STUDY NOTES FOR PG STUDENTS, RESEARCH STUDENTS, Study notes of Law

Download STUDY NOTES FOR PG STUDENTS, RESEARCH STUDENTS and more Study notes Law in PDF only on Docsity! EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME CHAPTER 1 INTRODUCTION Cement and natural river sand are becoming scare resources all over the world because of its increasing demands day by day. The construction activities have increased in almost all the developing countries of the world. There always has been great effort in improving the quality and standards of the properties of concrete as a construction material. Concrete is a mix of ingredient of cement, fine aggregate, coarse aggregate and water. It can be molded into any shape in plastic stage. It is the composite material, most used for the construction of multistory buildings and various infrastructure developments area particularly in developing countries like India is more. The relative quantity of ingredients controls the property of concrete in wet stage as well as in hardened stage. Before two or three decades ago, the production of concrete for construction of building with OPC with the ease of availability of concrete ingredients irrespective of quality was in practice without considering the future of concrete structure. Now with the passage of time, in the modern era, investigations since last two to three decades made by Engineers and Scientists keeping in view the structural stability of structure which needs quality concrete with improved strength, durability and other characteristics of concrete. The demand of these characteristics derive the search for supplementary constituent materials. Search for any suitable material in partial replacement of cement and sand which is universally sustainable development and lowest possible environmental impact. Cement concrete is the most construction material today. We can say that we are living in the era of concrete. In general, fine aggregate used in concrete production of concrete is Natural River Sand. Now a days, natural resources like River Sand is exhausting gradually around the world. So, from the view point of protection of environment and saving natural resources, the construction industries are looks for the various alternative constituent materials for concrete production. So, there is a need for the replacement of cement and sand in the concrete. In India, major portion of electricity is generated by burning coal resulting in the formation of ash. The ash content comes from the burning of coal has to be disposed as either in dry state or in wet state available open areas nearer the plant. These are open to atmosphere causes environmental pollution and loss of productive land. Substantial use of industrial by products save the cost and energy in addition to meet the requirement of environmental awareness. In the geourney of research, Silica fume, Fly ash, Ground granulated blast furnance slag etc are found most commonly used cementatious 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 1 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME materials in partial replacement of cement. The use of Silica fume as a cementatious material has increased in recent years because when mixed in certain proportions it enhances the properties of both fresh and hard concrete like durability, strength, permeability and compressive, flexural and tensile strength. 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 2 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME > Ahmad Farhan Hamzah et al (2015) studied on Fresh Characteristic and Mechanical Compressive Strength Development of Self-Compacting Concrete Integrating Coal Bottom Ash as Partial Fine Aggregates Replacement. The experimental works to study the effect of use of coal bottom ash as a partial replacement of fine aggregates in self-compacing concrete (SCC). The compressive strength properties studied instead of fresh characteristic of mixtures. The SCC mixtures were produced by three different water cement ratios (0.35, 0.40 and 0.45) and coal bottom ash as a replacement of fine aggregates in varying percentages of 0%, 10%, 15%, 20%, 25% and 30%. The fresh properties were investigated by slump flow, T500 spread time, sieve segregation and L-box test in order to evaluate its self- compatibility. It can be concluding that the filling and passing ability of SCC mixture decreased when the amount of coal bottom ash content increased. The compressive strength development for various percentages replacement of fine aggregates with coal bottom ash was conducted at 28, 90 and 180 days. It is clearly noticeable the progress of compressive strength on intensification of water cement ratio at different curing ages. The increase of water cement ratio decreased the compressive strength for all percentages of coal bottom ash at all ages > Aswathy P.U et al (2015) studied on the Behaviour of Self Compacting Concrete by Partial Replacement of Fine Aggregate with Coal Bottom Ash. This study presents the experimental investigation carried out to study the behavior of self-compacting concrete incorporating coal bottom ash at different replacement level of fine aggregate. To find the optimum replacement level the replacement levels of coal bottom ash to fine aggregate is set up from 5 - 30% at 5% increment. Then the optimum mix was subjected to variations (increment and decrement in coal bottom ash in optimum mix). The fresh and hardened properties such as compressive strength, split tensile strength, flexural strength and modulus of elasticity of the concrete at the age of 28 days of curing were conducted for all the variations. Results shows that the strength of the concrete with coal bottom ash increased up to replacement level of 10%.This show that bottom ash are used as supplementary cementitious materials, having the pozzolanic reactivity. 