Introduction:

Expansive soil causes serious problem on civil engineering structures due to its tendency of swelling when it is in contact with water and shrinks when they dry out. Soil stabilization using chemical admixtures is the oldest and popular method of ground improvement. In this study, the potential of marble dust (by-product of marble industry) as stabilizing additive to expansive soil is evaluated. The evaluation involves the determination of the swelling potential of expansive soil in its natural state as well as when mixed with varying proportion of marble dust (from 0 to 30%). The marble dust in experimental program is obtained from cutting of Makrana marble. The environmental degradation due to marble mining is much less than the environmental degradation caused by the waste from marble processing plants.

Many researchers have reported that marble has very high lime (CaO) content up to 55% by weight. Thus, stabilization characteristics of Makrana marble dust are mainly due to its high lime content. Marble dust finds bulk utilization in roads, embankment and soil treatment for foundation. Particle size distribution, consistency limits, specific gravity, swelling percentage, and rate of swell were determined for the samples. Addition of marble dust decreases liquid limit, plasticity index and shrinkage index, increase plastic limit and shrinkage limit.

Fly ash is a fine, glass powder recovered from the gases of burning coal during the production of electricity. These micron-sized earth elements consist primarily of silica, alumina and iron. When mixed with lime and water the fly ash forms a cementitious compound with properties very similar to that of Portland cement. Because of this similarity, fly ash can be used to replace a portion of cement in the concrete, providing some distinct quality advantages. The concrete is denser resulting in a tighter, smoother surface with less bleeding. Fly ash concrete offers a distinct architectural benefit with improved textural consistency and sharper detail. Fly Ash is also known as Coal Ash, Pulverized Flue Ash, and Pozzolona. Fly ash closely resembles volcanic ashes used in production of the earliest known hydraulic cements about 2,300 years ago. Those cements were made near the small Italian town of Pozzuoli - which later gave its name to the term "pozzolan." A pozzolan is a siliceous or siliceous / aluminous material that, when mixed with lime and water, forms a cementitious compound. Fly ash is the best known, and one of the most commonly used, pozzolans in the world.

Currently, over 20 million metric tons (22 million tons) of fly ash are used annually in a variety of engineering applications. Typical highway engineering applications include: Portland cement concrete (PCC), soil and road base stabilization, flowable fills, grouts, structural fill and asphalt filler. Fly ash is most commonly used as a pozzolan in PCC applications.

Lime in the form of quicklime (calcium oxide – CaO), hydrated lime (calcium hydroxide – Ca [OH] ₂), or lime slurry can be used to treat soils. Quicklime is manufactured by chemically transforming calcium carbonate (limestone – CaCO₃) into calcium oxide. Hydrated lime is created when quicklime chemically reacts with water. It is hydrated lime that reacts with clay particles and permanently transforms them into a strong cementitious matrix. Most lime used for soil treatment is “high calcium” lime, which contains no more than 5 percent magnesium oxide or hydroxide. On some occasions, however, "dolomitic" lime is used. Dolomitic lime contains 35 to 46 percent magnesium oxide or hydroxide. Dolomitic lime can perform well in soil stabilization, although the magnesium fraction reacts more slowly than the calcium fraction. Sometimes the term “lime” is used to describe agricultural lime which is generally finely ground limestone, a useful soil amendment but not chemically active enough to lead to soil stabilization. “Lime” is also sometimes used to describe byproducts of the lime manufacturing process (such as lime kiln dust), which, although they contain some reactive lime, generally have only a fraction of the oxide or hydroxide content of the manufactured product. In this manual, “lime” means quicklime, hydrated lime, or hydrated lime slurry.

LITERATURE REVIEW:

Kameshwar Rao Tallapragada et al (2009):

From the detailed laboratory investigations on black-cotton soil with monofilament and nylon threads as reinforcing materials, graphs are plotted between various soil properties and various physical parameters (thickness, length to diameter ratio, percentage weight of fibers) of reinforcing material. The CBR value increases with increase in percentage of fibers but it remains almost same after 2.25%. Also the Nylon thread seems to give better results in terms of CBR compared to monofilament. There is considerable decrease in cohesion of soil with monofilament whereas it is marginal with nylon thread. Though F value increase with addition of both the reinforcing materials. Unconfined compressive strength of the soil increases with the addition of both monofilaments and nylon threads, but seems to be better with nylon threads. Swelling pressure of the soil decreases with the addition of both the materials, but there is a marginal difference when change in swelling pressure is compared. There is negligible change in CBR, UCS, F value, C value and Swelling pressure as the Aspect ratio increases. The above points of conclusion reveals that nylon thread of 1.6 mm thick and 2.25% weight of all the aspect ratios gives better results as compare to monofilament as far as improvement in various desirable soil properties are concerned.

