CHAPTER-3 PROGRAMME 121

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1 120 CHAPTER-3 TESTS ON MATERIALS USED IN THE EXPERIMENTAL PROGRAMME General Cement Fine Aggregate Specific Gravity of Fine Aggregate Bulk Density of Fine Aggregate Fineness Modulus of Fine Aggregates Coarse Aggregate Specific Gravity of Coarse Aggregate Bulk Density of Coarse Aggregate Fineness Modulus of Coarse Aggregate Metakaolin Natural Rubber Latex Steel Fibers Water Closure 131

2 121 CHAPTER-3 TESTS ON MATERIALS USED IN THE EXPERIMENTAL PROGRAMME 3.1 General: In order to achieve the objectives mentioned in Chapter 1, a detailed experimental investigation on Metakaolin based Natural Rubber Latex Modified Fibre Reinforced High Performance Concrete (NRLMFRHPC) has been planned. Metakaolin is used as a mineral admixture; Natural rubber latex polymer is used as an additive. In the production of HPC polymer based chemical super plasticizers are generally used to improve the flow properties and to reduce the water-binder ratio. However in the present work, it is proposed to use the naturally available polymer i.e. Natural Rubber Latex (NRL) in the production of HPC and steel fibres of an aspect ratio 50 are added to improve the strength and ductility properties. The physical properties of each material which are used in the research program are presented in this chapter. The various materials used in this investigation are cement, fine aggregate, coarse aggregate, Metakaolin, Rubber Latex and water. In this Chapter, the test conducted on each material to find out its suitability is explained in detailed manner. 3.2 Cement: Ordinary Portland cement of 53 grade conforming to IS: standards has been procured and following tests have been carried out according to IS: a) Specific gravity of Cement b) Normal Consistency of Cement

3 122 c) Initial and Final setting time of Cement d) Compressive Strength of Cement. The results of above tests are presented in Table 3.1. Table 3.1 Result of tests on cement S. No Test 1 Fineness of Cement a) Sieve test b) Blains specific surface Area Experimental values 4.52% 315 m 2 /kg 2 Specific gravity Normal consistency 33% -- 4 Setting time Initial setting time Final setting time 5 Compressive Strength at 3 days 7 days 28 days 64 min 410 min 30.4 N/mm N/mm N/mm 2 Suggested values as per I.S specification < 10.0 % 225m 2 /kg Min 30 min Max 440min 27.0 N/mm N/mm N/mm Fine aggregate: The sand which is used in this investigation is confirming to grading zone II of Table 4 of IS and has been collected from the locally available river chitravathi. The weight of fine aggregate was 40% of the total aggregate and has been maintained as constant throughout the experimental work. Following tests have been carried out as per the procedure given in IS 383(1970) and the results are shown in the below mentioned Tables 3.2(a) to 3.2(c)

4 123 a) Specific Gravity b) Bulk Density c) Grading d) Fineness Modulus Specific Gravity of fine Aggregates: Specific gravity of fine aggregate has been determined using pycnometer test with the following formula. Three trials have been conducted and average specific gravity is considered. The details are presented in Table 3.2 (a). Formulae = (w 2 -w 1 ) /[(w 2 -w 1 )-(w 3 -w 4 )] Eqn.No. 3.1 w 1 =Wt of empty Pycnometer w 2 = Wt of Pycnometer + 1/3 rd of fine Aggregates w 3 = Wt of Pycnometer +1/3 rd of F.A +Water w 4 =Wt of Pycnometer + Wt of water full of Pycnometer. Table 3.2(a) Specific Gravity of Fine aggregates No of Trials w 1 w 2 w 3 w 4 G Trial Trial Trial Average Value of Sp.Gravity of Fine Aggregates= ( )/3=2.688

5 Bulk Density of Fine Aggregates: The bulk density of aggregate shows how densely the aggregate is packed when filled in a standard manner. It is measured by filling in a container whose volume is known and compacted in a standard procedure. The weight of aggregate gives the bulk density in Kg/m 3. The particle size distribution and particle size influences the bulk density. The bulk density of fine aggregates are determined and presented in 3.2 (c) Fineness Modulus of Fine Aggregates: The sieve analysis has been conducted to determine the FM and grading Zone of Fine Aggregates (FA). The details are given in Table 3.2 (b) and 3.2 (c). Table 3.2(b) Sieve analysis of fine aggregate S. No. I.S Sieve designation Weight retained (Gms) % of weight retained Cumulative% of weight retained mm mm mm Pan Total = Fineness Modulus = 2.77 % of Passing

6 125 Table 3.2(c) Physical properties of fine Aggregates S. No. Property Value 1 Specific gravity Fineness modulus Bulk density i) Loose ii) Compacted kn/m KN/m 3 4 Grading Zone II 3.4 Coarse aggregate: The locally available Crushed granite metal with 50% passing through 12.5mm and retained on 10mm sieve and 50% passing through 20mm and retained on 12.5mm sieve was used. The weight of coarse aggregate was 60% of the total aggregate. The following tests have been carried out as per the procedure given in IS [2] and the results are presented in Tables 3.3(a) to 3.3(c). a) Specific Gravity b) Bulk Density c) Grading d) Water absorption e) Flakiness index f) Elongation Index g) Crushing value h) Impact Value

