IMPROVEMENT OF SHEAR STRENGTH OF SOIL USING BITUMEN EMULSION

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 7, Issue 6, November-December 216, pp , Article ID: IJCIET_7_6_17 Available online at ISSN Print: and ISSN Online: IAEME Publication IMPROVEMENT OF SHEAR STRENGTH OF USING BITUMEN EMULSION R. Deby Linsha, Y. Preethy Dharanya, V. Vinodhini and C. Pavithra Assistant Professor, Vel Tech, Avadi, Chennai, Tamil Nadu, India ABSTRACT Soil is one of the nature s most abundant construction materials. Almost all type of construction is built with or upon the soil. If the sub grade is not enough good the whole structure will face failure such as cracks. Therefore the sub grade is normally replaced with stronger soil material so as to improve the strength but this is not economical. In this project the strength of soil is increased by adding bituminous emulsion instead of replacing with stronger soil. The initial strength of the soil is determined by conducting soil tests such as sieve analysis, plastic limit, liquid limit, shrinkage limit, Modified proctor compaction test and California bearing ratio tests. The results obtained are then compared with the soil treated with 1%, 2% and 25% of bitumen emulsion. Key words: bitumen, bituminous emulsion, shear strength, soil stabilisation. Cite this Article: R. Deby Linsha, Y. Preethy Dharanya, V. Vinodhini and C. Pavithra, Improvement of Shear Strength of Soil Using Bitumen Emulsion. International Journal of Civil Engineering and Technology, 7(6), 216, pp INTRODUCTION The foundation is very important and has to be strong enough to support the entire structure. In order for the foundation to be strong, the soil around it plays a very critical role. So we need to have proper knowledge about their properties and factors which affect their behaviour to work with soil. The process of soil stabilisation helps to achieve the required properties in a soil needed for the type of construction work. In this thesis, the strength of the soil is improved by using bituminous emulsion. Bitumen emulsion is a mixture of water & bitumen. As bitumen is an oil product it cannot be mixed with water. Hence an emulsifier (a surface active agent) is added with water before bitumen. Addition of emulsifier with water before adding bitumen into minute particles and keeps it dispersed in suspension. The term emulsion means that dispersion of small droplets of one liquid in another liquid. Types of emulsion are oil in-water (continuous phase is water and the disperse phase is an oily) and water-in-oil (continuous phase is an oil and the disperse phase is water). Here the emulsifier is used as kerosene with water. Initially the properties of soil are determined by using conducting sieve analysis, plastic limit, liquid limit, specific gravity and shrinkage limit. The strength of soil is determined by modified proctor compaction test and California bearing ratio tests and the results are compared with the soil after treated with bituminous emulsion editor@iaeme.com

2 R. Deby Linsha, Y. Preethy Dharanya, V. Vinodhini and C. Pavithra 1.1. Objective Verdict the variation of strength in the soils by using the bitumen emulsion performance (different proportions) applied and determining the variation in properties of soil. 2. METHODOLOGY Methodology involves collection of soil sample (laterite soil) from the site (Avadi lake), study of soil properties by conducting tests (particle sieve analysis, Atterberg s limits, direct shear tests, relative density, unconfined compression test, California bearing ratio, modified proctor compaction, specific gravity), addition of bitumen Emulsion to the soil at different proportions, testing of bitumen emulsion added soil and comparison of test results. The methodology of this study is given in the following flow chart. Figure 1 Methodology Chart 3. MATERIALS AND PROCEDURE The materials used in this project are collected soil sample (laterite soil), bitumen and kerosene Physical Properties of Bitumen Adhesion: Bitumen has the ability to adhere to a solid surface in a fluid state depending on the nature of the surface. The presence of water on the surface will prevent adhesion. Resistance to Water: Bitumen is water resistant. Under some conditions water may be absorbed by minute quantities of inorganic salts in the bitumen or filler in it. Hardness: To measure the hardness of bitumen, the penetration test is conducted, which measures the depth of penetration in tenths of mm. of a weighted needle in bitumen after a given time, at a known temperature. Commonly a weight of 1gm is applied for 5 sec at a temperature of 77 F. The penetration is a measure of hardness. Typical results are 1 for hard coating asphalt, 15 to 4 for roofing asphalt and up to 1 or more for water proofing bitumen editor@iaeme.com

