experimental studies on high performance concrete using metakaolin
- 1. 240 International Journal of Research and Innovation (IJRI) International Journal of Research and Innovation (IJRI) EXPERIMENTAL STUDIES ON HIGH PERFORMANCE CONCRETE USING METAKAOLIN Y Raja Latha1 , Damera Ramachander 2 , 1 Research Scholar, Department of Civil Engineering, Aurora’s Technological and Research Institute, Hyderabad,India. 2 Associate professor, Department of Civil Engineering, Aurora’s Technological and Research Institute, Hyderabad,India. *Corresponding Author: Y Raja Latha, Research Scholar, Department of Civil Engineering, Aurora’s Technological and Research Institute, Hyderabad India. Published: April 22, 2016 Review Type: peer reviewed Volume: III, Issue : II Citation: Y Raja Latha, Research Scholar (2016) "EXPERI- MENTAL STUDIES ON HIGH PERFORMANCE CON- CRETE USING METAKAOLIN" GENERAL High performance of concrete (HPC) widely been used in recent years, not only for its increased compressive strength, improved durability and economic benefits, but also for its positive impact on the environment. Some organic compounds are used in the concrete. A new admixture called METAKAOLIN. Used to the two different grade of concrete. Designed with different percentage of Metakaolin and then its effects are observed in improving of compressive strength and also tensile strength of con- crete at the same reducing of cost for the concrete. General Introduction Researchers have studied on the effect of replacement of Portland cement by Metakaolin and also on fiber addition on the mechanical and durability properties of ordinary Portland cement concrete. The literature being reviewed is given under 4 sections. (1) Review of literature of concrete containing pozzolanic materials such as Metakaolin. (2) Review of literature of SFRC on impact resistance. (3) Review of literature of SFRC on workability, compres- sive strength, tensile strength and modulus of elasticity. (4) Review of literature of OPCC & SFRC on exposure to elevated temperatures. (5) Review of literature of OPCC on compressive strength, split tensile strength, flexural strength and modulus of elasticity when exposed to different thermal cycles. Forming Metakaolin The T-O clay mineral kaolinite does not contain interlayer water. The temperature of dehydroxylation depends on the structural layer stacking order. Disordered kaolinite dehydroxylates between 530 and 570 °C, ordered kaolin- ite between 570 and 630 °C. Dehydroxylated disordered kaolinite shows higher pozzolanic activity than ordered. The dehydroxylation of kaolin to metakaolin is an endo- thermicin nature due to the large amount of energy re- quired to remove the chemically bonded hydroxyl ions. Sequence of Operation The investigation was carried on M30 and M40 grade con- crete. Required quantities of materials are calculated Ce- ment, sand, Course aggregate and fly ash is thoroughly mixed in dry mixer manually so as to obtain uniform color. Then the required percentage of Adhesive (METAKAOLIN) is added to the water calculated for that particular mix, this water is added to the dry mix with a view of obtain uniform mix. The compaction factor test and slump cone test were carried out and the respective values were re- corded for all mixes. The molds with standard dimensions i.e., 150mm*150mm were kept on table vibrator and the concrete was pointed into the molds in 3 layers by poking with tampering rod and vibrated by table vibrator. The vibrator was used. Casting and Curing Of Test Specimens The specimens of Standard cubes (150mm x 150mm) standard prisms (100mm x 100mm x 500mm) and stand- ard cylinders (150mm x 300mm height) 48No, were caste. Cement was replaced by 0%, 20%, 25%, 30% for M30 and M40 mixes and they were caste. Curing The test specimen cubes, prisms and cylinders were stored in place, free from vibration in most air at 90% relative humidity and at a temperature