7 Specific Gravity of Coarse Aggregates: Formulae = (w 2 -w 1 ) / [(w 2 -w 1 )-(w 3 -w 4 )] Eqn.No. 3.2 w 1 = Wt of empty Pycnometer w 2 = Wt of pycnometer+1/3 rd Coarse Aggregates w 3 = Wt of Pycnometer +1/3 rd of C.A +Remaining quantity of water w 4 = Wt of Pycnometer +Wt of water full of Pycnometer. Table 3.3(a) Specific Gravity of Coarse Aggregates No of Trials w 1 w 2 w 3 w 4 G Trial Trial Trial Average Value of Sp.Gravity of coarse Aggregates= ( )/3= Bulk Density of Coarse Aggregates: The bulk densities of coarse aggregates are determined in a loose and compacted state and the results are presented in Table 3.3 (c) Fineness Modulus of Coarse Aggregates: Sieve analysis was conducted to determine the fineness modulus of coarse aggregates and details are presented in Table 3.3 (b) and 3.3 (c).

8 127 Table 3.3(b) Sieve analysis of coarse aggregate S. No. I.S.Sieve size Weight retained % of weight retained Cumulative % of weight retained % of passing 1 20mm mm mm mm mm Fineness modulus = 6.99 Table 3.3(c) Physical properties of coarse aggregate S.NO Property Coarse aggregate 1 Specific gravity Bulk density Loose KN/m 3 Compacted kn/m 3 3 Water absorption 0.70% 4 Flakiness index 14.22% 5 Elongation index 21.33% 6 crushing value 21.43% 7 Impact value 15.50%

9 Metakaolin: The mineral Admixture Metakaolin is obtained from M/S KOAT MANUFACTURING COMPANY, Regd office at 49 shalin complex, VADODARA, GUJARAT, INDIA. The Metakaolin is in conformity with requirements of pozzolana. Various properties of Metakaolin as supplied by the manufacturer are presented in the Table 3.4(a) and 3.4(b). Table 3.4(a) Properties of Metakaolin S. No Property Value 1 Specific gravity Accelerated pozzolanic active index, % of control 89 3 Residue on 45 sieve, % Chemical Analysis, % Loss on ignition Silica (SiO 2 ) Iron oxide (Fe 2 O 3 ) Aluminium (Al 2 O 3 ) Calcium oxide (CaO) Magnesium oxide (MgO)

10 129 Table 3.4(b) Physical properties of Metakaolin S. No. Properties Metakaolin 1 Average particle size,µm Residue on 45 sieve, % B.E.T Surface area m²/gm 15 4 Pozzolana reactivity mg Ca (OH) Specific Gravity Bulk density (gm/lt) 300±30 7 Brightness 80±2 8 Physical form off-white powder 3.6 Natural Rubber Latex: The Natural Rubber latex is collected from ASSOCIATED LATEX (INDIA) LIMITED having its Administrative Office at P.B. NO.1117, Beach Road, Calicut and its properties are given by the supplier are presented in Table 3.5.

11 130 Table 3.5 Physical properties of Rubber latex S.No Property Rubber latex 1 Colour White 2 Total Solid Content (% By Weight) 61.5 Max 3 Dry Rubber Content (% By Weight) 60 Min 4 Non Rubber solid content 1.50 Max 5 KOH Number 0.55 Max 6 Ammonia content, NH3 % 0.70 Max 7 Mechanical stability time Volatile Fatty Acid Number 0.10 Max 9 Magnesium Content 8 10 ph 10.4 Min 11 Coagulum Content, % By Mass 0.01 Max 12 Sludge Content, % By Mass 0.01 Max 13 Copper content As ppm 5 14 IRON content As ppm 8 15 Particle size of Rubber latex 0.2 m 16 Specific Gravity of Rubber latex Steel Fibres: In this study crimped steel fibres are used, which are procured from STEWELS COMPANY from Nagpur (Maharashtra). The aspect ratio of fibre is 50 and the density is 7840 kg/m Water: Water is an important ingredient of concrete as it actively participates in the Chemical reaction with cement and it helps to form the strength giving Gel. The

12 131 quantity and quality of water is to be carefully selected for the test Conducted for this investigation. The water which is fit for drinking is fit for the Concrete. The water used in the investigation is free from all the acids and organic Substances. The clean potable water is used in the investigation. The Physical properties of water are shown in Table 3.6 Table3.6 Physical properties of water S. No Parameter Amount 1 ph Taste Agreeable 3 Appearance Normal 4 Turbidity (NT Units) 3 5 Color (Hazen Units) 2 6 Hardness (mg/l) 1 7 Sulphates (mg/l) Chlorides (mg/l) Closure: After knowing the physical properties of various materials which are tabulated in the above tables, casting the cubes of Metakaolin based Natural rubber latex modified fibre reinforcement concrete has been conducted in the laboratory. Tests on raw materials viz. cement, sand, coarse aggregate, Metakaolin, Natural rubber latex, steel fibre s and water have been conducted to confirm their suitability for use in concrete as per the procedures laid down in I.S codes. It is observed that all the materials satisfy the relevant provisions of Indian Standard Codes of practice.