GGBS PPT

EFFECTS OF GGBS ON GEOTECHNICAL PROPERTIES OF

BLACK COTTON SOIL

Under the guidance ofShri. B.M. Gudadappanavar

Assistant Professor DEPARTMENT OF CIVIL ENGINEERING

PRESENTED BY:ABHIJEET KUMAR SINGH 2SD11CV001AQUIB NASIR RAZI 2SD11CV009DIBYAJYOTI SARMA 2SD11CV020KAMLESH KUMAR 2SD11CV031

8th Semester B.E., Civil Academic Year: 2014-2015

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CONTENTS

1. INTRODUCTION2. LITERATURE REVIEW3. OBJECTIVE OF THE STUDY4. WHAT IS GGBS ?5. METHODOLOGY6. CONCLUSION

REFERENCES

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Innovative methods of soil stabilization are in great demand all over the world.

Black cotton soil which is occupying nearly 23% of the area in India is a problematic soil, available up to a depth of 3.7 meters on an average. The black cotton soil has various problems like less stability, less shear strength and large expansion & shrinkage in volume with changing seasons.

These demerits obstruct construction like big infrastructure, road pavements, etc. on this soil.

Ground Granulated blast furnace slag(GGBS) have puzzolanic properties and are being used in the construction industry along with cement or lime as activators.

Very few researchers have done some work in the stabilization of black cotton soils using GGBS.

INTRODUCTION

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LITERATURE REVIEWVarious researchers evaluated the potential of GGBS to stabilize soil. Gyanen Takhelmayum, Savitha, Krishna Gudi (March 2013) carried out a series

of test on black cotton soil with various proportions of GGBS . They concluded that addition of GGBS to black cotton soil in various percentages affects the compaction characteristic which is primarily due to alteration of gradation of soil mixtures. The increase of the maximum dry unit weight with the increase of the percentage of GGBS is mainly due to the higher specific gravity of the fine GGBS compared with expansive soil and the immediate formation of cemented products by hydration which increases the density of soil.

Laxmikant Yadu and Dr. R.K. Tripathi(2013) studied the effects of GGBS in the engineering behavior of soft soil. The study and experimental results indicated that the use of GGBS had significantly improved the physical and strength properties of the soil and reduced swelling behavior of the soil.

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LITERATURE REVIEWo K V Manjunath ,Himanshu Shekhar ,Manish Kumar ,Prem Kumar and

Rakesh Kumar (2012) studied and carried out test to stabilize black cotton soil using GGBS and concluded that the use of GGBS had enhanced the engineering properties of the black cotton soil and had increased the stability of the soil and Unconfined Compressive Strength had increased after the percentage addition of GGBS to the soil. Which came out to be an economical solution and partial replacement of ordinary Portland cement.

OBJECTIVE OF THE STUDY

To study the effects of Ground Granulated Blast Furnace

Slag(GGBS) on the Engineering performance of black cotton

soil and to check if it can be used as a soil stabilizer.

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WHAT IS GGBS ? Ground granulated blast furnace slag (GGBS) is a by-product

from the blast-furnaces used to make iron. These operate at a temperature of about 1,500 degrees centigrade and are fed with a carefully controlled mixture of iron-ore, coke and limestone.

The iron ore is reduced to iron and the remaining materials form a slag that floats on top of the iron. This slag is periodically tapped off as a

molten liquid and if it is to be used for the manufacture of GGBS it has to be rapidly quenched in large volumes of water.

7GGBS

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o The quenching, optimizes the cementitious properties and produces granules similar to a coarse sand. This ‘granulated’ slag is then dried and ground to a fine powder.

BENEFITS OF USING GGBSThe major benefits of using GGBS are: better workability, making placing and compaction easier lower early-age temperature rise, reducing the risk of thermal

cracking in large pours high resistance to chloride ingress, reducing the risk of reinforcement

corrosion

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METHODOLOGYIn this study, we have studied the variation in properties of black cotton soil on addition of varying percentages of GGBS and the following tests were carried out:-

Test on Atterberg’s Limits Grain Size Distribution Free Swell Index Maximum Dry Density Unconfined Compressive Strength California Bearing Ratio

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MATERIALS USED

Black cotton soil : The soil used for this study were collected from Y.S. Colony, Dharwad , Karnataka at a depth of 0.5 m.