of 270c+_ 20c for 24 hours. Hour from the time of addition of water to the dry ingredients. After 24 hours the specimens were de- molded and immediately immersed in clean, fresh water tank for a period of 28 days. Abstract In this present experimental investigation an attempt is made to the strength and behavior of the meta kaolin, super plasticiser and other chemicals on high performance concrete. Cement is replaced by 0%, 20% of Metakaolin by volume of concrete, thus resulting in the increase in strength. Super-plasticizer is used to increase the workability of concrete, increase the density and strength. It can permit the reduction in the water cement ratio up to 15%,.Dosage of super- plasticizer is 1.5% by weight of cement. 1401-1402
- 2. 241 International Journal of Research and Innovation (IJRI) TESTING PROGRAM Slump Cone Test Slump cone test is the most common test used to meas- ure the workability both in laboratory and in field. It is widely used because of ease in performing this test. It is not suitable method for very wet or very dry concrete and stiff mix.it does not measure all factors contributing to workability. The slump was measured in/mm. as shown in plate. Compactions Factor Test The test is more sensitive and precise than slump cone test. And this test is used to determine the workability of low water cement ratio concrete, more accurately. princi- ple of this test is based up on the measuring the degree of compaction achieved by a standard amount of work done by allowing the concrete to fall to a standard height. Test for Compressive Strength of Concrete On the date of testing i.e., after 28 days casting of the cube specimens were removed from the water tank and placed on flat surface for 10 minutes to wipe off the surface wa- ter and grit, and also removes the projecting fineness on the surface of the specimens. Before placing the speci- men in testing machine the bearing surfaces of the testing machine was wiped clean, and the cube specimen also cleaned. The cube specimen was placed in the machine of 2000KN capacity. The load was applied approximately 140kg/sq.cm/min until the resistance of the specimen to the increasing load to be sustained, was shown in plate. The compressive strength of specimen was calculated by dividing the maximum load applied on the specimen dur- ing the test by the cross sectional area of the specimen for which average of three values of three cubes and the individual variation is more than 15% of the average was observed. DISCUSSIONS OF TEST RESULTS According to investigation reports a part of comprehensive study intend to decrease the contribution of Metakaolin on concrete mixes M 30 and M40 with a w/c ratio of 0.4 and 0.36 and cement replacement levels from 0 to 20% the optimum Metakaolin replacement level and strength improvement of high performance of concrete have been decreased. COMPRESSIVE STRENGTH OF CONCRETE The test was carried out to obtain compressive strength of M30 and M40 grade of concrete. The compressive strength of high performance of concrete with OPC and metakaolin concrete at the age of 28 days and presented. There is a significant Improvement in the strength of concrete be- cause of the high pozzolanic nature of the METAKAOLIN and its void filling ability. It can be seen from the compressive strength of both the mixes M30 and M40 at 28 days age, with replacement of cement by METAKAOLIN was increased gradually up to an optimum replacement level of 20% and then de- creased. The maximum 28 day cube compressive strength of M30 grade with 20% of metakaolin was 50.65Mpsa and of M40 grade with 20 % was 68.91 Mpa. The compressive strength of M30 grade concrete with partial replacement of 20% replacement shows10% greater than the control concrete. The maximum compressive strength of concrete in combination with METAKAOLIN depend on two param- eters namely the replacement level, water content ratio. Sieve