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 5 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME Based on the work of various researchers it was seen that cement can be replaced by silica fume for upto 15% and bottom ash can be a suitable material for replacement of concrete mix. The compressive strength for 7, 28, 56 and 90 days was increased up to 15-20% replacement of Bottom Ash. So in this work experimental investigation carried out by replacing cement by silica fume upto 20% and Sand by Bottom ash for various ranges such as 0%, 20%, 40%, 60%, 80% and 100%. 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 6 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME Gt CHAPTER -3 OBJECTIVES OF THE WORK Concrete is a mixture of cement, aggregate and water. Sand is normally used fine aggregate that is derived from river banks. The utilization of river sand in constructions is also high due to its most use in concrete. In developing countries the usage of river sand is pretty high due to rapid infrastructural development which results in shortage of sand. Therefore, in developing countries identify substituent material to replace the natural sand in concrete. The utilization of waste materials it will decreases in environmental load & waste management cost, reduce the cost of production as well as concrete quality gets increasing. Now a day’s river sand is very costly material because of more constructional activities. Due to this situation, investigate began for alternative material to natural sand. > The main objective of this investigational work is to determine the effect of partial replacement of natural sand by Silica fume and Bottom Ash on the properties of concrete. > The percentage substitution of cement by Silica fume adopted in this experimentation is 20% and natural sand by Bottom Ash for 0%, 20%, 40%, 60%, 80% and 100%. > The purpose is to study the possibility of using SF and BA to make a lightweight, high. performance and environmentally friendly concrete. > The effect of SF and BA on the workability characteristics are studied through slump, compaction factor and vee-bee tests. > The strength characteristics such as compressive, tensile, flexural, shear and impact strengths are studied. The work is carried out for M30 grade of concrete. 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 7 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME Locally obtainable crushed aggregates confirming to IS: 383-1970 is used in this project work of size 20mm below. The coarse aggregate specific gravity was found to be 2.68. Fig 4.3 : Locally available crushed aggregate Table 4.4 : Physical properties of coarse aggregate Property Results Particle shape, size Angular 20mm down size Fineness modulus of 20mm 6.80 aggregate Specific gravity 2.70 4.1.4 Silica Fume 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 10 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME SS Silica fume is a very fine noncrystalline material produced in electric arc furnace as a byproduct of silicon metal or ferrosilicon alloys. Silica fume has been known to us with different names such as micro silica, silica dust and condensed silica fume. Silica fume has a property that it behaves as a pozollana as well as cementatious material. One of the the most beneficial uses for silica fume is in concrete. Silica fume pozzolanic materials is found most suitable industrial product as to be used in concrete as partial replacement of cement. The optimum silica fume replacement percentage for obtaining maximum 28-days strength of concrete ranged from 5 to 20%. When pozzolanic materials are incorporated to concrete, the silica present in these materials react with the calcium hydroxide released during the hydration of cement and forms additional calcium silicate hydrate (C-S-H), which improve durability and the mechanical properties of concrete. When the fine pozzolana silica fume particles are added to the paste, a heat of hydration is observed resulting in the formation of pozzolanic material and calcium hydroxide. Due to large surface area silica fume gets densed packed in the paste of cement and aggregate reducing the wall effect in the transition zone between the paste and aggregate. Concrete having optimum percentage of silica fume shows increasing strength and durability of concrete. Fig 4.4 : Silica fume The physical properties of silica fume are as follows- Da 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 11 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME > Diameter of silica fume is 0.1 micron to 0.2 