INFLUENCE OF MINERAL ADMIXTURE ON ELASTIC BEHAVIOUR OF RED SOIL CEMENT CONCRETE UNDER FLEXURAL LOADING

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 4, April 2018, pp , Article ID: IJCIET_09_04_021 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed INFLUENCE OF MINERAL ADMIXTURE ON ELASTIC BEHAVIOUR OF RED SOIL CEMENT CONCRETE UNDER FLEXURAL LOADING James Alexander. S and Prof. Antony Godwin Department of civil engineering, Karunya University, Coimbatore, Tamilnadu, India Dr. S. Alexander Superintending Engineer (Retired), Tamilnadu P.W.D, Former Principal, Dean & Professor of Engineering Colleges & Consulting Engineer (Civil), Tirunelveli , Tamilnadu, India ABSTRACT This study has been carried out for determining the elastic behaviour of red soil with mineral admixture in concrete.red soils major advantage is its availability and highly effective for usage in concrete as a partial replacement of fine aggregate and fly ash (mineral admixture) is highly effective for usage in concrete as a partial replacement of cement and cement consumption is less when red soil is mixed, consumption of cement is less depending upon the variety of mix proportions. In this study of elastic behaviour of red soil with mineral admixture in concrete, M20 and M25 mix proportions are tried for studying stress-strain, modulus of elasticity and toughness of red soil with mineral admixture in concrete. Microstructural investigation are done for plain concrete and red soil cement concrete samples to study the behaviour of it. Key words: Red Soil, Fly Ash, Partial Replacement, Microstructural Investigation. Cite this Article: James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander, Influence of Mineral Admixture On Elastic Behaviour of Red Soil Cement Concrete Under Flexural Loading, International Journal of Civil Engineering and Technology, 9(4), 2018, pp INTRODUCTION The utilization of soil in concrete is new in the study of civil engineering and soil happens to be of great importance to civil engineers in every ways of construction. Many researchers have shown their interest on red soil but none of the studies were in concrete with fine aggregate replacement and also none of the studies were in cement replacement with fly ash and their investigations in red soil & fly ash are, Strength characteristics of red soils blended with fly ash and lime was investigated & stress-strain was studied from it 6, Utilization of hypo sludge for editor@iaeme.com

2 James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander the stabilization of red soils along with cement and molasses was investigated & unconfined compressive strength was studied from it 7, Effect of chemical admixtures on the engineering properties of red earth treated with cement was investigated & atterberg limit was studied from it 8, Experimental study on strength behaviour of cement blended soil-fly ash mixtures was investigated & optimum replacement of fly ash and unconfined compressive strength was studied from it 9. An Experimental Investigation of Red Soil Based Geopolymer Mortar Without Portland cement was investigated & micro structure was studied from it 1. This present study is purely based on the concrete with red soil and fly ash added to it. The partial replacements of fine aggregate 2 with Red soil and addition of mineral admixture (Fly ash) shows significant rise in the strength as well as in terms of economic in concrete 3. There is a need in the technical data for red soil 2 with mineral admixture in concrete to observe the elastic behaviour in this literature. This subject is a continuation of the previous study of red soil cement concrete. The state of this subject has proceeded in the addition of mineral admixture with red soil 6 cement concrete. The work done is in the stage of confirming that mineral admixture gives positive results in addition to the red soil cement concrete 5. Red soils major advantage is its availability and highly effective for usage in concrete as a partial replacement 4 and cement consumption is less when red soil is mixed, consumption of cement is less depending upon the variety of mix proportions. In the Previous study 1:1.5:2.75 mix proportion is used and it enhanced the performance of the red soil cement concrete. M20 and M25 grade mix proportions are tried in this study of elastic behaviour of red soil with mineral admixture in concrete. Red soil availability is in all kind of areas and it has unlimited resources in all areas which can be effectively used for admixture of concrete in constructing buildings. Red soil is formed due to weathering of igneous and metamorphic rocks and fly ash is obtained from the coal burning process which can be replaced with cement & it makes it as cost effective. It is highly impervious after it is mixed with concrete because of its size and its colour is in red due to the presence of iron in it. In India regions, the availability of red soil is in Tamilnadu, Karnataka, Andhra Pradesh, Orissa, Jharkhand and it is also available throughout the world. In this study, red soil is taken from semmedu, Coimbatore, Tamilnadu. 2. IMPORTANCE OF RED SOIL Chemical properties of red soil Red soil is rich in iron oxide, but deficient in nitrogen and lime. Table 1 shows the chemical composition of red soil. Table 1 Chemical Composition of Red Soil Composition Percentage by weight (%) Non-soluble material Iron 3.61 Aluminium 2.92 Organic matter 1.01 Magnesium 0.70 Lime 0.56 Potash 0.24 Soda 0.12 Carbon dioxide 0.30 Phosphorus 0.09 Nitrogen editor@iaeme.com

