Mechanical Characteristics of Eco-friendly Concrete Using GGBS and Manufactured Sand

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International Journal of Excellence Innovation and Development ||Volume 2, Issue 1, Jan. 2019||Page No. 025-028||

Mechanical Characteristics of Eco-friendly Concrete Using GGBS and Manufactured Sand P. Karthigai Balan Assistant professor, Department of Civil Engineering, Saranathan College of Engineering, Tiruchirappalli, Tamilnadu, India

Abstract––This paper describes the properties of concrete with partially replacing the M-Sand for fine aggregate and GGBS for Cement. M25 grade of concrete was used for this project. M sand was partially replaced about 0%, 25%, 30%, 35%, 40% and 50%% in the weight of fine aggregate. GGBS was partially replaced constantly about 10% in the weight of cement. The compressive strength and flexural strength of the concretes were tested and compared with the strength of the conventional concrete at the curing ages of 7, 14 and 28 days of curing. Test results show that the maximum strength was attained at 40% replacement of M sand. So the optimum replacement of M sand is 40% in the weight of fine aggregate. Further increase in the percentage of M sand reduces the strength of concrete than the conventional concrete. Keywords––Eco-friendly concrete, GGBS, M-sand, Strength

INTRODUCTION Concrete is prepared by mixing various constituents like cement, aggregate, water, etc. Which are economically available. Concrete is a composite material composed of granular like coarse aggregate embossed in a matrix and bound together with cement or binder which fills the space between the particles and glues them together. Almost three quarters of the concrete is composed of concrete. To meet the global demand of concrete in future, it is becoming a more challenging task to find suitable alternate to natural aggregate for preparing concrete. Therefore in India the use of alternate sources for natural aggregate is becoming increasingly important. GGBS is a co product of iron making industry. The use of blast furnace slag aggregate in concrete by replacing natural aggregate is most promising concept because its impact strength is more than the natural aggregate. Steel slag aggregate are already being used as aggregate in asphalt paving road mixes due to their mechanical strength. The cheapest and easiest alternate to natural sand is manufactured sand by crushing rocks or stones in desire sizes and trade by suitable methods. Sand produced by such means is known as manufactured/crusher/artificial sand.

LITERATURE REVIEW Nimitha Vijayaragavan and A S Wayal The cheapest and easiest alternative to natural sand is manufactured sand produced by such a means is known as manufactured crusher or artificial sand. The paper presents the result of experimental investigation of www.ijeid.com

partial and full replacement natural sand by manufactured sand. The main aim of the paper is to compare the compressive strength and workability of concrete with manufactured sand and natural sand in various proportions. M. Adams Joe, A. Maria Rajesh, P. Brightson, M. Premanand The natural river sand was the cheapest resource of sand. Compared to the river sand M-sand have a better quality with more bonding strength. From the experiments results it is concluded that the M-sand can be used as a replacement for fine aggregate. It is found that 50% replacement of fine aggregate by M-sand give maximum result in strength and durability aspects than the conventional concrete. K.G. Hiraskar and Chetan Patil Blast furnace slag is a by product and using it as aggregate in concrete will might prove an economical and eco friendly solution in local region. The demand for aggregate is increasing rapidly and so as the demand of concrete. The results shows that it has properties similar to natural aggregates and it would not cause any harm if incorporated into concrete. There is no negative effects.

EXPERIMENTAL INVESTIGATION Cement Cement is the most important constituent of concrete, it forms the binding, medium for the discrete ingredients made out of naturally occurring raw materials and sometimes blended or inter ground with industrial wastes. Cement comes in various type and chemical compaction. For our project we have used OPC 53 grade.

Sl. No 1 2 3 4

Table 1: Physical properties of cement Property Values Standard Obtained Value Initial setting time (min) 48 >30 Final setting time(min) 240 <600 Fineness 3.5 <10 Specific gravity 3.07 -

Fine aggregate Locally available river sand having bulk density of 1.71 kg/m3. Specific gravity of 2.65 and fineness of 5.24.

MANUFACTURED SAND M-sand used as partial &full replacement for river sand having bulk density of 1.75 kg/m3. Specific gravity of 2.73 and fineness of 5.24.

