EXPERIMENTAL INVESTIGATION ON CALIFORNIA BEARING RATIO FOR MECHANICALLY STABILIZED EXPANSIVE SOIL USING WASTE RUBBER TYRE CHIPS

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 6, Issue 11, Nov 2015, pp , Article ID: IJCIET_06_11_011 Available online at ISSN Print: and ISSN Online: IAEME Publication EXPERIMENTAL INVESTIGATION ON CALIFORNIA BEARING RATIO FOR MECHANICALLY STABILIZED EXPANSIVE SOIL USING WASTE RUBBER TYRE CHIPS Phani Kumar Vaddi Assistant Professor, Dept. of Civil Engineering, Gudlavalleru Engineering College, Gudlavalleru, Krishna Dt, A. P D. Ganga Assistant Professor, Dept. of Civil Engineering, Gudlavalleru Engineering College, Gudlavalleru, Krishna Dt, A. P P. Swathi Priyadarsini Assistant Professor, Dept. of Civil Engineering, Gudlavalleru Engineering College, Gudlavalleru, Krishna Dt, A. P Ch. Naga Bharath Assistant Professor, Dept. of Civil Engineering, Gudlavalleru Engineering College, Gudlavalleru, Krishna Dt, A. P ABSTRACT Soil stabilization is any process which improves the physical properties of soil, such as increasing shear strength, bearing capacity etc. which can be done by use of controlled compaction or addition of suitable admixtures like cement, lime and waste materials like phosphogypsum, etc. The cost of introducing these additives has also increased in recent years which opened the door widely for the development of other kinds of soil additives such as plastics, bamboo, fly ash etc. This new technique of soil stabilization can be effectively used to meet the challenges of society, to reduce the quantities of waste, producing useful material from non-useful waste materials. This paper involves the detailed study on the possible use of waste rubber tyre chips and lime for soil stabilization. The analysis was done by conducting wet sieve analysis, compaction test and CBR by replacing the soil with lime and waste rubber tyre chips. The optimum percentage of waste rubber tyre chips and lime in soil was found out by California Bearing Ratio Test. The 97 editor@iaeme.com

2 Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath amount of waste rubber tyre chips has significant effect on the enhancement of strength of the soil. Many methods exist today, which utilize mainly CBR test values for designing pavement thickness requirement. Inorder to decrease the thickness of pavement we are going to increase the CBR value by stabilizing the soil with waste materials like lime and waste rubber tyre chips, which decreases the cost of laying of pavements. From the results of this paper the CBR values are increasing with increase in the replacement of soil with lime and waste rubber tyre chips up to certain limit and there after decreases. The percentage at which the maximum value of CBR is obtained is known as Optimum percentage of lime and waste rubber tyre chips. The optimum percentage of lime is 4% and the optimum percentage waste rubber tyre chips is 6%. Key words: Compaction, CBR, Liquid Limit, Plasticity Index, Expansive Soil and Waste Rubber Tyre. Cite this Article: Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath, Experimental Investigation On California Bearing Ratio For Mechanically Stabilized Expansive Soil Using Waste Rubber Tyre Chips. International Journal of Civil Engineering and Technology, 6(11), 2015, pp INTRODUCTION Lime was widely used in the 1970s and 1980s for soil stabilization in the construction of many of Belgium s motorways. Nowadays, the use of lime to improve the characteristics of silt and clay soils is still in full development. The addition of lime to improve the strength and other desirable properties of soil is not a new technology. It s earliest documented use can be traced back to Roman times, when lime was used to construct the Appian Way. The technology became more prevalent in the early 20th century, when the growth in motorized vehicles created the need for more stable, longer lasting roadways. At that time, bagged hydrated lime was mixed into the soil using farm equipment (disking operations). This practiced continued through the early days of Interstate highway construction in the U.S. Solid waste management is one of the major environmental concerns worldwide. In India, the scrap tyres are being generated and accumulated in large volumes causing an increasing threat to the environment. In order to eliminate the negative effect of these depositions and in terms of sustainable development, there is great interest in the recycling of these non-hazardous solid wastes. The potential of using rubber from worn tyres in many civil engineering works has been studied for more than 30 years. Applications where tyres can be used have proven to be effective in protecting the environment and conserving natural resources. In recent times with the increase in the demand for infrastructure and feasible foundation design in not applicable due to poor bearing capacity of ground soil stabilization has started to take a new shape editor@iaeme.com