3 Influence of Mineral Admixture On Elastic Behaviour of Red Soil Cement Concrete Under Flexural Loading Table 2 Chemical Composition of Fly ash Composition Percentage by weight (%) Sio Al2o Fe2o Cao Mgo Tio K2o Na2o Loi Its colour is mainly due to ferric oxides occurring as thin coatings on the soil particles while the iron oxide occurs as hematite or as hydrous ferric oxide, the colour is red and when it occurs in the hydrate form as limonite the soil gets a yellow colour. Ordinarily the surface soils are red while the horizon below gets yellowish colour. Properties to be studied for red soil with mineral admixture in concrete - stressstrain, modulus of elasticity and toughness. The target of red soil with mineral admixture in concrete study is to obtain the stress strain, modulus of elasticity as per different codal provisions and toughness. Only the partial replacement of red soil is done and only 1/3 rd & 1/2 of sand is replaced by red soil and fly ash replacement with cement ranges from (5% - 30%). In this study only partial replacement of red soil is observed and full replacement of red soil is not done in this subject. Materials used The Cement used in this study is ordinary Portland cement of grade 53 is used in the study of red soil with mineral admixture 6 in concrete, Cement is replaced in this study for various percentages with fly ash 6. The Fine Aggregate used in this study is Sand which is used as one of the fine aggregate content in this study and the other fine aggregate content is red soil 9. Sand is sieved in 3.35mm sieve for using it in concrete mix for red soil with mineral admixture in concrete. According to the red soil with mineral admixture 7 in concrete mix proportion, the fine aggregate can be used as two by third of the total fine aggregate and also one by two of the total fine aggregate. The Coarse aggregate used in the study of red soil with mineral admixture in concrete is sieved through 20 and 12.5mm sieve sizes. Coarse aggregate passing through 20mm sieve and retaining through 12.5mm sieve is sieved and used for concrete mix. The Red soil content used in this study is a partial replacement of fine aggregate 9. Red soil is sieved through 500micron sieve size for using it in concrete mix. According to the mix proportion of fine aggregate 1.5 in M20 grade 0.5 is Red soil. According to the mix proportion of fine aggregate 1 in M25 grade 0.5 is Red soil. The Mineral admixture-(fly ash) is used in the study of red soil with mineral admixture 9 in concrete as a partial replacement of cement 7. Fly ash is replaced with cement in various percentages from 5% to 30% for both the M20 and M25 grades of concrete. The Mixing of Material for red soil with mineral admixture in concrete, Mix design method is very important to get the accurate result for the mix proportion of concrete. The mix design method followed in this study is called as precise analytical method by Dr.S.Alexander and he is the consultant of this project work. The mix design for red soil with mineral admixture 2 in concrete for 1:1.5:3 & 1:1:2 mix proportion is done for concrete mix. For the specimens which is to be casted and tested, same mix proportion is used for it. In the mix proportion of 1:1.5:3 1-cement, 1.5-fine aggregate is splitted as 1 and 0.5 (1 is sand and 0.5 is red soil), 3 is editor@iaeme.com