micron. > Surface area is in the range of 20,000-30,000 m’/kg. > Density varies from 150 to 700 kg/m*. The chemical properties of silica fume are as follows- > Silica fume contains more than 90% of silicon dioxide (Sioz). > Other constituents are carbon, sulpher and oxides of aluminium, iron calcium, magnesium, sodium and potassium. The use of silica fume in concrete mix has engineering potential and economic advantage. The use of silica fume will not effect the weight of concrete. Silica fume will produce a much less permeable and high strength concrete. Table 4.5 : Physical properties of silica fume Specific gravity 2.3 Mean grain size 0.15 colour Light to dark gray Table 4.6 : Chemical properties of silica fume (%) Silicon dioxide (SiOz) 85 Aluminium oxide (Al,03) 1.12 Tron oxide (Fe203) 1.46 Calcium oxide (CaO) 0.2-0.8 Magnesium oxide (MgO) 0.2-0.8 Sodium oxide (NaO) 0.5-1.2 Potassium oxide (KO) 0.5-1.2 Loss on ignition <0.6 4.1.5 Bottom Ash 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 12 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME The mix design procedure adopted to obtain a M30 grade IS 10262- 2009. The specific gravities of the materials used are as tabulated. Mix Design for M30 grade concrete A- Stipulations for proportioning a) Grade designation = M-30 b) Types of cement = OPC43 grade confirming (IS:10262-2009) c) Maximum nominal size of aggregates = 20 mm (Table 5 of IS : 456-2000) d) Minimum Cement content = 320 Kg/m? e) Maximum water-cement ratio = 0.45 f) | Workability = 100mm (slump) g) Exposure condition = Severe h) Method of concrete placing = Conventional i) Degree of supervision = Good j) Type of aggregate = Crushed angular aggregate B- Test data for materials a) Cement used = OPC43 grade confirming (IS:10262-2009) b) Specific gravity of cement = 3.15 c) Cement replacing material = Silica fume d) = Specific gravity of 1) Coarse aggregate = 2.70 2) Fine aggregate = 2.60 The design steps are as follows Step 1: Determination of target strength for mix proportioning Fu=fa + 1.65S Where, Fux = Target mean compressive strength at 28 days fa = Characteristic compressive strength at 28 days S = Standard deviation From IS 456-2000, Table 8, standard deviation, S = 5 therefore target strength = 30+(1.65X5) = 38.25 N/mm? Step 2 : Selection of Water-Cement ratio As per IS 456-2000, Table 5, W/C Ratio = 0.45 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 15 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME Adopt Water-Cement Ratio = 0.45 Step 3: Selection of water content Referring to IS 10262-2009, Table 2, for coarse of size 20mm aggregate Maximum water content = 186 litre Therefore estimated water content = 186 + (6/100)186 = 197 litre Step 4: Calculation of Cement content Water-Cement Ratio = 0.45 Cementitious material (Cement+S.F.) = 197/0.45 = 438 Kg/m* Minimum Cement content for severe exposure condition = 320 Kg/m? Hence the cement content is adequate. Increase of 10% Cementitious material content Cementitious material content = 438X1.10 = 481.8 Kg/m* Step 5: Determination of volume of coarse and fine aggregate Referring to IS 10262-2009, Table 3, volume of coarse aggregate per unit volume of concrete corresponding to a maximum size of coarse of 20mm and fine aggregate corresponding to grading zone IJ and water-cement ratio of 0.45. Volume of coarse aggregate = 0.62 Volume of fine aggregate = 1-0.62 = 0.38 Step 6: Mix calculation The mix calculation per unit volume of concrete shall be as follows. a) Volume of concrete = 1m* b) Volume of cement = (Mass of cement/specific gravity of cement)/1000 = (481.80/3.15)X(1/1000) = 0.153 m* c) Volume of water = (Weight of water/specific gravity of water)/1000 = (197/1)X(1/1000) = 0.197 m* d) Volume of all in aggregate = [a-(b+c)] = [1-(0.153+0.197)] = 0.65 m* e) Mass of coarse aggregate = (d)xVolume of CAxSpecific gravity of CAx1000 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 16 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME f) Mass of fine aggregate = 0.65X0.62X2.70X 1000 1088.2 Kg (d)xVolume of FAxSpecific gravity of FAx1000 0.65X0.38X2.60X 1000 = 642.25 Kg Table 4.9 : Material ratios Materials Qtty Ratio Cement 481.80 1 Fine aggregate 642.25 1.33 Coarse aggregate 1088.20 2.26 Water-Cement ratio 0.45 0.45 Total volume = 0.33 m? Add 10% extra volume = 0.36 m? Density of concrete = 2500 Kg/m* Therefore volume of concrete = 0.36X2500 = 900 Kg Step 7 : Quantity Calculation Cement = (900X1)/(1+1.33+2.26) = 196.08 Kg Fine Aggregate = (900X1.33)/(141.33+2.26) = 260.78 Kg Coarse Aggregate = (900X2.26)/(1+1.33+2.26) = 443.14 Kg Water = (900X0.45)/(1+1.33+2.26) = 88.24 Ltr Silica Fume at 20% by weight of cement = 39.22 Kg Therefore cement qtty = 156.86 Kg Saving in cement qtty = 39.22 Kg 4.3 Mixing and casting of specimens 4" Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 17 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME 4.4 Workability test on fresh concrete 4.4.1 Workability by Slump cone test The below procedure is adopted to carry out the slump cone test. > Place the concrete mix in the cleaned slump cone mould in four layers. Each layer is 1/4th of the height of the mould. Each layer tamped with 25 blows the blows are spread uniformly over the