3 Improvement of Shear Strength of Soil Using Bitumen Emulsion Viscosity and Flow: The viscous or flow properties of bitumen are of importance both at high temperature during processing and application and at low temperature to which bitumen is subjected during service. The flow properties of bitumen s vary considerably with temperature and stress conditions. Deterioration, or loss of the desirable properties of bitumen, takes the form of hardening. Resultantly, decrease in adhesive and flow properties and an increase in the softening point temperature and coefficient of thermal expansion. Softening point: Softening point is the temperature at which a steel ball falls a known distance through the bitumen when the test assembly is heated at a known rate. Usually the test consist of a (3/8)in dia steel ball, weight 3.5 gm, which is allowed to sink through a (5/8) in dia, (1/4) in thick disk of bitumen in a brass ring. The whole assembly is heated at a rate of 9 F per min. Typical values would be 24 F for coating grade asphalts, 14 F to 22 F for roofing asphalt and down to 115 F for bituminous water proofing material. Ductility: Ductility test is conducted to determine the amount bitumen will stretch at temperature below its softening point. A briquette having a cross sectional area of 1 in2 is placed in a tester at 77 F. Ductility values ranges from to over 15 depending on the type of bitumen Chemical Properties of Bitumen Molecular weight wise, bitumen is a mixture of about 3-2 chemical components, with an average of around 5-7. Elementally, it is around 95% carbon and hydrogen (± 87% carbon and ± 8% hydrogen), and up to 5% sulphur, 1% nitrogen, 1% oxygen and 2ppm metals Dry Sieve Analysis A gradation test is a practice used to assess the particle size distribution of a granular material. The standard grain size analysis test determines the relative proportions of different grain sizes as they are distributed among certain size ranges. With the details obtained from grain size distribution curves, to determine the suitability of soil for different field of construction. Here it is concluded that the soil sample collected is well graded soil. S.No IS sieve size in mm Table 1 Dry Sieve Analysis Retain % weight Cum weight Pass % pan Mix Proportion The soil sample is made into a mixture bitumen emulsified soil by adding bitumen and bitumen emulsifier. In this study kerosene is used as a bitumen emulsifier. The various proportions are prepared with 1%, 2% and 25 % of bitumen emulsion mixed to the soil sample editor@iaeme.com

4 R. Deby Linsha, Y. Preethy Dharanya, V. Vinodhini and C. Pavithra 4. RESULTS AND DISCUSSION The characteristic study on the collected soil sample was conducted previously and then the respective tests are conducted for the bitumen emulsion mixed soil sample of three different proportions. The test results are compared and given below Specific Gravity Test Specific gravity is defined as the ration of the weight of a given volume of soil solids at a given temperature to the weight of an equal volume of distilled water at that temperature, both weights being taken in air. The Indian standards specify 27 o C as the standard temperature for reporting the specific gravity. This test is to determine the specific gravity of soil grains. Table 2 Specific gravity test S.No Sample Specific gravity 1 Normal soil sample Soil with 1% bitumen emulsion Soil with 2% bitumen emulsion Soil with 25% bitumen emulsion Specific Gravity Specific Gravity Test Normal soil 1% 2% 25% Bitumen Range insoil Sample Figure 1 Graph of Specific gravity Test 4.2. Liquid Limit Liquid limit is defined as the minimum water content at which the soil is still in the liquid state but has a small shearing strength against flowing which can be measured by standard available means or weight of the soil, at the boundary between the liquid and plastic states of consistency. The moisture content at this boundary is arbitrarily defined as the water content at which two halves of a soil cake will flow together, for distance of 12.7 mm along the bottom of a groove of standard dimensions separating the two halves, when the cup of standard liquid limit apparatus is dropped 25 times from a height of 1 mm at the rate of two drops/second. The liquid limit test is conducted on the various soil samples and the results are tabulated below editor@iaeme.com

5 Improvement of Shear Strength of Soil Using Bitumen Emulsion Table 3 Liquid Limit Test S.No Sample Liquid limit (%) 1 Normal soil sample Soil with 1% bitumen emulsion Soil with 2% bitumen emulsion Soil with 25% bitumen emulsion LIQUID LIMIT TEST 2 Liquid Limit Normal soil 1% 2% 25% Bitumen Range insoil Sample Figure 2 Graph of Liquid Limit Test 4.3. Plastic Limit Plastic limit refers to the minimum water content at which soil will just begin to crumble when rolled into a thread approximately 3mm in diameter using a ground glass plate or other acceptable surface. It is the water content corresponding to an arbitrary limit between plastic and semisolid states of consistency of soils. The plastic limit test is conducted on the various soil samples and the results are tabulated below. Table 4 Plastic Limit S.No Sample Plastic limit (%) 1 Normal soil sample Soil with 1% bitumen emulsion Soil with 2% bitumen emulsion Soil with 25% bitumen emulsion editor@iaeme.com

