STUDY ON STABILIZATION OF BLACK COTTON SOILS USING CEMENT FLYASH AND GGBS

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 4, April 2017, pp Article ID: IJCIET_08_04_225 Available online at aeme.com/ijciet/issues.asp?jtype=ijciet&vtyp pe=8&itype=4 ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed STUDY ON STABILIZATION OF BLACK COTTON SOILS USING CEMENT FLYASH AND GGBS B. Rajendra and K. Siva Gopi B.Tech, Student, Department of Civil Engineering, K L University, Andhra Pradesh, India. Dr. Ch. Hanumantha Rao Professor, Department of Civil Engineering, K L University, Andhra Pradesh, India. ABSTRACT The correct stabilization of foundation soils constitutes an increasingly important issue in the present Civil Engineering world. Soil stabilization with Cement, Fly-Ash and GGBS is a way of achieving the proposed goals, which is at the same time inexpensive and easy to apply in practically any type of soil. Black Cotton soils which shows major volume changes due to change in moisture content. These soils gets expand when water or moisture content is added and shrink when dry. By adding the other materials to the soil we can improve the stability and engineering properties of soil. The main goal in this project work is to quantify the benefits achieved with the Cement, Fly-Ash and GGBS stabilization of a Black Cotton soil. Utilization of industrial waste materials like Fly-Ash, GGBS will increase the soil strength and less in cost. The performancee of Cement, Fly-Ash and GGBS modifiedd soils will be evaluated using Standardd Proctor test and Modified Proctor test. Based on the performance tests, after doing a comparative study the optimum amount of material to be used for the black cotton soil which will give more stability will be known. Key words: Black Cotton Soils, Cement, Fly-Ash, Ground Granulated Blast Furnace Slag (GGBS), Soil Stabilization, Standard Proctor Test and Modified Proctor Test. Cite this Article: B. Rajendra, K. Siva Gopi and Dr. Ch. Hanumanthaa Rao Study on Stabilization of Black Cotton Soils Using Cement Flyash And GGBS, International Journal of Civil Engineering and Technology, 8(4), 2017, pp Type=4 1. INTRODUCTION For any civil engineering structure the foundation is very important and it should to be strong to support the structure. Soil stabilization will improve the engineering properties of soil such as strength and durability. Soil stabilization is a process of blending of mixing materials with editor@iaeme.com

2 B. Rajendra, K. Siva Gopi and Dr. Ch. Hanumantha Rao the soil. In this project we are studying on the soil stability properties of Black Cotton Soils using the materials like Cement, Fly-Ash and GGBS. In order to make the foundation to be strong the soil around it plays a very critical role. Expansive soils are a worldwide problem in constructions. So these are need for these soils to be stabilized. Large scale constructions on Black cotton soils can be done by adding other materials (Cement, Fly Ash and GGBS) to it without effecting the cost. To provide and detailed information on the changes in engineering properties of black cotton soils by adding different materials in varied percentages and compare with each other. By these tests the water content in soil is decreased, and the maximum dry density can be increased. The characteristics of Black Cotton soils, with different proportions (10%, 20%, and 30%) of Cement, Fly-Ash and GGBS one at a time are discussed and the evolution of their properties of Black Cotton soil are studied. 2. OBJECTIVE To compare at maximum stabilization properties of black cotton soils with the addition of flyash, cement and GGBS. 3. MATERIAL USED In our project the used binders are: 3.1. Cement 3.2. Fly ash 3.3. Ground Granulated Blast Furnace Slag 3.1. Cement Cement is the oldest binding agent since the invention of soil stabilization technology in 1960 s. It may be considered as primary stabilizing agent or hydraulic binder because it can be used alone to bring out the stabilizing action required. Cement reaction is not dependent on soil minerals, and key role is its reaction with water that may be available in any soil. This can be the reason why cement is used for stabilize a wide range of soils Fly ash Fly ash is a by-product of coal fired electric power generation facilities: it has little cementitious properties compared to lime and cement. Most of the fly ashes belong to secondary binders: these binders cannot produce the desired effect on their own. However, in the presence of a small amount of activator, it can react chemically to form cementitious compound and leads to improved strength of soft soil. Fly ashes are readily available, cheaper and environmental friendly. There are two main classes of fly ashes: class C and class F Ground Granulated Blast Furnace Slag These are the by-product in pig iron product. The chemical compositions are similar to that of cement. It is however, not cementitous compound by itself, but it possesses latent hydraulic properties which upon addition of lime or alkaline material the hydraulic properties can develop. Depending on cooling system, Sherwood itemized slag in three forms, namely air cooled slag hot slag after leaving the blast furnace may be slowly cooled in open air, resulting into crystalized slag which can be crushed and used as aggregate. Granulated slag containing of hot slag may result into formation of vitrified slag. The granulated blast furnace slag is a result of water during quenching process, while, the use of air in the process of quenching may result into information of Granulated slag. Expanded slag is formed under certain conditions; stream produced during cooling of hot slag will give rise to expanded slag editor@iaeme.com