3 Experimental Investigation On California Bearing Ratio For Mechanically Stabilized Expansive Soil Using Waste Rubber Tyre Chips 2. EXPERIMENTAL INVESTIGATIONS 2.1. Materials used Soil The soil used in the present investigation, is obtained from the place near Gudlavalleru, Krishna district. The required amount of soil is collected from the trial pits at a depth of 2m below the ground level, since the top soil is likely to contain organic matter and other foreign materials. Sufficient care has been taken to see that the collected soil sample is fairly homogeneous. The soil so obtained is air dried, crushed with wooden mallet and passed through 4.75mm sieve. This soil so obtained is kept in polythene bags for further testing. The index properties of the soil are given in the Table 1. The soil is classified as CH as per I.S. classification (I.S. 1498:1970) indicating that it is clay of high plasticity. Table 1 Properties of the Untreated Soil S.No. Property Soil 1 Gravel % 0 2 Sand % 8 3 Silt + Clay % 92 4 Liquid limit % Plastic limit % Plasticity index % 45 7 Differential free swell index % IS Classification CH 9 Maximum dry density KN/m Optimum moisture content % C.B.R% Specific Gravity Lime Lime used in this investigation, has been obtained from the stores, which is located at Kakinada, Andhra Pradesh, India. The Chemical Composition of lime is presented in Table2. TABLE 2 Chemical Composition of the Lime Property Value Cao 91% Mgo 7% Rubber Tyre Chips The waste Rubber Tyre Chips are obtained from Auto Nagar in Gudivada, Krishna district. The waste Rubber Tyre Chips, added to the soil was considered a part of the solid fraction in the void solid matrix of the soil. The content of the waste Rubber Tyre Chips are defined here in as the ratio of weight of plastic to the weight of dry Expansive Soil. The tests were conducted at various waste Rubber Tyre Chips contents of 2%, 4%, 6%, 8% and 10% editor@iaeme.com

4 Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath 3. PROCEDURE FOR MIXING In order to meet the objectives of the present investigation a total of three series of tests are conducted on soils as given below First Series of Tests The first series of tests are aimed at studying the classification, compaction and CBR behaviour of Expansive Soil in natural conditions. Table 3 gives the various types of tests which are conducted for soil in laboratory. Table 3 Details of 1 st series of tests conducted S.No. Type of Soil Tests conducted 1. Expansive Soil Atterberg Limits, Wet sieve analysis, Differential Free Swell Index, Light Compaction test and CBR TEST 3.2. Second Series of Tests (Determination of Optimum Lime) The second series of tests are aimed at determining Optimum Lime from the view point of compaction characteristics and CBR characteristics. Lime is mixed with the Expansive soil in different proportions and tests are conducted as per the details presented in Table 4. Table 4 Details of 2 nd series of tests conducted S.No. Soil mixtures Tests conducted 1. Expansive soil +2%Lime 2. Expansive soil +4%Lime 3. Expansive soil +6%Lime Compaction test and CBR test Third Series of Tests (Influence of optimum Waste Rubber Tyre Chips) The third series of tests are aimed at studying the influence of optimum waste Rubber Tyre Chips on compaction and CBR behaviour of Expansive Soils treated with optimum Lime. The optimum Lime obtained from second series of tests is used in this series of tests and the tests are conducted on those soils with various proportions of waste Rubber Tyre Chips. All the tests were conducted after addition of waste Rubber Tyre Chips. The details of third series of tests conducted are shown in Table 5. Table 5 Details of 3 rd series of tests conducted S.No. Soil mixture % waste Rubber Tyre Chips added Tests conducted Expansive Soil Optimum Lime Compaction Test and CBR test editor@iaeme.com