GGBS : It was procured from PWD Dharwad and they had brought it from Jindal Vijayanagar Steel Ltd in Toranagallu, Bellary, Karnataka

PROPERTIES OF BLACK COTTON SOIL

SOIL CHARACTERISTICS DESCRIPTIONMaximum dry density 1.396 g/cc

Optimum moisture content 16%Specific gravity 2.63

UCS 220 kPaCBR (SOAKED) 2.36 %

Free swelling index 60%Liquid limit 68%Plastic limit 25%

Plasticity index 43%

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BC SOIL + FINE GGBS

LIQUID LIMIT(WL)

PLASTIC LIMIT(WP)

PLASTICITY INDEX (IP)

100% + 0% 68% 25% 43%90% + 10% 75% 42.85% 32.15%80% + 20% 61% 42.85% 18.15%70% + 30% 49% 42.85% 6.15%

ATTERBERG’S LIMITS (IS:2720(PART 5)-1985)

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NOTE: As per MORTH specifications the plasticity index of soils to be used for embankments, subgrades, earthen shoulders and miscellaneous backfills should be less than 25.

PLASTICITY INDEX OF GGBS MIXES

0

5

10

15

20

25

30

35

40

45

50

0 10 20 30

PLAS

TICI

TY IN

DEX

(%)

GGBS(%)14

GRAIN SIZE DISTRIBUTION (IS: 2720 (PART 4)-1985)

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SL.NO IS SIEVEPARTICLE

SIZE D(mm)WEIGHT

RETAINED(g)

PERCENT RETAINED

CUMMULATIVE %RETAINED

CUMMULATIVE % FINER

1 100mm 100 0 0 0 100

2 63mm 63 0 0 0 100

3 20mm 20 0 0 0 100

4 10mm 10 0 0 0 100

5 4.75mm 4.75 6 0.6 0.6 99.46 2mm 2 18 1.8 2.4 97.67 1mm 1 12 1.2 3.6 96.48 600micron 0.6 0 0 3.6 96.49 425micron 0.425 11 1.1 4.7 95.310 300micron 0.3 8 0.8 5.5 94.511 212micron 0.212 7 0.7 6.2 93.812 150micron 0.15 9 0.9 7.1 92.913 75micron 0.075 14 1.4 8.5 91.514 PAN <0.075 915 91.5 100

GRAIN SIZE DISTRIBUTION GRAPH

160.01 0.1 1 10 10086

88

90

92

94

96

98

100

102

PARTICLE SIZE IN MM

PER

CEN

TAG

E FI

NER

(N

)

GRAIN SIZE ANALYSIS

% OF GRAVEL 0.6

% OF SAND PARTICLES 7.9

% OF SILT and CLAY 91.5

SOIL CLASSIFICATION

INDIAN STANDARD SOIL CLASSIFICATION CH

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NOTE: As per MORTH specifications any soil that classifies as OL, OH , or Pt are considered as unsuitable for the construction of embankments.

FREE SWELLING INDEX (IS: 2720(PART 40)- 1977)

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BC SOIL + GGBS

FREE SWELLING INDEX(%)

100% + 0%

60

90% + 10%

40

80% + 20%

20

70% + 30%

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MAX DRY DENSITY OF BC SOIL ON ADDITION OF FINE GGBS(IS: 2720(PART 8)- 1983)

1.2

1.3

1.4

1.5

1.6

1.7

1.8

10 12 14 16 18 20

MAX

DRY

DEN

SITY

(g/c

c)

OPTIMUM MOISTURE CONTENT (%)

BC SOIL10% GGBS20% GGBS30% GGBS

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BC SOIL + FINE GGBS

O.M.C(%) ρ (g/cc)100% + 0% 16 1.396 (13.63

KN/m3)90% + 10% 15 1.43 (14.03 KN/m3)80% + 20% 14 1.46 (14.32 KN/m3)70% + 30% 10 1.66 ( 16.28 KN/m3)

NOTE: Density requirements of Embankments and sub-grade materials as per MORTH specifications should not be less than 16 KN/m3

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UNCONFINED COMPRESSIVE STRENGTH(IS: 2720(PART 10)- 1991)

UNCONFINED COMPRESSIVE STRENGTH IN kPa

No of days of curing

0 7 28BC SOIL ONLY 220 220 220

BCS + 10% GGBS 151.2 222.8 247.9

BCS + 20% GGBS 191.6 434.2 450.8

BCS + 30% GGBS 214 1712.2 1882.2

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NOTE: Unconfined Compressive strength has increased up to 8 times that of ordinary Black Cotton Soil.