3 4. METHODOLOGY Study on Stabilization of Black Cotton Soils Using Cement Flyash And GGBS 1. Preparation of soil samples by adding of varied percentages (10%, 20% and 30%) of Fly-ash, GGBS and Cement individually mixed with Black Cotton Soil. 2. Tests are conducted on these samples to know there engineering properties. 3. The obtained test results are compared with each other the see at what proportions and with what material the black cotton soil is more stable and less stable. Our project is mainly on comparing the Optimum Moisture Content and Maximum Dry Density of varied percentages (10%, 20% and 30%) of Fly-ash, GGBS and Cement individually mixed with Black Cotton Soil using Standard Proctor Test and Modified Proctor Test Preparation of sample A representative portion of air-dried soil material, large enough to provide about 5kg of material passing through a 19mm IS Sieve (for soils not susceptible to crushing during compaction) or about 15kg of material passing through a 19mm IS Sieve (for soils susceptible to crushing during compaction), should be taken. This portion should be sieved through a 19mm IS Sieve. Aggregations of particles completely broken down so that if the sample was sieved through a 4.75mm IS Sieve only List of Experiments Conducted 1. Particle size Analysis: This Particle size Analysis test is performed to determine the percentage of different grain sizes present within a soil sample. This sieve analysis is performed to obtain the distribution of the coarse, large-size particles. 2. Atterberg limits: The water content at which the soil changing from one state to another state are known as consistency limit or Atterberg limit. The Atteberg limits which are useful for engineering purposes are Liquid limit, Plastic limit and Shrinkage limit. These limits are expressed in percentages. i) Liquid limit: The liquid limit is expressed as the moisture content at which soil begins to behave as a liquid material and begins to flow. As the moisture content at which two sides of the groove formed in the soil sample come together and touch at a distance of 2 inch after 25 blows. ii) Plastic limit: The plastic limit is obtained by rolling a thread of the fine grain soil on a flat surface. If the soil is at a certain moisture it behave as plastic, this thread will decrease to a very narrow diameter. The sample can be remould again and the test repeated. As the moisture content falls due to evaporation and the thread will start to break at larger diameters. The plastic limit is defined as the moisture content where the thread breaks at diameter of 3.2 mm. A soil is considered non-plastic if a thread cannot be rolled out down to 3.2 mm at any moisture content. iii) Plasticity index: The plasticity index is measured as plasticity of a soil as size of a range of water content where the soil exhibits plastic properties. The Plasticity index is the difference between the liquid limit and the plastic limit. 1) Specific gravity test using density bottle method: The specific gravity of a material is defined as the ratio of the mass of a unit volume of a material to the mass density of gas-free distilled water at a stated temperature editor@iaeme.com