5 Experimental Investigation On California Bearing Ratio For Mechanically Stabilized Expansive Soil Using Waste Rubber Tyre Chips 4. TESTS CONDUCTED ON TREATED SOIL The following tests have been conducted in this investigation Wet Sieve Analysis The soil sample is soaked in a bucket of water for 2 to 3 hours, after that the sample is taken into 4.75mm sieve and it is placed under the pump or tap with forced water then the sample retained on 4.75mm sieve is taken out and placed it in an oven for drying, after that we have to done the Grain Size Analysis as per IS part IV (1985). Based on those results we can classify the soil Liquid Limit This test is conducted as per IS 2720 (Part V) Brief description of the test procedure is given below. An air dried soil sample (about 250 g) passing the 425 micron sieve is mixed with distilled water. The soil sample is filled in the metal cup and the surface struck off level. The cone is lowered to just touch the surface of soil and then released for a period of 5 seconds. The penetration is measured. The cone is lifted and cleaned and the depression in the soil surface is filled up by adding a little more wet soil. The test is repeated. If the difference between the two measured penetrations is less than 0.5 mm, the tests are considered valid. The average penetration is noted and the moisture content of the soil is determined. The test is repeated at least 4 times with increasing moisture contents. The moisture contents used inthe tests should be such that the penetrations obtained lie within a range of 15 to 35 mm Plastic limit Air-dried soil samples have been used for this test. The soil fraction passing the 425µ sieve is taken for the test. About 30gm of soil is taken in an evaporating dish and thoroughly mixed with distilled water till it becomes plastic and it becomes easily moulded with fingers. About 10gm of the plastic soil mass is taken in one hand and a ball is formed. The ball is rolled with fingers on a glass plate to form a soil thread of uniform diameter of about 3mm approximately without crumbling. The rate of rolling is kept about 80 to 90 strokes / min. The test is repeated taking a fresh sample each time. The plastic limit is taken as the average of three values Plasticity index Plasticity Index is the range of water content over which the soil remains in the plastic state. It is equal to difference between the liquid limit and plastic limit. Thus Plasticity Index (Ip) = Liquid limit (L.L) Plastic limit (P.L) 4.5. Differential Free Swell Index This test is performed by pouring slowly 10 grams of dry soil passing through 425 micron sieve, in two different 100 cc glass jars filled with distilled water, kerosene. The swollen volume of expansive soil, was recorded as per IS 2720 part 40(1985). = V editor@iaeme.com

6 Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath Where V 1 = Volume of the soil specimen read from the graduated cylinder containing distilled water. V 2 = Volume of the soil specimen read from the graduated cylinder containing kerosene Standard Proctor Compaction Test This test is conducted as per IS 2720 (Part VIII) Brief description of the test procedure is given below. The Standard Proctor Mould is cleaned, dried and greased lightly. The mass of the empty mould with the base plate, but without collar, is taken. The collar is then fitted to the mould. The mould is placed on a Solid Base & filled with fully matured soil to about 1/3 rd its height. The Soil is compacted by 25 blows of the rammer with a free fall of 310mm. The blows are evenly distributed over the surface. The soil surface is scratched with a spatula before the second layer is placed. The mould is filled to about 2/3 rd height with the soil and compacted again by 25 blows. Likewise, the third layer is placed & compacted. The third layer should project above the top of the mould into the collar by not more than 6mm. The mass of the mould, base plate & the compacted soil is taken, and thus the mass of the compacted soil is determined. The Bulk Density of the soil is computed from the mass of compacted soil & the volume of the mould. Representative soil samples are taken from the bottom middle & top of the mould for determining the water content. The Dry Density is computed from the bulk density &water content. A Compaction Curve is plotted between the water content as abscissa & corresponding dry density as ordinate. The water content corresponding maximum dry density is called as Optimum Moisture Content California Bearing Ratio (CBR) Test The CBR test is conducted on soil sample prepared at O.M.C and M.D.D as per IS: 2720 Part XVI and the california bearing ratio laboratory apparatus. The load is applied by loading frame through a plunger of 50mm diameter on the specimen in the mould compacted to Maximum Dry Optimum Moisture content. Dial gauges are used for the measurement of penetration. The mixing was done manually and the CBR mould is cleaned, dried and greased lightly. The mix is placed in the mould in three layers, each layer is compacted by 25 blows of rammer with a free fall of 310mm. After compacting the third layer the mould is placed in CBR apparatus under the plunger for conducting the test. The test consists of causing the plunger to penetrate the specimen at the rate of 1.25 mm per minute. The loads required for penetration of 2.5mm & 5mm are recorded by the proving ring attached to the plunger. The Load is expressed as a percentage of Standard Load at the respective deformation level and is known as California Bearing Ratio (CBR) Value. The CBR Value is determined corresponding to both 2.5mm & 5mm Penetration and the greater value is used for design purpose. % = editor@iaeme.com