6 R. Deby Linsha, Y. Preethy Dharanya, V. Vinodhini and C. Pavithra Plastic limit 3.% 25.% 2.% 15.% 1.% 5.%.% PLASTIC LIMIT 1% 2% 25% Bitumen Range in Soil Sample Figure 3 Graph of Plastic Limit 4.4. Standard Proctor Test From the Standard proctor test we are examining that the optimal moisture content at which a given soil type will become most dense and achieve its maximum dry density of the soil sample. Table 5 Standard Proctor Test S.No Sample Maximum dry density(g/cc) 1 Normal soil sample Soil with 1% bitumen emulsion Soil with 2% bitumen emulsion Soil with 25% bitumen emulsion SPT % 2% 25% MAXIMUM DRY DENSITY Figure 4 Graph of Standard Proctor Test editor@iaeme.com

7 Improvement of Shear Strength of Soil Using Bitumen Emulsion 4.5. Relative Density To determine the relative density of the soil samples with different proportions. Table 6 Relative Density S.No Sample Relative density (%) 1 Normal soil sample Soil with 1% bitumen emulsion Soil with 2% bitumen emulsion Soil with 25% bitumen emulsion RELATIVE DENSITY 1% 2% 25% RELATIVE DENSITY Figure 5 Graph of Relative Density 4.6. Unconfined Compression Test This test is to determine the shear parameters of the soil. Table 7 Unconfined Compression Test S.No Sample Unconfined compression strength(n/ ) 1 Normal soil sample 43 2 Soil with 1% bitumen emulsion 75 3 Soil with 2% bitumen emulsion Soil with 25% bitumen emulsion editor@iaeme.com

8 R. Deby Linsha, Y. Preethy Dharanya, V. Vinodhini and C. Pavithra UNCONFINED COMPRESSION TEST 1% 2% 25% COMPRESSION STRENGTH 4.7. Direct Shear Test To determine the shear strength of the soil sample. Figure 6 Graph of Unconfined Compression Test Table 8 Direct Shear Test S.No Sample Shear strength(kg/ ) 1 Normal soil sample Soil with 1% bitumen emulsion.85 3 Soil with 2% bitumen emulsion.5 4 Soil with 25% bitumen emulsion DIRECT SHEAR TEST 1% 2% 25% SHEAR STRENGTH Figure 7 Graph of Direct Shear Test editor@iaeme.com

9 Improvement of Shear Strength of Soil Using Bitumen Emulsion 4.8. California Bearing Ratio Test To determine the California Bearing Ratio by conducting load penetration test. Table 9 California Bearing Ratio Test S.No Sample 2.5 mm 5mm 1 Normal soil sample Soil with 1% bitumen emulsion Soil with 2% bitumen emulsion Soil with 25% bitumen emulsion CBR 1% 2% 25% 2.5 mm 5 mm Figure 8 California Bearing Ratio Test 5. CONCLUSION This study made a comprehensive examination of the effectiveness of soils on the performance of bitumen emulsion. The characteristics of soil sample were known from the tests conducted and the similar tests are conducted for the soil sample mixed with three different proportions of bitumen emulsion (1%, 2% and 25%). Test result indicate that with the increase of bitumen emulsion in the soil sample till 1% proportion ratio the soil strength is increased and after certain percentages ( 2% and 3%) its getting decrease. The results are shown that the strength of the soil is good when 1 % bitumen emulsion is added. REFERENCE [1] Justyna Mrugala (24)-Soil Stabilisation with Foamed Bitumen. [2] E.Kowalski and Dale W.Starry, Jr.Wirtgen America,Inc.,(27)Modern Soil Stabilization Techniques editor@iaeme.com

10 R. Deby Linsha, Y. Preethy Dharanya, V. Vinodhini and C. Pavithra [3] Maheswari G. Bismal and Ravikumar Badiger (July 215)Study On Stabilization Of Soil Using Sea Shell And Bitumen Emulsion. [4] K. Prashanth Kumar (October 214) Stabilization of Soil Using Bituminous Emulsions. [5] Tridib Goswami (May 214) A Laboratory Study on Use Of Bitumen Emulsion In Gravel Road. [6] SK. Wasim Anwar, Experimental Investigations on Mar shall and Modified Marshall Specimens by using Neat Bitumen. International Journal of Civil Engineering and Technology (IJCIET), 7(5), 216, pp [7] Talaat Abde-Wahed and Hassan Al Nageim, Investigating the Effects of Cement and Cement Kiln Dust as a Filler on the Mechanical Properties of Cold Bituminous Emulsion Mixtures. International Journal of Civil Engineering and Technology (IJCIET), 7 (1), 216, pp editor@iaeme.com