International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 11, November 2018, pp. 1236 1243, Article ID: IJCIET_09_11_120 Available online at http://www.iaeme.com/ijciet/issues.asp?jtype=ijciet&vtype=9&itype=11 ISSN Print: 0976-6308 and ISSN Online: 0976-6316 IAEME PublicationScopus Indexed A STUDY ON SOIL STABILIZATION USING CEMENT AND FLY ASH Diana Alice Sugunan, G.Balamurali and S.Muthulakshmi Department Of Civil Engineering, PSNA College of Engineering and Technology, Dindigul, India ABSTRACT Improvement of soil in foundation is a major challenge in Civil Engineering. Structures built on black cotton soils may be damaged due to high swelling and shrinkage characteristics of this soil with variation of water content. Black cotton soil is an expansive soil which loses its strength in presence of water. The soil properties can be improved by using methods such as mechanical stabilization, chemical stabilization, grouting using geotextiles, using admixtures etc. The present paper is an attempt to study the effectiveness of cement and fly-ash as an admixture to improve the strength and durability of black cotton soil along with an impact on its dry density. The test results show that the presence of 50% cement, the shrinkage limit is increases by 8.75% to 11.02% when compared to 50% of fly-ash in black cotton soil. Keywords: Black cotton soil, Admixtures, Strength, Shrinkage limit. Cite this Article: Diana Alice Sugunan, G.Balamurali and S.Muthulakshmi, Study on Soil Stabilization Using Cement and Fly Ash, International Journal of Civil Engineering and Technology, 9(11), 2018, pp. 1236 1243. http://www.iaeme.com/ijciet/issues.asp?jtype=ijciet&vtype=9&itype=11 1. INTRODUCTION Black cotton soils covers approximately 20% of land area in India and are predominant in the states present in Deccan Plateau. Most Indian black cotton soils are rich in the mineral montmorillonite, which is responsible for its swelling-shrinkage behaviour and is highly susceptible to moisture changes. To improve the engineering properties such as strength, volume stability and durability of such soils, so that construction of road pavement and foundations etc., can be done on these, soil stabilization has to be done. The soil properties can be improved using many methods such as mechanical stabilization, chemical stabilization, grouting, using geotextiles, using admixtures etc. The present investigation is done to evaluate the compaction parameters, Atterbergs Limits and unconfined compressive strength of black cotton soil stabilized by adding 5% to 30% of admixtures. The admixtures used for this study and cement and fly ash. The optimum http://www.iaeme.com/ijciet/index.asp 1236 editor@iaeme.com
Diana Alice Sugunan, G.Balamurali and S.Muthulakshmi percentage of cement and fly ash to be added can be evaluated from the results obtained. By adding this optimum percentage of cement and fly ash, to the black cotton soil, its undesirable characteristics can be modified using a suitable stabilization technique. 2. MATERIALS 2.1. Black cotton soil Black cotton soil is considered to be problematic soil as it show major volume changes due to change in its moisture content. This volume change cause wide spread damages to building and roads necessitating stabilization of such soil prior to the construction. On account of high swelling and shrinkage potential these soils has to be stabilised before construction of the structure. 2.2. Cement Ordinary Portland cement (OPC) is most important type of cement. The OPC was classified into three grades, namely 33 grade, 43 grade and 53 grade depending upon the strength of the cement. Why do u use cement in stabilisation? Properties of cement include fineness, setting time, soundness, specific gravity and compressive strength. The fineness of cement is a measure of the particle size of cement. 2.3. Fly ash Fly ash, the fine particulate waste material produced by pulverized coal-based thermal power station, is an environmental pollutant, it has a potential to be a resource material. It is one of the residues formed in combustion, and consists of the fine particles that rise with the flue gases. In an industrialized term, fly ash typically refers to ash formed during combustion of coal. Fly ash is captured from the chimneys of coal-fired power plants, and mutually with bottom ash, which is separate from the bottom of the furnace is in this case mutually identified as coal ash. The fly ash manufacture in India is around 100 million ton per year and ash ponds presently occupy nearly 64,000 acres of land. Since the disposal of such large quantities of fly ash poses environmental problem, the alternative methods for the use of the same has to be done. Therefore it finds major application in construction field and soil stabilisation techniques. 3. TESTING OF MATERIALS 3.1. Tests There are several tests conducted for analysis of Mix of Soil with cement and Soil with fly ash in proportions of 0% to 50% for stabilization of soil. The tests are: Determination of Maximum Dry Density Determination of Optimum Moisture Content Specific gravity test on mix Standard Proctor Compaction Test Determination of Consistency Limit Determination of Shrinkage limits CBR test on mix http://www.iaeme.com/ijciet/index.asp 1237 editor@iaeme.com