7 Experimental Investigation On California Bearing Ratio For Mechanically Stabilized Expansive Soil Using Waste Rubber Tyre Chips Penetration, mm 5. RESULTS AND DISCUSSIONS Standard load, kg FIRST SERIES (ONLY EXPANSIVE SOILS) The first Series of tests are aimed at studying the influence on compaction and California bearing ratio characteristics of expansive soil. Fig. 1 to 3 gives the test details of expansive soil. Figure 1 Liquid Limit of Expansive Soil Figure 2 Compaction Curve of Expansive Soil Figure 3 CBR Behaviour Curve of Expansive Soil editor@iaeme.com

8 Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath 5.2. SECOND SERIES (INFLUENCE OF LIME) The second Series of tests s is aimed at studying the influence of lime on compaction and California bearing ratio characteristics of expansive soils. The expansive soils are mixed with lime. Fig. 4 to 8 gives the test details on soil-lime lime mixtures. Figure 4 Compaction Curve of Expansive Soil with Lime Table 6 Optimum Moisture Content of Expansive Soil With Lime LIME (%) Optimum moisture content (%) Percent increase in Optimum moisture content Table 7 Maximum Dry Density of Expansive Soil With Lime LIME (%) Maximum Dry Density (g/cc) Percent variation in Maximum Dry Density Figure 5 Behaviour of Optimum Moisture Content with Lime editor@iaeme.com

9 Experimental Investigation On California Bearing Ratio For Mechanically Stabilized Expansive Soil Using Waste Rubber Tyre Chips Figure 6 Behaviour of Maximum Dry Density with Lime Figure 7 Variation of CBR with Lime Figure 8 Behaviour of CBR with Lime Table 8 CBR of Expansive Soil with Lime LIME (%) CBR (%) Percent variation in CBR editor@iaeme.com

10 Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath 5.3. THIRD SERIES (INFLUENCE OF RUBBER TYRE CHIPS) The third Series of tests is aimed at studying the influence of waste rubber tyre chips on compaction and California bearing ratio characteristics of expansive soils. The optimum lime obtained from second series of tests is used in this series of tests and the tests are conducted on soil on which second series of tests were conducted. Expansive soils treated with lime are mixed with rubber tyre chips in different proportions. Fig. 9 to 13 gives the test details of rubber tyre chips. Figure 9 Compaction Curve of Expansive Soil with Optimum Lime and Waste Rubber Tyre Chips Table 9 Optimum Moisture Content of Expansive Soil With Optimum Lime And Waste Rubber Tyre Chips Waste rubber tyre chips (%) Optimum moisture content (%) Percent decrease in Optimum moisture content Table 10 Maximum Dry Density of Expansive Soil With Optimum Lime And Waste Rubber Tyre Chips LIME (%) Maximum Dry Density (g/cc) Percent increase in Maximum Dry Density editor@iaeme.com

11 Experimental Investigation On California Bearing Ratio For Mechanically Stabilized Expansive Soil Using Waste Rubber Tyre Chips Figure 10 Behaviour of Optimum Moisture Content with Rubber Tyre Chips Figure 11 Behaviour of Maximum Dry Density with with Rubber Tyre Chips Figure 12 Variation of CBR with Rubber Tyre Chips

12 Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath Figure 13 Behaviour of CBR with Rubber Tyre Chips Table 11 CBR Of Expansive Soil with Optimum Lime and Waste Rubber Tyre Chips LIME (%) CBR (%) Percent increase in CBR SUMMARY AND CONCLUSIONS 6.1. Summary Expansive soils also called swelling soils are prone to volume changes corresponding to change in moisture content. Expansive soils have been reported from many parts of the World, mainly in the arid or semi arid regions of the tropical and temperate zones like Africa, Australia, India, South America, United States and some regions in Canada. In India, swelling soils are commonly known as Black Cotton soils. About one-fifth of the land area in India is covered by these soils. Because of the alternate Swelling and Shrinkage, lightly loaded structures such as foundations, pavements, canal linings and residential ial buildings founded on them are severely damaged. Design and construction of Civil Engineering structures on and with expansive soils is a challenging task for civil Engineers. Several investigations were carried out in India and World wide to stabilize expansive soils using different additives like Cement, Lime, Calcium chloride and industrial wastes etc. The soil used is obtained from the place near Gudlavalleru, Krishna district. The required amount of soil is collected from the trial pits at a depth of 2m below the ground level. The soil is classified as CH as per Indian standard ard soil classification system. Its Differential Free Swelling Index is % which indicates that it is highly expansive in nature. Limits, Wet sieve analysis, alysis, Differential Free Swell Index, Light Compaction test and CBR test, second series of test for expansive mixed with lime at 2%, 4% and 6% are Compaction test and CBR test and third series of tests for expansive soil optimum lime and waste rubber tyre chips at 2%, 4%, 6%, 8% and 10% are Compaction test and CBR test. The soil used in this investigation is CH. It is highly expansive soil in nature as the Differential Free Swelling Index is % editor@iaeme.com