4 James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander coarse aggregate. In the mix proportion of 1:1:2 1-cement, 1-fine aggregate is splitted as 0.5 and 0.5 (0.5 is sand and 0.5 is red soil), 2 is coarse aggregate. Figure 1 Red Soil, River sand and fly ash (Left to Right) 3. METHODOLOGY The Stress-strain test for red soil with mineral admixture in concrete 6, the standard mold of size 150mm 300mm is used for casting. Curing is done for 28days for concrete Cylinders and the stress-strain test is done in universal testing machine (UTM) as per IS 516:1959 for the partially replaced samples. The cylinder specimens are loaded in the utm machine and gradually the load is applied till it reaches its maximum bearing point, the stress strain graph and load & deflection values are noted down from the system which is connected with utm machine. Maximum load is applied and peak load and peak deflection is obtained from it. The Modulus of elasticity test is also done through the same standards which is of the standard cylinder mold of size 150mm 300mm is used for casting. Curing is done for 28days for concrete Cylinders and the Modulus of elasticity test is done in universal testing machine (UTM) as per IS 516:1959 for the partially replaced samples. The modulus of elasticity is found for various fly ash replacement with red soil cement 9 concrete and also the modulus of elasticity for various codal provisions are found out as per different codes. The Toughness test follows the same standard of the standard mold of size 150mm 300mm is used for casting. Curing is done for 28days for concrete Cylinders and the Toughness test is done in universal testing machine (UTM) as per IS 516:1959 for the partially replaced samples 7. The toughness is found through area under maximum stress and strain and simpsons rule was followed for calculating the toughness. The Microstructural investigation 1 of Plain concrete samples and red soil cement concrete samples are tested In scanning electron microscope and in the x-ray diffraction pattern, the samples are in powder form which is on nano particles for testing under microsope & also under x-ray RESULT STRESS STRAIN Stress =, / or MPa and Strain = No unit. Stress-It is a force that tends to deform the body on which it acts per unit area. Strain-Measure of the extent to which a body deforms under stress. In strain The length changes when the load is applied to the cylinder specimen. The load and deflection is obtained from test results in system which is connected to the universal testing machine and stress strain calculations are done from the load and deflections values editor@iaeme.com

5 Influence of Mineral Admixture On Elastic Behaviour of Red Soil Cement Concrete Under Flexural Loading Table 3 Stress strain for concrete cylinders (5% fly ash replacement) Trial No. M20 Grade 5% Fly ash replacement M25 Grade 5% Fly ash replacement Stress (MPa) Strain Stress (MPa) Strain Trial Trial Trial Figure 2 Stress strain of cylinder for M20 grade concrete of 5% fly ash replacement Figure 3 Stress strain of cylinder for M25 grade concrete of 5% fly ash replacement The stress strain of M25 grade 5% fly ash replacement in red soil cement concrete shows Table 4 Stress strain for concrete cylinders (10% fly ash replacement) M20 Grade 10% Fly ash replacement M25 Grade 10% Fly ash replacement Trial No. Stress (MPa) Strain Stress (MPa) Strain Trial Trial Trial editor@iaeme.com

6 James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander Figure 4 Stress strain of cylinder for M20 grade concrete of 10% fly ash replacement Figure 5 Stress strain of cylinder for M25 grade concrete of 10% fly ash replacement The stress strain of M25 grade 10% fly ash replacement in red soil cement concrete shows Table 5 Stress strain for concrete cylinders (15% fly ash replacement) Trial No. M20 Grade 15% Fly ash replacement M25 Grade 15% Fly ash replacement Stress (MPa) Strain Stress (MPa) Strain Trial Trial Trial editor@iaeme.com

7 Influence of Mineral Admixture On Elastic Behaviour of Red Soil Cement Concrete Under Flexural Loading Figure 6 Stress strain of cylinder for M20 grade concrete of 15% fly ash replacement Figure 7 Stress strain of cylinder for M25 grade concrete of 15% fly ash replacement The stress strain of M25 grade 15% fly ash replacement in red soil cement concrete shows Trial No. Table 6 Stress strain for concrete cylinders (15% fly ash replacement) M20 Grade 20% Fly ash replacement M25 Grade 20% Fly ash replacement Stress (MPa) Strain Stress (MPa) Strain Trial Trial Trial Figure 8 Stress strain of cylinder for M20 grade concrete of 20% fly ash replacement Figure 9 Stress strain of cylinder for M25 grade concrete of 20% fly ash replacement editor@iaeme.com

8 James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander The stress strain of M25 grade 20% fly ash replacement in red soil cement concrete shows Trial No. Table 7 Stress strain for concrete cylinders (25% fly ash replacement) M20 Grade 25% Fly ash replacement M25 Grade 25% Fly ash replacement Stress (MPa) Strain Stress (MPa) Strain Trial Trial Trial Figure 10 Stress strain of cylinder for M20 grade concrete of 25% fly ash replacement Figure 11 Stress strain of cylinder for M25 grade concrete of 25% fly ash replacement The stress strain of M25 grade 25% fly ash replacement in red soil cement concrete shows Trial No. Table 8 Stress strain for concrete cylinders (30% fly ash replacement) M20 Grade 30% Fly ash replacement M25 Grade 30% Fly ash replacement Stress (MPa) Strain Stress (MPa) Strain Trial Trial Trial editor@iaeme.com