Akshaya Kumar Sabat (2012):

"Effect of Polypropylene Fiber on Engineering Properties of Rice Husk Ash – Lime Stabilized Expansive Soil" The addition of rice husk ash and lime decreases the swelling pressure of expansive soil. The swelling pressure goes on decreasing, with increase in percentage of addition of polypropylene fiber in rice husk ash-lime stabilized expansive soil. The swelling pressure decreases with increase in curing period irrespective of the percentage of addition of polypropylene fiber in rice husk ash-lime stabilized expansive soil. The optimum proportion of Expansive soil: Rice husk ash: Lime: Polypropylene Fiber is found to be 84.5:10:4:1.5.

H. P. Singh, et al, (2013):

In this study the percentage of Jute fiber by dry weight of soil was taken as 0.25%, 0.5%, 0.75% and 1%. In the present investigation the lengths of fiber was taken as 30 mm, 60 mm and 90 mm and two different diameters, 1 mm and 2 mm were considered for each fiber length. Tests result indicates that CBR value of soil increases with the increase in fiber content. Thus there is significant increase in CBR value of soil reinforced with Jute fiber and this increase in CBR value will substantially reduce the thickness of pavement sub grade.

S. K. Shukla, N. Sivakugan and A. K. Singh:

A simple force-equilibrium model is proposed for predicting the behavior of fiber-reinforced granular soils under high confining stresses considering several important soil and fiber parameters, such as fiber content, aspect ratio, modulus of elasticity of fibers, specific gravity of fiber material, skin friction, initial orientation with respect to shear plane, confining stress, specific gravity of soil particles, angle of shearing resistance of soil, and void ratio of soil; The expression shows that the apparent cohesion and increase in normal confining stress due to fibers are proportional to the fiber content and aspect ratio implying that the shear strength increase is also proportional to the fiber content and aspect ratio. For a specific range of parameters, it is observed that the increase in shear strength of the granular soil due to fibers is mainly from the apparent cohesion, and the contribution to the shear strength from the increase in normal confining stress is limited. The model predicts well many special cases, and the trends of variation of the SSR, defined as the shear strength of reinforced soil to that of unreinforced soil, follow the trends of variation as observed in the experimental studies reported in literature and Since the parameters as required in the proposed model are not reported in the existing experimental studies, it would be interesting to have experimental data, preferably based on large-scale tests to develop better understanding of the present model.

METHODOLOGY:

Materials used:

1 Soil:- Collected from Renukavihar Colony Beltarodi Road, Nagpur

2 Fly Ash:- Collected from KTPS, Nagpur

3 Lime:- Available in market, Nagpur

4 Nylon fiber:- Available in the market

SOIL PROPERTIES:

Based on the experiments (Grain size analysis, liquid limit, plastic limit, specific gravity, standard proctor test and CBR test), the following soil properties are obtained and presented in a tabulated form.

Soil properties
Sr. No.	Laboratory Test	Result
1	Liquid Limit	48.5 %
2	Plastic Limit	34.29%
3	Plasticity Index	14.21%
4	Soil Classification	MH and OH
5	Particle size distribution	75% Fine particles, 25% Coarse particles
6	Specific Gravity	2.58
7	O.M.C.	22.65 %
8	M.D.D.	1.65 gm/cc
9	Angle of internal friction (ϕ )	17 degree
10	Cohesion (C)	0.89 kg /sq. cm.
11	C.B.R.	3.64 %

Soaked CBR on (soil + fly ash + lime sample)

Sr. No.	Penetration (mm)	Load ( kg)
1	0	0
2	0.5	30.72
3	1	73.6
4	1.5	120.32
5	2	186.88
6	2.5	251.2
7	3	282.88
8	4	368
9	5	395.52
10	7.5	426.24
11	10	468.48
12	12.5	524.8

Sr. no.	Penetration(mm)	CBR (%)
1	2.5 mm	16.63
2	5.0 mm	15.88
CBR of soil =16.63%

AVERAGE SOAKED CBR READING (WITH NYLON FIBER OF LENGTH (1cm)

Proportion:- soil, fly ash (50:50) with 6% lime and 0.05% Nylon fiber

Table: CBR on (soil + fly ash + lime) with 0.05% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	32
3	1	90.24
4	1.5	155.52
5	2	199.04
6	2.5	252.16
7	3	276.48
8	4	328.32
9	5	377.6
10	7.5	403.84
11	10	443.52
12	12.5	487.04