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Mechanical characteristics of eco-friendly concrete using GGBS and manufactured sand Table 2: Comparison between river sand and M-sand. Sl. Property River Sand Manufactured No Sand 1 Particle passing Less than Less than 15 75 microns 3% 2 Specific gravity 2.3 - 2.7 2.5 - 2.9 3 Water Absorption 1.5 - 3 % 2 - 4% 4 Surface moisture Up to 7% Up to 10 % 5 Soundness value Less Relatively sound(>5) sound(<5) Table 3: Sieve analysis comparison between natural and river sand. IS Sieve River Sand (%) M-Sand (%) 4.75 mm 99.25 99.75 2.36 mm 93.50 78.25 1.18 mm 48.00 52.00 600 Microns 21.00 38.00 300 Microns 04.00 21.00 150 micron 0.05 05.00 Coarse aggregate Natural coarse aggregate Crushed natural aggregates with maximum grain size of 20 mm with standard abrasion value and impact and crushing strength value. Table 4: Mechanical properties of Natural Coarse aggregate. Sl. No Property Obtained Value 1 Type Crushed 2 Maximum size 20mm 3 Specific gravity 2.50 4 Total water absorption 0.5% 5 Moisture content 0.7% 6 Fineness modulus 7.6 7 Impact value 18.40% GGBS aggregate Generally steel possess high tensile strength and impact strength and stee slag is used as an aggregate as an aggregate to improve the flexural and tensile strength of concrete and steel slag will also be an economical replacement compared with conventional aggregate. Ground Granulated Blast Furnace Slag is an industrial by product obtained from the extraction of ‘iron’ from ores which is a complex process requiring a number of other materials which are added as flux or catalysts. After making steel these ingredients forming a matrix are to be periodically cleaned up. Removed in bulk, it is known as steel-slag. This steel slag consists of silicates and oxides. Therefore here, GGBS is used as an aggregate to produce concrete of good tensile strength and flexural strength. Table 5: Chemical Compositions of GGBS aggregate. Chemical constituent Portland cement GGBS CaO 65% 40% SiO2 20% 35% Al2O3 5% 10% MgO 2% 8% www.ijeid.com

S. No 1 2 3 4

Balan PK

Table 6: Properties of steel slag. Property Values obtained Type Uncrushed Density 3.6kg/m³ Water absorption 2.5% Impact value 28%

Water Mixing water quality is required in accordance with the quality standards of drinking water, the use for PH> 4 clean water.

WORKABILITY TESTS Slump Cone Test Slump cone test is one of the most commonly used method of measuring consistency of concrete. Consistency of concrete can be measure with the workability of concrete by determining the slump value. The test is conducted as per the standard procedure for different samples and the slump value for all those samples were found out. The slump value of concrete is 58mm at the W/c ratio of 0.5 Compaction Factor Test Compaction factor value of concrete is very much useful to determine the workability of concrete. This process done with compaction factor testing apparatus. The test was conducted as per procedure and the different weight of cylinder is noted when partially compacted and fully compacted conditions. And the compaction factor value of concrete is 93% at the W/c ratio of 0.5. Vee Bee Consistometer Test To determine the workability of fresh concrete by using a Vee – Bee consistometer as per IS: 1199 – 1959. The apparatus used is Vee- Bee consistometer. This results the workability of concrete at different W/c ratio. And the allowable vee-bee value is noted and used for different uses. When applying w/c ratio of 0.5, the concrete become stiff and the Vee- Bee result is 8 seconds. The workability of the given concrete concluded that the concrete is suitable for medium workability.

MIX PROPORTION OF CONCRETE We are used M25 type of concrete for testing of concrete. And the calculated mix proportion value of the M25 concrete is given below, Table 7: Mix proportion for m25 concrete. Water Cement Fine Coarse (Litres/m³) (Kg/m3) Aggregate Aggregate (Kg/m3) (Kg/m3) 199 398 652 1109 0.50 1 1.64 2.80

TESTING OF HARDENED CONCRETE Compressive strength test An important property of hardened concrete is the compressive strength it is determined by a compression test on specially produced specimens. The main factor influencing compressive strength are the type of cement, the W/C ratio and the degree of hydration which is affected mainly by the curing time and method.

