research & Development[IJSRD], Volume 5, Issue 06, 2017.

[12] Dr. T. B. Pradeep Kumar, Prem Ranjan Kumar (2015), ‘Use of Blast Furnace Slag as an Alternative of Natural Sand in Mortar and Concrete’, International Journal of Innovative Research in Science, Engineering and Technology [IJIRSET], Volume 4, Issue 2, February 2015.

[13] K.Praveen Kumar, Radhakrishna (2016), ‘Characteristics of SCC with Fly Ash and Manufactured Sand’, Materials Science and Engineering, June 2016.

[14] Rajindervir Singh Sandhu, Jaspal Singh, Gurpreet Singh Dhanoa (2015), ‘Effect of Air Cooled Blast Furnace Slag and Polypropylene Fibre on Mechanical Properties of Concrete’, International Journal of Civil, Structural, Environmental and Infrastructure Engineering Research and Development [IJCSEIERD], Volume 5, Issue 3, June 2015.

[15] P. T. Ravichandran, C. Sudha, K. Divya Krishnan , P. R. Kannan Rajkumar and A. Anand (2016), ’Study on Mechanical Properties of High Performance Concrete using M-Sand’, Indian Journal of Science and Technology [IJST], Volume 9, February 2016.

[16] Shervin Jahangirnejad, Thomas Van Dam, Dennis Morian (2013), ‘Use of Blast Furnace Slag as a Sustainable Material in Concrete Pavements’, Transportation Research Board [TRB], July 2013.



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[17] Shivang. D. Jayswal, A. G. Hansora, A. A. Pandya (2014), ‘Effect of Replacement of Natural Sand by M-Sand as Fine Aggregate in Concrete’, International Journal for Scientific Research & Development [IJSRD], Volume 2, Issue 10, March 2014.

[18] C. Sudha, P. T. Ravichandran, K. Divya Krishnan, P. R. Kannan Rajkumar (2016), ‘Strength Characteristics of High Strength Concrete using M-sand’, Indian Journal of Science and Technology[IJST],volume 9, November 2016.

[19] A.S. Wayal, Nimitha Vijayaraghavan (2013), ‘Effects of Manufactured Sand on Compressive Strength and Workability of Concrete’, International Journal of Structural and Civil Engineering Research [IJSCER], Volume 2, November 2013.

[20] M.Yajurved Reddy , D.V. Swetha, S. K. Dhani (2015), ‘Study on Properties of Concrete with Manufactured Sand as Replacement to Natural Sand’, International Journal of Civil Engineering and Technology [IJCIET], Volume 6, Issue 8, pp. 29-42, August 2015.

Text Books

[1] M.S.Shetty, Concrete Technology Theory and Practice, S.Chand & Company Ltd., Ram Nagar, New Delhi-110 055.

[2] M.L.Gambhir, Concrete Technology Theory and Practice, Tata McGraw-Hill publishing company Ltd., New Delhi-110 020.

[3] S.S.Bhavikatti, Concrete Technology, I.K. International Publishing House Pvt. Ltd., New Delhi-110 002.

Code Books

[1] IS: 10262-1982 (Reaffirmed 2004): Recommended guidelines for concrete mix design, Bureau of Indian Standard, New Delhi-2004.

[2] IS: 383-1970 (Reaffirmed 1997): Specification for Coarse and Fine Aggregates from Natural Sources for Concrete, Bureau of Indian Standard, New Delhi-1997.

[3] IS: 516-1959 (Reaffirmed 2004): Methods of tests for strength of concrete, Bureau of Indian Standard, New Delhi 2004.



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USE OF AIR COOLED BLAST FURNACE SLAG AS A SUSTAINABLE ...ijirs.in/gallery/66. aprl ijirs d667.pdf · 1,2Assistant Professor, S.A.Engineeing College, Chennai-77, Tamilnadu, India...

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