9 Influence of Mineral Admixture On Elastic Behaviour of Red Soil Cement Concrete Under Flexural Loading Figure 12 Stress strain of cylinder for M20 grade concrete of 30% fly ash replacement Figure 13 Stress strain of cylinder for M25 grade concrete of 30% fly ash replacement The stress strain of M25 grade 30% fly ash replacement in red soil cement concrete shows 5. MODULUS OF ELASTICITY Young s modulus E =!"#, The young s modulus is found from the stress-strain graph and!"$%& the average value is calculated for every trial values. The modulus of elasticity is one of the important properties of concrete. These are the basic parameters for computing deflection in unreinforced concrete structures. Various countries have been established their design codes based on the modulus of elasticity of plain concrete. In this study, modulus of elasticity as per different codes are determined for M20 and M25 grades of red soil mixed concrete with mineral admixture editor@iaeme.com

10 GRADE OF CONCRETE James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander Table 9 young s modulus for concrete cylinders FLY ASH REPLACEMENT % MODULUS OF ELASTICITY TRIAL 1 (MPa) TRIAL 2 (MPa) TRIAL 3 (MPa) AVERAGE E (MPa) M M Figure 14 Modulus of elasticity for M20 & M25 grade concrete cylinders The modulus of elasticity for grade M20-10% and M25-5% fly ash replacement in red soil cement concrete shows Figure 15 Modulus of elasticity as per different codes for M20 & M25 cylinders The modulus of elasticity as per different code shows in European code editor@iaeme.com

11 Influence of Mineral Admixture On Elastic Behaviour of Red Soil Cement Concrete Under Flexural Loading 6. TOUGHNESS The area under maximum stress and maximum strain is called as toughness. The toughness of concrete is measured for M20 and M25 grade of red soil cement concrete for various fly ash replacements. Simpsons rule is used to calculate the toughness of concrete. Table 10 Toughness for M20 grade of concrete for various fly ash replacements M20-5% M20-10% M20-15% M20-20% M20-25% M20-30% Figure 16 Toughness for M20 grade of concrete for various fly ash replacements The toughness for M20 grade 5% fly ash replacement in red soil cement concrete shows Table 11 Toughness for M25 grade of concrete for various fly ash replacements M25-5% M25-10% M25-15% M25-20% M25-25% M25-30% Figure 17 Toughness for M25 grade of concrete for various fly ash replacements The toughness for M25 grade 10% fly ash replacement in red soil cement concrete shows

12 James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander Figure 18 Scanning electron microscopic image of plain concrete Figure 19 Scanning electron microscopic image of Red soil cement concrete 7. SCANNIG ELECTRON MICROSCOPE IMAGE More amount of calcium-silicate-hydrate (C-S-H) gel and Calcium hydroxide Ca(OH) plate has formed only in Red soil cement concrete. Red soil cement concrete has a dense formation of (C-S-H) gel and Ca(OH) plate as shown in fig 30. Plain concrete has more amount of voids and it is less in (C-S-H) gel as shown in fig 29. Red soil cement concrete has less amount of voids as compared to plain concrete. Plain concrete does not have a dense formation in (C-S-H) gel and it is less in Ca(OH) plate editor@iaeme.com