STRENGTH VARIATION ON ADDITION OF GGBS

0

200

400

600

800

1000

1200

1400

1600

1800

2000

0 7 28

UCC

STR

ENG

TH IN

KPa

NO. OF DAYS OF CURING

0% GGBS10% GGBS20% GGBS30% GGBS

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CBR VALUES (IS:2720(PART 16)-1987)

GGBS CBR (%)

0% 2.36

10% 2.67

20% 4.72

30% 14.96

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CBR VALUES

2.36 2.67

4.72

14.96

0

2

4

6

8

10

12

14

16

0 10 20 30

CB

R(%

)

PERCENTAGE OF GGBS24

COST ANALYSIS

Pavement thickness 795 mm 475 mm

Semi dense bituminous concrete 25 mm 25 mm

Dense bituminous concrete 70 mm 50 mmGranular base 250 mm 250 mmGranular sub-base 450 mm 150 mmEstimated cost Rs 62,35,706.2 Rs 53,49,281.2

Assumptions:• N= 5 msa• Width of

subgrade=7.5m• Carriage width =3.75m• Road length = 1 km

WITHOUT USING GGBS

USING GGBS (30%)

It is apparent that there is 14 % savings by using GGBS.

PAVEMENT COMPOSITION

CONCLUSION MDD increased while OMC decreased with

addition of GGBS to the soil. There is significant reduction in the swelling

behaviour of the soil. UCS has increased up to 8 times that of ordinary

Black Cotton Soil by adding 30% GGBS. CBR value has increased up to 7 times that of

ordinary Black Cotton Soil by adding 30% GGBS. The blended soil meets the requirements as per

MORTH specifications of subgrade. Hence GGBS can be used for the stabilization of

Black Cotton Soil as it has significantly improved the geotechnical properties of Black Cotton Soil.

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REFERENCES[1]. GyanenTakhelmayum1, savitha.A.L2, Krishna Gudi GSS Institute of Technology,

VTU “Experimental Studies on Soil Stabilization Using Fine and Coarse GGBS”, ISSN

2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 3, March 2013

[2]. Laxmikant Yadu and Dr. R.K. Tripathi “Effects of Granulated Blast Furnace Slag in

the Engineering Behavior of Stabilized Soft Soil", Chemical, Civil and Mechanically

Engineering tracks of third Nirma University International Conference, Procedia

Engineering 51 (2013)125-131.

[3]. K.V. Manjunath, Himanshu Shekhar, Manish Kumar, Prem Kumar and Rakesh Kumar

“Stabilization of Black Cotton Soil Using Ground Granulated Blast Furnace Slag”,

Proceedings of International Conference on Advances in Architecture and Civil

Engineering (AARCV 2012), 21st - 23rd June 2012 387 Paper ID GET114, Vol. 1

[4].IS:2720 (PART-4)-1985, Methods of test for soils: Part 4 Grain size analysis (Second

Revisions).

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REFERENCES[5].IS:2720 (PART-5)-1985, Methods of test for soils: Part 5 Determination of

liquid limit and Plastic limit (Second revision).

[6].IS:27270 (PART-8)-1983, Methods of test for soils: Part 8 Determination of

water content-dry density relation using heavy compaction (Second Revision).

[7].IS:2720 (Part-10)-1973, Methods of test for soils: Part 10 Determination of

Unconfined compressive strength (First Revision).

[8].IS:2720 (Part -16)-1979, Methods of test for soils: Part 16 Laboratory

determination of CBR. (First revision).

[9].IS:2720 (Part -40)-1977, Methods of test for soils: Part 40 Determination of

free swelling index of soils.

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