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International Journal of Excellence Innovation and Development ||Volume 2, Issue 1, Jan. 2019||Page No. 025-028|| The compressive strength of the concrete is tested at the curing intervals of 7 days, 14 days and finally 28 days. Table 8: Observations and Results in Compressive strength test. Grade Percentage of Compressive strength Replacement (N/mm²) 7 days 14 days 28 days M25 M-sand GGBS 0 10 16.33 22.76 24.6 25 10 16.50 22.14 20.0 30 10 16.43 22.44 24.9 35 10 16.67 22.55 23.2 40 10 18.42 23.65 25.8 45 10 15.23 21.45 24.0 50 10 14.0 20.10 23.1

Table 9: Observations and results in flexural strength test. Grade Percentage of Flexural strength Replacement (N/mm²) 7 days 14 days 28 days M25 M-sand GGBS 0 10 2.87 3.38 4.20 25 10 2.62 3.21 4.10 30 10 2.68 3.27 4.0 35 10 2.71 3.33 4.30 40 10 2.59 3.22 4.60 45 10 2.41 3.10 4.23 50 10 2.39 3.0 4.34

Flexural Strength Test 5

Conventional

4.5

Compressive Strength Test 35

25%MS 10% GGBS 30%MS 10%GGBS 35%MS 10%GGBS 40%MS 10%GGBS 45%MS 10%GGBS 50%MS 10%GGBS2

4 3.5

Convention

3

30

2.5

25

25%MS 10%GGBS 30%MS 10%GGBS

1.5

20

15

35%MS 10%GGBS

0.5

10

40%MS 10%GGBS

5

45%MS 10%GGBS

0

50%MS 10%GGBS 7 days

14 days 28 days

Result 75% replacement of natural river sand by M-Sand and 20 % replacement of natural aggregate by GGBS aggregate results in increasing the compressive strength of the concrete. Flexural strength test Flexural strength of concrete is the ability of a concrete to resist failure in bending.. Flexural strength is an significant characteristic of concrete as concrete in structures are mostly subjected to bending. Flexural strength is performed by casting prism. The specimens are well cured with water as short period of drying can produce a sharp drop in flexural strength. It is therefore the specimens are well cured and the test results were calculated for 7 days, 14 days and 28 days respectively. The flexural strength of concrete prism specimen is to be expressed as the modulus of rupture fb and was investigated by measuring the load and it was calculated by using the equation. www.ijeid.com

2

1

0 7 days

14 days

28 days

CONCLUSION Experimental study on replacement of natural river sand by M-sand and natural coarse aggregate by GGBS aggregate shows the successful results of a. Natural sand replaced by M-sand at the ratios of 25%, 50%, 75% and 100% b. Natural Coarse aggregate replaced by GGBS aggregate at the ratios of 0%, 10%, 20%, and 30%. c. 75% replacement of fine aggregate by M-sand and 20% replacement of coarse aggregate by GGBS aggregate gives optimum strength. d. The result proves that the M-sand is a perfect alternate to river sand at the ratio of 75% e. GGBS aggregate proved the strength development in Eco-Friendly concrete at the ratio of 20%. f. The positive result comes by the irregular shape, size of both M-sand and GGBS aggregate, which provides better bonding between the particles in concrete. g. The successful result shows the positive in replacement of Manufactured sand at the ratio of 75% and GGBS as 20%.

REFERENCE [1]

Studies on strength behaviour of high volumes of slag concrete. By T. Vijayagowri and P. Srinivasan Rao.

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Mechanical characteristics of eco-friendly concrete using GGBS and manufactured sand [2]

Determination of mechanical strength for high grade concrete by partial Replacement of M sand by Abhishekkullkarni, Kalayani Bhutada on issue May 05 2014.

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[3]

Balan PK

Effects of M sand on compressive Strength and Workability of concrete. By A.S Wayal Nimitha Vijayaragavan on issue 2013.

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