entire surface. For second and subsequent layer tamping rod should penetrate to the under lying layer. Strike of the top with a tamping rod or trowel so that mould is exactly filled. Raise the slump cone by using handle of instrument vertically and bring it on the slump cone top. Measure the height between the top of the slump cone and handle, note this as H1. Lower the handle to the sides of the slump cone and lift the cone slowly without disturbing the concrete. Concrete starts settling, as soon as the settlement stops. Raise the handle and bring it on the top of the unsupported concrete. Measure the vertical height between the handle and the top of concrete, call this as H2. Slump = (H2-H1) in mm. The slump cone test apparatus dimensions and types of slump produced are shown in fig ory | i {slump ‘ slump 1 iL Ll i At Least. . | Collapse Shear True slump Types of slump Fig 4.6 : Typical slump cone test specimen 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 20 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME 4.4.2 Workability by Compaction Factor test The below procedure is adopted to carry out the compaction factor test. > The internal surface of the hoppers and cylinder shall be thoroughly clean and free from superfluous moisture and any set of concrete commencing the test. The sample of concrete to be tested shall be placed gently in the upper hopper using the scoop. The trap door shall be opened immediately after filling or approximately 6 min after water is added so that the concrete fails into the lower hopper. During this process the cylinder shall be covered. Immediately after the concrete has come to the rest the cylinder shall be uncovered, the trap door of the lower hopper opened and the concrete allowed falling to into the cylinder. For some mixes have a tendency to stick in one or both of the hoppers. If this occurs the concrete shall be helped through by pushing the tamping rod gently into the concrete from the top. The excess of concrete remaining above the level of the top of the cylinder shall then be cut off by holding a trowel in each hand, with the plane of the blades horizontal, and moving them simultaneously one from each side across the top of the cylinder, at the same time keeping them pressed on the top edge of the cylinder. The outside of the cylinder shall then be wiped clean. This entire process shall be carried out at a place free from vibration or shock. Determine the weight of concrete to the nearest 10 g. This is known as "weight of partially compacted concrete", Wp. Refill the cylinder with concrete from the same sample in layers approximately 50 mm depth. The layers being heavily rammed with the compacting rod or vibrated to obtain full compaction. The top surface of the fully compacted concrete shall be carefully struck off and finished level with the top of the cylinder. Clean up the outside of the cylinder. Determine the weight of concrete to the nearest 10 g. This is known as "weight of fully compacted concrete", Wf. The compacting factor, Fc can be calculated as follows: a "weight of partially compacted concret The compacting factor = "weight of fully compacted concrete", 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 21 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME Conical Hopper Compacting Factor Apparatus Fig 4.7 : Typical compaction factor test specimen Da 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 22 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME Fig 4.12 : Casting of specimens Fig 4.13 : Demoulded specimens Da 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 25 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME 4.5 Task to be perform After completion of 28 days curing period work to be perform are : 1. Compressive strength test on cubes, 2. Split tensile strength test on cylinders, 3. Flexural strength test on beams, 4. Shear strength test on L-Shape shear specimens, 5. Impact strength test. 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 26 EFFECT OF REPLACEMENT OF SAND BY BOTTOM ASH AND CEMENT BY SILICA FUME Gt REFERRENCES IS Codes 1. IS 456 : 2000 Indian Standard Plain and Reinforced concrete — Code of practice 2. IS 10262 : 2009 Indian Standard Concrete Mix Proportioning — Guidelines. Text Books 3. Debabrata Pradhan, D. Dutta, “Effects of Silica Fume in Conventional Concrete” Int. Journal of Engineering Research and Applications Vol. 3, Issue 5, Sep-Oct 2013 pp.1307-1310 4. Gagandeep, Kshipra Gupta, “BOTTOM ASH AS PARTIAL SAND REPLACEMENT IN CONCRETE- A REVIEW” International Journal of Latest Research In Engineering and Computing (IJLREC) Volume 5, Issue 2 , Page No. 13-16 March-April 2017 5. Vikas R Nadig, Sanjith J, Ranjith A, Kiran B M, “Bottom Ash as Partial Sand Replacement in Concrete- A Review”, IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) Volume 12, Issue 2 Ver. VI (Mar - Apr. 2015), PP 148-151 6. Praveer Singh, Mohd. Afaque Khan, Abhishek Kumar, “The Effect on Concrete by Partial Replacement of Cement by Silica Fume: A Review”, International Research Journal of Engineering and Technology (IRJET), Volume: 03 Issue: 03 Mar-2016 4® Sem M.Tech. (Str. Engg.) Dept. of Civil Engg. Govt. Engg. College, HAVERI - 581 110 Page 27