Study on Soil Stabilization Using Cement and Fly Ash 3.2. Effect of fly ash and cement on geotechnical properties of soil: 3.2.1. Determination of MDD and OMC of Mix Based on the laboratory tests conducted on black cotton soil mixed with fly ash from 0% to 50% by dry weight of the soil. The following results observed are, Maximum Dry Density reduced from 2.08 to 1.51. Optimum Moisture Content increased from 14% to 23%. Table 1 Properties of soil and cement mix Combination MDD (%) OMC(%) Black cotton soil 2.08 14 BCS + 10% Cement 1.69 15 BCS + 20% Cement 1.66 18 BCS + 30% Cement 1.636 19 BCS + 40% Cement 1.54 21 BCS + 50% Cement 1.44 24 Figure 1 MDD of Soil + Fly ash Figure 2 OMC of Soil + Fly ash 3.2.2. Standard Proctor Compaction Test Based on the laboratory tests conducted on black cotton soil mixed with cement from 0% to 50% by dry weight of the soil. The following results observed are, Maximum Dry Density reduced from 2.08 to 1.44. Optimum Moisture Content increased from 14% to 24%. http://www.iaeme.com/ijciet/index.asp 1238 editor@iaeme.com
Diana Alice Sugunan, G.Balamurali and S.Muthulakshmi Figure 3 Proctor compaction results for Cement Figure 4 Proctor compaction results for Fly ash Compaction test data shows that with increasing in the percentage of fly ash and cement OMC values are increasing and MDD values are decreasing. This increase in OMC values are due to the development of flocculated structure which resists the compaction effort and the particles in the soil-fly ash matrix requires more water to mobilize and less solids occupied in the given volume and low dry densities are also due to nature and low specific gravity of fly ash particles. 3.2.3. Consistency Limits Test Based on the laboratory tests conducted on black cotton soil mixed with cement from 0% to 50% by dry weight of the soil. The following results observed are, Liquid limit of samples are decreasing with increasing of fly-ash mix with black cotton soil. It has been found that the liquid limit decreased from the (54% to 35%). Plastic limit of the soil and fly ash mix decreasing from 26.9% to 16.6%. Plasticity Index decreased from 27.1% to 18.4%. http://www.iaeme.com/ijciet/index.asp 1239 editor@iaeme.com
Study on Soil Stabilization Using Cement and Fly Ash Figure 5 Consistency Limits for soil + Fly Ash Figure 6 Consistency Limits for soil + Fly Ash From the consistency test data, it is identified that as the percentage of fly ash is increasing liquid limit and plasticity index values are decreasing and plastic limit values are decreasing. The decrease in liquid limit is due to the decrease in diffused double layer by replacement of clay particles by fly ash particles and increase in plastic limit is due to the development of shear resistance at inter particle level and the particles in soil-fly ash matrix require more water to mobilize for rolling. 3.2.4. California Bearing Ratio Test From the above results, it was observed that the values of CBR were increasing from 0% to 20% (1.8-18.8) of cement mixed with soil. And then the values are decreasing from 20% to 50 % (18.8-6.5) of cement and soil mix. http://www.iaeme.com/ijciet/index.asp 1240 editor@iaeme.com
Diana Alice Sugunan, G.Balamurali and S.Muthulakshmi Figure 7 CBR Results Based on the laboratory tests conducted on black cotton soil mixed with cement and fly ash from 0% to 50% by dry weight of the soil. The following results observed are, For Fly ash, the maximum CBR value obtained at 30 % of fly ash (10.8). For Cement, the maximum CBR value obtained at 20 % of fly ash (18.8). 3.2.5. Determination of Shrinkage limits On the testing of mix of soil with cement and fly ash, we obtain the following results are: Table 2 Test results for Soil with Fly ash (%) S.No Fly ash (%) Water content (%) Shrinkage limit (%) Shrinkage ratio 1 0 46.6 21.4 1.35 2 10 44.8 18.8 1.33 3 20 42.85 16.33 1.31 4 30 40.74 13.09 1.29 5 40 38.8 10.97 1.32 6 50 37.04 8.57 1.36 Table 3 Test results for Soil with Cement (%) S.No Cement (%) Water content (%) Shrinkage limit (%) Shrinkage ratio 1 0 46.6 21.4 1.35 2 10 46.5 21.1 1.33 3 20 46.4 19.7 1.31 4 30 46.15 19.42 1.27 5 40 45.8 18.72 1.20 6 50 43.4 11.02 1.10 3.2.6 Specific Gravity Test The specific gravity test is conducted for the mix of soil with cement and flyash and results obtained are given below figures. http://www.iaeme.com/ijciet/index.asp 1241 editor@iaeme.com