13 Influence of Mineral Admixture On Elastic Behaviour of Red Soil Cement Concrete Under Flexural Loading Figure 20 X-ray diffraction pattern of plain concrete and Red soil cement concrete 8. X-RAY DIFFRACTION PATTERN The graphs are shown between 20 and 70 for red soil cement concrete and plain concrete samples. SiO2, Ca(OH)2, CnS, CaCO3, CaO and Al2O3 are the chemical compounds identified from the XRD results. SiO2 is in the peak of 27.3, CnS is in the peak of 21.6, CaCO3 is in the peak of 43.1, CaO is in the peak of 34.7, Ca (OH) 2 is in the peak of 31.8, Al2O3 is in the peak of In plain concrete, Al2O3 is completely disappeared but in red soil cement concrete Al2O3 is still present in it. In Red soil cement concrete, significant peaks are in SiO2, CnS & CaCO3 which shows major difference between plain concrete and red soil cement concrete. This is the cause for the increase in strength for red soil cement concrete than the plain concrete. 9. CONCLUSION The following test results of various tests explains that the Red soil mixed concrete with mineral admixture fly ash is comparatively higher in M25 than M20 grade of concrete mix. In stress strain test, for M20 grade of red soil mixed concrete with mineral admixture fly ash which is of 5% fly ash replacement, the maximum stress is MPa and strain is but in M25 grade of red soil mixed concrete with mineral admixture fly ash which is also of 5% fly ash replacement the maximum stress is MPa and strain is In Modulus of elasticity test from stress strain graph, for M20 grade of red soil mixed concrete with mineral admixture fly ash which is of 10% fly ash replacement, the maximum E is MPa but in M25 grade of red soil mixed concrete with mineral admixture fly ash which is of 5% fly ash replacement, the maximum E is MPa. In Modulus of elasticity test as per different codal provisions, red soil mixed concrete with mineral admixture fly ash, the maximum Ec is from Euro code which has shown the significant increase in Ec from 5% and 10% fly ash replacement for M20 and M25 grades of concrete. (M20-5%)= , (M20-10%)=38874, (M25-5%)= , (M25-10%)= In Toughness test, M20 grade of red soil mixed concrete with mineral admixture fly ash of 5% shows maximum toughness and in M25 grade of red soil mixed concrete with mineral admixture fly ash of 10% shows maximum toughness editor@iaeme.com

14 James Alexander. S, Prof. Antony Godwin and Dr.S.Alexander In SEM and XRD tests it shows that the red soil cement concrete is better than plain concrete by its major elements of SiO2, CnS & CaCO3.This is the cause for the increase in strength for red soil cement concrete than the plain concrete. If this red soil cement concrete is used in RCC, then there will be no corrosion in steel because of its imperviousness as proved in the previous study as well as it is good in elasticity behaviour with the optimum replacement of 5% to 10% fly ash replacement. Red soil can be used in RCC as well as prestressed concrete. Follow of action is to be done in research for shell structures, prestress and RCC to confirm that red soil can be used in multi storied building. ACKNOWLEDGMENT I wish to express my sincere thanks to Dr.S.Alexander (consultant) for his encouraging and a mindful support and it s a great privilege for me to work with him in this project work and I wish my heartful thanks to my guide Prof. Mr.Antony Godwin for his firm guidance and I thank KARUNYA UNIVERSITY for providing me the timely needs to complete my project work. REFERENCES [1] M.N.Uddin, V.Saraswathy & P. Elumalai An Experimental Investigation of Red Soil Based Geopolymer Mortar Without Portland cement International Journal of Scientific & Engineering Research, Volume 6, Issue 5, May [2] Ashok Raajiv.v.s, Augustine Maniraj Pandian Experimental investigation on the effects of using soil as a replacement of sand in concrete ICETSH-(2015), page: [3] Sunkara yashwant, Someswara Rao b, Venkata Rao G. Experimental studies on laterite soil stabilized with cement and aggregate, Indian Journal of Research Engineering and Technology Vol. 04, August (2015). [4] Joshua, Amusan, Fagbenle O.I & kukoyi P.O, Effects of partial replacement of sand with lateritic soil in sandcrete blocks, Covenant Journal of Research in Built Environment vol.1, March (2014). [5] Prakash.S, Rajesh kumar.k, Sakthi.S & Shembiang Marthong, Kumutha & Vijai k., Feasibility study on utilisation of laterite soil for stabilized earth blocks, Research Desk (2013), Jul-Sep (2) [6] Tarh Reema, Ajanta Kalita, Strength characteristics of red soils blended with fly ash and lime, International Journal of Innovative Research in Science, Engineering and Technology, Vol. 4(3), March (2014). [7] K. Mahendran and N. P. Vignesh, Utilization of hypo sludge for the stabilization of red soils along with cement and molasses Indian journal of science and technology-january (2016). [8] sai darshan.t.r and mayanaik.n, Effect of chemical admixtures on the engineering properties of red earth treated with cement iosr journal of mechanical and civil engineering (iosr-jmce)-feburaury (2014). [9] Ajanta kalita and Baleshwar singh, Experimental study on strength behaviour of cement blended soil-fly ash mixtures Indian geotechnical soceity (igc) (2009) editor@iaeme.com