4 B. Rajendra, K. Siva Gopi and Dr. Ch. Hanumantha Rao 2) Proctor Compaction Test: This test is to determine the soil compaction properties, optimal water content at which soil can reach its maximum dry density. There are two types of proctor compaction tests. i) Standard Proctor Test / Light Compaction Test: Take 5 Kg oven dry sample, add water of 4-6% and mix it. Weigh empty mould without base plate and collar. Compact the soil in 3 layers of 25 blows at each layer with 2.5 kg rammer of 5 cm diameter free falling from a height of 30 cm. Weigh the mould without base plate and collar by trimming straight at edges of mould. Take small sample from mould for water content. Repeat the process by adding 2% of water to the sample every time until there is either decrease or no change in wet unit weight of compacted soil sample is observed. ii) Modified Proctor Test / Heavy Compaction Test: Take 5 Kg oven dry sample, add water of 4-6% and mix it. Weigh empty mould without base plate and collar. Compact the soil in 5 layers of 25 blows at each layer with 5 kg rammer free falling from a height of 45 cm. Weigh the mould without base plate and collar by trimming straight at edges of mould. Take small sample from mould for water content. Repeat the process by adding 2% of water to the sample every time until there is either decrease or no change in wet unit weight of compacted soil sample is observed. 5. RESULTS AND DISCUSSIONS 5.1. Grain size analysis test results S No Sieve Size (mm) Table 1 Grain size analysis of black cotton soil Soil Retained (grams) % Retained Cumulative % Retained % Finer % 4.8% 95.2% % 6.6% 93.4% % 11.6% 88.4% 4 600µ % 19.9% 80.1% 5 300µ % 39.6% 61.4% 6 150µ % 56.2% 43.8% 7 75µ % 59.5% 40.5% 8 PAN % 100% 0% 5.2. Atterberg limits of Back cotton soil i) Liquid Limit of Back cotton soil: Table 2 Liquid limit of black cotton soil. Pan % of water added No. of blows editor@iaeme.com

5 Study on Stabilization of Black Cotton Soils Using Cement Flyash And GGBS Liquid limit of black cotton soil is 60. ii) Plastic limit of Black cotton soil: Plastic limit of black cotton soil sample is 19. iii) Plasticity index of BC soil: (PI=LL-PL) Table 3 Plasticity index of black cotton soil Property Liquid limit 60 Plastic limit 19 Plasticity index 41 Plasticity index of our soil sample is 41. 1) Specific gravity test using density bottle method: Mass of empty bottle = m1 Mass of bottle + dry soil = m2 Mass of bottle + soil + water = m3 Mass of bottle + water = m4 Specific gravity, G = (m2-m1)/((m2-m1)-(m3-m4)) Average Specific gravity of Black Cotton Soil is Soil 2) Standard Proctor Test: Standard Proctor Test Optimum Moisture content Maximum Dry Density Black Cotton Soil 18.73% 1.62 g/cc B.C Soil + 10% GGBS 14.80% 1.65 g/cc B.C Soil + 20% GGBS 15.90% 1.72 g/cc B.C Soil + 30% GGBS 16.20% 1.78 g/cc B.C Soil + 10% FA 16.70% 1.63 g/cc B.C Soil + 20% FA 16.90% 1.68 g/cc B.C Soil + 30% FA 17.60% 1.86 g/cc B.C Soil + 10% Cement 16.10% 1.78 g/cc B.C Soil + 20% Cement 16.70% 1.81 g/cc B.C Soil + 30% Cement 17.50% 1.86 g/cc editor@iaeme.com

6 B. Rajendra, K. Siva Gopi and Dr. Ch. Hanumantha Rao Standard Proctor Test Water Conten t 14.2 BCS BCS+30%Cement BCS+20%Cement BCS+10%Cement BCS+30%FlyAsh BCS+20%FlyAsh BCS+10%FlyAsh BCS+30%GGBS BCS+20%GGBS BCS+10%GGBS ) Modified Proctor Test: Dry Density Figure 1 Standard Proctor Test Modified Proctor Test Optimum Moisture content Maximum Dry Density Black Cotton Soil 18.97% 1.63g/cc B.C Soil + 10% GGBS 14.90% 1.67 g/cc B.C Soil + 20% GGBS 15.90% 1.76 g/cc B.C Soil + 30% GGBS 15.90% 1.80 g/cc B.C Soil + 10% FA 16.70% 1.65 g/cc B.C Soil + 20% FA 17.40% 1.70 g/cc B.C Soil + 30% FA 17.70% 1.87 g/cc B.C Soil + 10% Cement 16.60% 1.79 g/cc B.C Soil + 20% Cement 16.80% 1.85 g/cc B.C Soil + 30% Cement 18.10% 1.88 g/cc Modified Proctor Test Water Content BCS+30%Cement BCS+20%Cement BCS+10%Cement BCS+30%FlyAsh BCS+20%FlyAsh BCS+10%FlyAsh BCS+30%GGBS BCS+20%GGBS BCS+10%GGBS BCS Dry Density Figure 2 Modified Proctor Test editor@iaeme.com