Study on Soil Stabilization Using Cement and Fly Ash S.No Proportion (%) Table 4 Specific gravity of Soil and Fly ash mix Specific gravity for cement mix Specific gravity for fly ash mix 1 0 2.44 2.44 2 10 2.32 2.13 3 20 2.29 2.04 4 30 2.16 1.98 5 40 2.08 1.92 6 50 2.01 1.89 4. RESULTS AND DISCUSSIONS Based on the laboratory tests conducted on black cotton soil mixed with fly ash from 0% to 50% by dry weight of the soil. From the proctor compaction test the following results observed are, Maximum Dry Density reduced from 2.08 to 1.51. Optimum Moisture Content increased from 14% to 23%. From the consistency limits data, Liquid limit of samples are decreased from the 54% to 35%. Plastic limit of the samples decreased from 26.9% to 15.9%. Plasticity Index decreased from 27.1% to 19.1%. The values of CBR were increasing from 0% to 30% and then decreased from 30% to 50%. Maximum CBR value obtained from the test is 10.8. Shrinkage limit of the sample decreased from 21.4 to 8.57. Specific gravity of the sample decreased from 2.44 to 2.01 Based on the laboratory tests conducted on black cotton soil mixed with cement from 0% to 50% by dry weight of the soil. From the proctor compaction test the following results observed are, Maximum Dry Density reduced from 2.08 to 1.44. Optimum Moisture Content increased from 14% to 24%. From the consistency limits data, Liquid limit of samples are decreased from the 54% to 36%. Plastic limit of the samples decreased from 26.9% to 16.6%. Plasticity Index decreased from 27.1% to 18.4%. The values of CBR were increasing from 0% to 20% and then decreased from 20% to 50%. Maximum CBR value obtained from the test is 18.8. Shrinkage limit of the sample decreased from 23.8 to 11.02. Specific gravity of the sample decreased from 2.44 to 1.89. http://www.iaeme.com/ijciet/index.asp 1242 editor@iaeme.com
Diana Alice Sugunan, G.Balamurali and S.Muthulakshmi ACKNOWLEDGMENT The authors would like to express their sincere thanks to friends and family for providing the necessary support required for the present study. REFERENCES [1] Brooks M. Robert (2009) Soil Stabilization with fly ash and rice husk ash International Journal of Research and Reviews in Applied Science, Volume 1, Issue 3, pp. 209-217. [2] Phanikumar B.R.,Radhey S.Sharma(2004) Effect of fly ash on Engg. Properties of Expansive soil Journal of Geotechnical and Geoenvironmental Engineering vol.130, no 7, July, pp.764-767. [3] Satyanarayana P.V.V, Kumar S.Hemanth, Praveen P, and Kumar B.V.Suresh(2013): A study on strength characteristics of expansive soil-fly-ash mixes at various moulding water content International Journal of Recent Technology and Engineering (IJRTE) ISSN: 2277-3878, Volume-2, Issue-5, pp. 145-149. [4] Zachary G. Thomas (2002), Engineering properties of soil-fly ash subgrade mixture, Graduate Research Report, Lowa State University, Ames, Lowa. [5] Krishna Rao.C.V, Satyanarayana.P.V.V, Rama Rao.R (2002) Fly ash - a Construction Material in Rural Roads Conference 4th International Conference on Ground Improvement Techniques Volume 2 Issue 1 pp. 645-648 [6] Pandian, N.S. and Krishna, K.C. (2002), California Bearing Ratio Behavior of Cement Stabilized Fly Ash-Soil Mixes, Journal of Testing and Evaluation, 30(6), 1-5. [7] Satyanarayana.P.V.V, Krishna rao.c.v, Rama Rao.R (2004) Utilization of Lime fly Ash Stabilized Expansive Soil in Roads and Embankments Indian Geotechnical Conference Volume 1 Issue 1 pp. 465-467. [8] Hairulla and Philipus Betaubun, Engineering of Clay Soil Stabilization with Cement and Fiber on CBR Value for Road Materials in Merauke District. International Journal of Civil Engineering and Technology, 9(8), 2018, pp. 562-567. [9] Zaid Hameed Majeed, Ibtehaj Taha Jawad and Haider M. Owaid, Fine Grained Soil Stabilization Using Binary Blending of Calcium Carbide Residue and Palm Oil Fuel Ash, International Journal of Civil Engineering and Technology, 9(4), 2018, pp. 939 950. [10] C. Giriprasad and Dr. Ajayswarup, Geotechnology of using Geogrid GGEN and GGUEN Nails in Soil Stabilization of BC Soil with Comparative Study, International Journal of Civil Engineering and Technology, 9(4), 2018, pp. 320 326. http://www.iaeme.com/ijciet/index.asp 1243 editor@iaeme.com