13 Experimental Investigation On California Bearing Ratio For Mechanically Stabilized Expansive Soil Using Waste Rubber Tyre Chips 6.2 Conclusions Compaction, California bearing ratio characteristics of expansive soil are dependent on clay content present in the soil. The MDD and CBR values for the expansive soil are low when compared to the lime and rubber tyre chips. OMC in general increases with increasing the replacement of lime. MDD decreases with increasing the lime. Lime stabilization increases the CBR, the optimum % of lime at which we got this result is 4%. OMC in general decreases with increasing the replacement of rubber tyre chips at optimum lime content. MDD increases with increasing the replacement of rubber tyre chips at optimum lime content Rubber tyre chips stabilization increases the CBR value. The optimum % of lime and % of rubber tyre chips at which we got this result is 6%. Thus this project is to meets the challenges of society to reduce the quantities of wastes, producing useful material from non-useful waste materials that lead to the foundation of sustainable society. REFERENCES [1] J. Antonio H. Carraro, Ethan P. Wiechert, Jesse Dunham-Friel Beneficial Use of Off-Specification Fly Ash to Improve the Small-Strain Stiffness of Expansive Soil-Rubber Mixtures. World of Coal Ash(WOCA) conference, May 9-12, [2] IS: 2720-Part XVI (1987) Laboratory determination of CBR, Bureau of Indian Standard, New Delhi, India. [3] Arora, K. R. (2004). Soil Mechanics and Foundation Engineering. Standard Publishers Distributors. [4] Meei-Hoan Ho The Potential of Using Rubberchips as a Soft Clay Stabilizer Enhancing Agent Canadian Center of Science and Education, ISSN , Vol. 4, No. 10, October 2010, PP [5] Amin EsmaeilRamaji A Review on the Soil Stabilization Using Low-Cost Methods Journal of Applied Sciences Research, ISSN X, 8(4), 2012, PP [6] Moayyad Al-Nasra, ZeljkoTorbica Concrete Made for Energy Conservation Using Recycled Rubber Aggregates International Journal of Engineering Science Invention, ISSN (Online): , ISSN (Print): , Volume 2 Issue 9, September. 2013, PP [7] IS part V (1985), Determination of Liquid and plastic limit, BIS, New Delhi. [8] Shiva Prasad. A, P. T. Ravichandran, R. Annadurai, P. R. Kannan Rajkumar Study on Effect of Crumb Rubber on Behavior of Soil International Journal of Geomatics and Geosciences ISSN , Volume 4, No 3, 2014, PP [9] Monica Malhotra, Sanjeev Naval Stabilization of Expansive Soils Using Low Cost Materials ISSN: , Volume 2, Issue 11, May 2013, PP [10] IS: 2720-Part VIII(1983) Laboratory determination of compaction, Bureau of Indian Standard, New Delhi, India. [11] IS: 2720-Part IV(1983) Laboratory determination of Grain size analysis, Bureau of Indian Standard, New Delhi, India editor@iaeme.com

14 Phani Kumar Vaddi, D. Ganga, P. Swathi Priyadarsini and Ch. Naga Bharath [12] Chen F.H (1975). Foundations on Expansive soils. Elsevier Scientific pub co., Amsterdam. [13] GhatgeSandeepHambirao, Dr. P.G. Rakaraddi Soil Stabilization Using Waste Shredded Rubber Tyre Chips IOSR Journal of Mechanical and Civil Engineering, e-issn: , p-issn: X, Volume 11, Issue 1, Feb. 2014, PP [14] IS: 2720-Part XXXX (1977) Laboratory determination Differential Free Swell Index, Bureau of Indian Standard, New Delhi, India [15] Dr. K. V. Krishna Reddy, Stabilization of Medium Plastic Clays Using Industrial wastes, International Journal of Civil Engineering and Technology, Volume 4, Issue 3, May June, 2013, PP