Sr. no.	PENETRATION	CBR (%)
1	2.5 mm	18.41
2	5.0 mm	18.37
CBR of soil =18.41

Proportion:- soil, fly ash (50:50) with % lime and 0.10% Nylon fiber

Table : CBR on (soil + fly ash + lime) with 0.10% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	44.8
3	1	110.72
4	1.5	168.32
5	2	250.88
6	2.5	302.72
7	3	359.68
8	4	417.6
9	5	448.64
10	7.5	528
11	10	570.24
12	12.5	648.32

Sr. No.	PENETRATION	CBR (%)
1	2.5 mm	22.10
2	5.0 mm	21.83
CBR of soil =22.10

Proportion:- soil, fly ash (50:50) with % lime and 0.15% Nylon fiber

Table : CBR on (soil + fly ash + lime) with 0.15% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	51.2
3	1	122.88
4	1.5	179.2
5	2	263.68
6	2.5	318.72
7	3	378.24
8	4	436.48
9	5	463.36
10	7.5	550.4
11	10	590.72
12	12.5	674.56

Sr. no.	PENETRATION	CBR (%)
1	2.5 mm	23.26
2	5.0 mm	22.55
CBR of soil =23.26

Proportion:- soil, fly ash (50:50) with % lime and 0.20% Nylon fiber

Table : CBR on (soil + fly ash + lime) with 0.20% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	44.8
3	1	115.2
4	1.5	200.32
5	2	275.2
6	2.5	328.96
7	3	378.24
8	4	436.48
9	5	488.96
10	7.5	550.4
11	10	590.72
12	12.5	674.56

Sr. no.	PENETRATION	CBR (%)
1	2.5 mm	24.01
2	5.0 mm	23.79
CBR of soil =24.01

AVERAGE SOAKED CBR READING (WITH NYLON FIBER OF LENGTH (2cm )

Proportion :- soil, fly ash (50:50) with % lime and 0.05% Nylon fiber

Table: CBR on (soil + fly ash + lime) with 0.05% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	15.36
3	1	52.48
4	1.5	103.04
5	2	161.92
6	2.5	230.4
7	3	251.52
8	4	283.52
9	5	332.8
10	7.5	407.68
11	10	424.32
12	12.5	467.84

Sr. no.	PENETRATION	CBR (%)
1	2.5 mm	19.20
2	5.0 mm	19.03
CBR of soil =19.20

Proportion:- Soil, fly ash (50:50) with % lime and 0.10% Nylon fiber

Table : CBR on (soil + fly ash + lime) with 0.10% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	15.36
3	1	52.48
4	1.5	103.04
5	2	161.92
6	2.5	230.4
7	3	251.52
8	4	283.52
9	5	332.8
10	7.5	407.68
11	10	424.32
12	12.5	467.84

Sr. no.	PENETRATION	CBR (%)
1	2.5 mm	23.31
2	5.0 mm	22.58
CBR of soil =23.31

Proportion: soil, fly ash (50:50) with % lime and 0.15% Nylon fiber

Table: CBR on (soil + fly ash + lime) with 0.15% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	15.36
3	1	52.48
4	1.5	103.04
5	2	161.92
6	2.5	230.4
7	3	251.52
8	4	283.52
9	5	332.8
10	7.5	407.68
11	10	424.32
12	12.5	467.84

Sr. no.	PENETRATION	CBR (%)
1	2.5 mm	24.85
2	5.0 mm	23.73
CBR of soil =24.85

Proportion:- soil, fly ash (50:50) with % lime and 0.20% Nylon fiber

Table: CBR on (soil + fly ash + lime) with 0.20% Nylon fiber

SR. NO.	PENETRATION (mm)	LOAD ( kg)
1	0	0
2	0.5	15.36
3	1	52.48
4	1.5	103.04
5	2	161.92
6	2.5	230.4
7	3	251.52
8	4	283.52
9	5	332.8
10	7.5	407.68
11	10	424.32
12	12.5	467.84

RESULTS:

For all the Average soaked CBR reading of soil, fly ash (50:50) with 6 % lime and different proportion and length Nylon fiber charts are prepared and represented in tabulated and graphical form –

Table: - CBR Comparison chart different proportion and length of nylon fiber

Sr.No.	Size (cm)	Proportion %	CBR 2.5 mm %	CBR 5 mm %
1	1	0.05	18.41	18.37
		0.1	22.1	21.83
		0.15	23.26	22.55
		0.2	24.01	22.55
2	2	0.05	19.2	19.03
		0.1	23.31	22.58
		0.15	24.85	23.73
		0.2	25.69	24.04

CBR Comparison chart different proportion of nylon fiber length 1cm

CBR Comparison chart different proportion of Nylon fiber size 2cm

DISCUSSION AND CONCLUSION:

Effect of nylon fiber:

1. Soaked C.B.R. test by using Nylon fiber of 1.0 cm length and in different proportions i.e. 0.05 % , 0.10%, 0.15% and 0.02%. The CBR observed that 18.41%, 22.10%, 23.26 % and 24.01% respectively. The above result shows that as the %age of nylon fiber increases from 0.05% to 0.2% CBR value also increases accordingly.