7 Study on Stabilization of Black Cotton Soils Using Cement Flyash And GGBS The Above Tables and Graphs shows the Optimum Moisture Content and Maximum Dry Density of varied percentages of Fly-ash, GGBS and Cement individually mixed with Black Cotton Soil using Standard Proctor Test and Modified Proctor Test. It s been observed that at 14.8% water content and 1.8% dry density the sample with 30% cement and 30% Fly-ash giving the maximum stabilization properties in standard proctor test. Also in modified proctor test same changes are observed at 18.97% of water content and 1.8% dry density. 6. CONCLUSIONS From the study the GGBS gives less dry density than Cement and Fly Ash at any varied percentage but increases compared to normal black cotton soil. Cement gives the maximum dry density than the other materials but it is not recommended. Fly-ash and Cement gives the dry density values nearly equal to each other. Cement is not recommended because it is not economical and causes pollution. Fly-ash is giving more stability to soil compared to GGBS and cement. Fly-ash is recommended for soil stabilization because it is economical and environmental friendly. REFERENCES [1] Analysis of Engineering Properties of Black Cotton Soil & Stabilization Using By Lime. (IJERA, ISSN , Volume 4, Issue 5, Version 3, May 2014, pp.25-32) By Kavish S. Mehta, Rutvij J. Sonecha, Parth D. Daxini, Parth B. Ratanpara, Miss Kapilani S. Gaikwad. [2] Augmenting the Properties of Black Cotton Soil Using Additives (IJNTR, ISSN , Volume 1, Issue 3, July 2015, Pages 42-45) By Manjularani.P, Channabasavaraj.W, MdKhajaMoniuddin. [3] Behavior of Clayey Soil Stabilized with Rice Husk Ash & Lime (IJETT, ISSN , Volume 11, Number 1, May 2014) By B.Suneel Kumar & T.V.Preethi. [4] Comparative Study of Black Cotton Soil Stabilization with RBI Grade 81 and Sodium Silicate (IJIRSET, ISSN , Volume 2, Issue 2, Feb 2013) By K.V. Madurwar, P.P. Dahale, A.N.Burile. [5] Effect on Strength Characteristics of Expansive Soil Using Sisal Fibre and Waste Materials (IJSR, ISSN , Volume 5, Issue 9, Sep 2016) By Amrutha Mathew, Dr. Raneesh. K.Y. [6] Efficacy of Industrial waste admixture in Improving Engineering Performance of Clayey soil - A quantitative study (AJER, e-issn , p-issn , Volume 3, Issue 9, pp , 2014) By U. Arun Kumar. [7] Stabilization of Expansive Soils using Low Cost Materials (IJEIT, ISSN Volume 2, Issue 11, May 2013) By Monica Malhotra, Sanjeev Naval. [8] Soil stabilization using industrial waste and lime (IJSRET, ISSN , Volume 4, Issue 7, July 2015) By M. Adams Joe, Oman and A. Maria Rajesh. [9] Stabilization of soft soil with granulated blast furnace slag and fly ash (IJRET, ISSN , Volume 2, Issue 2, Feb 2013) By Laxmikant Yadu and R.K. Tripathi. [10] Studies On Geotechnical Properties Of Black Cotton Soil Stabilized With Furnace Dust And Dolomitic Lime (IRJET, e-issn , p-issn , Volume 2, Issue 8, Nov 2015) By Haresh D. Golakiya, Chandresh D. Savani editor@iaeme.com