2. Soaked C.B.R. test by using Nylon fiber of 2.0 cm length and in different proportions i.e. 0.05 %, 0.10%, 0.15% and 0.02%. The CBRobserved that 19.20%, 23.31%, 24.85 % and 25.69% respectively. The above result shows that as the %age of nylon fiber increases from 0.05% to 0.20% CBR value also increases accordingly.

3. The above observation leads to the conclusion that the most feasible and efficient sample for soil stabilization is fly ash with 2.0 cm length nylon fiber at 2.0% proportion.

4. Hence, Using Fly ash with nylon fiber potentially stabilizes the soil and is the feasible and environment friendly method to stabilize the soil in the construction process of road and buildings by using the industrial waste fly ash whose disposal otherwise is the biggest challenge for the industries and environment.

References:

1 Pandian, N.S., Krishna, K.C., and Sridharan, A. (2001) “California bearing ratio behavior of soil/fly ash mixtures,” Journal of Testing and Evaluation, ASTM, Vol. 29,No. 2, pp 220–226.

2 Puppala, A.J., and Musenda, C. (2000) “Effect of fiber reinforcement on strength and volume change behavior of two expansive soils,” Transportation Research Record: Journal of the Transportation Research Board, Vol. 1736, pp 134‐140.

3 Ramesh, H.N., Manoj Krishna, K.V., and Mamatha, H.V. (2010) “Compaction and strength behavior of lime-coir fiber treated Black Cotton soil,” Geomechanics and Engineering, Vol. 2, No.1, pp 19-28.

4 Sabat, A.K.(2012) “A study on some geotechnical properties of lime stabilised expansive soil –quarry dust mixes,” International Journal of emerging trends in engineering and development ,Vol. 1, Issue.2, pp 42-49.

5 Sharma, R.S. PhaniKumar, B.R., and Rao, B.V. (2008) “Engineering behaviour of a remolded expansive clay blended with lime, calcium chloride and Rice- husk ash,”Journal of materials in civil engineering, ASCE , Vol.20, No.8, pp 509-515.

6 ÇokÇa E. (2001): Use of class C fly ashes for the stabilization of an expansive soil. Journal of Geotechnical and Geoenvironmental Engineering, Vol. 127, No. 7, pp. 568-573.

7 Phanikumar B.R. et al (2004) “Effect of Flyash on engineering properties of Expansive soils.” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol.130, 764-767.

8 S. Bhuvaneshwari et al (2005) “Stabilization of Expansive Soils using Flyash.” Proceeding of Flyash India 2005, VIII 5.1-5.10.

9 Mishra, A.K., Dhawan S., Rao, S.M., Analysis of Swelling and Shrinkage Behavior of Compacted Clays, Geotechnical and Geological Engineering, Vol. 26, No. 3, pp. 289-298, 2008.

10 Jones, D. E., and Holtz, W. G., Expansive Soils - the hidden disaster, Civil Engineering, ASCE 43(8), pp. 49-51, 1973.

11 Al-Rawas, A.A., Taha R., Nelson, J.D., Al-Shab, T.B. and Al-Siyabi, H.,A Comparative Evaluation of Various Additives Used in the Stabilization of Expansive Soils, Geotechnical Testing Journal, Vol. 25, No. 2, pp. 199-209, 2002.

12 Wayne, A.C., Mohamed, A.O. and El-Fatih, M.A., Construction on Expansive Soils in Sudan, Journal of Construction Engineering and Management, Vol. 110, No. 3, pp. 359-374, 1984.

13 Terzaghi, K., Peak R.B. and Mesri, G., Soil Mechanics in Engineering Practice, 3rd Edition, John Wiley and Sons Inc., New York, 1996.

14 Mitchell, J. K., Fundamentals of Soil Behavior, John Wiley and Sons Inc., New York, 1976.

15 Mitchell, J. K., Fundamentals of Soil Behavior, John Wiley and Sons Inc., New York, 1976.

16 Oweis, I. S., Khera, R. P., Geotechnology of Waste Management, 2^nd Edition, PWS Publishing Company, Boston, 1998.

17 Nelson, J.D. and Miller, D.J., Expansive Soils, Problems and Practice in Foundation and Pavement Engineering, John Wiley and Sons Inc., New York, 1992.

Received on 06.10.2015 Modified on 17.10.2015

Research J. Science and Tech. 7(4):Oct. – Dec. 2015; Page 217-222

DOI: 10.5958/2349-2988.2015.00031.5