analysis of Fine aggregate (Weight of sample 1000g) S.L No IS Sieve Size Weight Retained (g) Cumu- lative weight retained Cumula- tive % weight retained (g) Cumula- tive % Passing 1 10mm 0.00 0.00 0.00 100.00 2 4.75mm 10.00 10.00 1.00 99.00 3 2.36mm 46.50 56.50 5.65 94.35 4 1.18mm 188.00 24.50 24.45 75.55 5 600mm 288.00 532.50 53.25 46.75 6 300mm 358.00 890.50 89.005 10.95 7 150mm 109.00 1000.00 100.00 0.00 Fineness modulus of sand = Σg/100 = 273.35/100 = 2.73 Sieve Analysis of coarse Aggregate ( Weight of sample 5000 g) S.L No IS Sieve Size Weight Retained (g) Cumu- lative weight retained Cumula- tive % weight retained (g) Cumula- tive % Passing 1 80mm 0.00 0.00 0.00 100.00 2 40mm 0.00 0.00 0.00 100.00 3 20mm 3376.50 3376.50 67.52 32.48 4 10mm 1385.00 4761.00 95.22 4.78 5 4.8mm 169.00 4930.00 98.60 1.40 6 2.4mm 70.00 5000.00 100.00 0.00 7 1.18mm 0.00 5000.00 100.00 0.00 8 600mm 0.00 5000.00 100.00 0.00 9 300mm 0.00 5000.00 100.00 0.00 10 150MM 0.00 5000.00 100.00 0.00 Fineness modulus of Coarse aggregate = Σg/100 = 761.1/100 = 7.61 Compressive Strength of Concrete for Percentages of M30 Mix Id 7 days 28 days 56 days 90days M0-C100 25.45 30.78 35.18 38.92 M5-C95 28 32.34 37.46 42.45 M10-C90 29.3 33.7 39.82 46.52 M15-C85 30.12 36.23 40.45 48.32 M20-C80 33.23 40.34 45.52 50.65 Compressive Strength of Concrete for M40 Mix Id 7 days 28 days 56 days 90days M0-C100 32.68 46.8 54.87 60.6 M5-C95 34.7 50.6 57.26 62.2 M10-C90 38.4 52.4 60.32 65.25 M15-C85 41.9 53.73 63.8 66.7 M20-C80 42.67 55.26 65.24 68.91
- 3. 242 International Journal of Research and Innovation (IJRI) compressive strength for different percentages of Metakaolin M30 compressive strength for different percentages of Metakaolin M40 Metakaolin Tests for compressive strength of concrete Based on Laboratory results the following conclusions are drawn. 1. Cement replacement by adding METAKAOLIN leads to increase in compressive strength up to 20% replacement for both M30 and M40 grades of concrete. Beyond 20% replacement compressive strength decreased. 2. There is a decrease in workability as the replacement level increases, and hence water consumption will be more for higher replacements. 3. From the present study it is concluded that the opti- mum replacement level of cement by Metakaolin is 20% for M30 and M40 grade of concrete. 4. The 28 days’ strength in respect of both grades of con- crete with 20% replacement of cement by Metakaolin is maximum. 5. The addition of METAKAOLIN has further increased initial 7 day and 28 days, 56 days’ strength as evident from the tables. These METAKAOLIN are causing 5-10% of increases in the 7,28,56 days’ compression in the presence of Metaka- olin. The maximum strength at 28 days is observed with 0.20% METAKAOLIN and 20% replacement of cement Me- takaolin APPENDIX-A Sample calculation of concrete mix proportion for M30 grade of concrete STEP 1 SELECTION FOR PROPORTIONING Grade designation : M30 Type of cement : OPC 53 grade conforming to IS 8112 Maximum normal size of aggregate : 20mm Minimum cement content :320Kg/cubic m Maximum water-cement ratio : 0.45 Workability :100mm (slump) Maximum cement content : 450Kg/cubic STEP 2 TEST FOR MATERIALS Cement used : OPC 53 grade conforming to IS8112 Specific gravity of cement : 3.15 Specific gravity of METAKAOLIN : 2.62 Specific gravity of 1) Coarse aggregate : 2.74 2) Fine aggregate : 2.74 Water absorption: 1) Coarse aggregate : 0.5percent 2) Fine aggregate : 0.1 percent STEP 3 TARGET STRENGTH FOR MIX PROPORTION Target strength= 40+1.65x5 = 48.25 N/mm2 STEP 4 SELECTION OF WATER-CEMENT RATIO minimum water -cement ratio =0.45 Based on experience, adopt water-cement ratio as 0.45 STEP 5 SELECTION OF WATER CONTENT For 20mm aggregate = 186 liters Estimated water content for 100mm slump =186+6/100 x186 =197 liters
- 4. 243 International Journal of Research and Innovation (IJRI) STEP 6 CALCULATIONS OF CEMENT CONTENT Water-content ratio = 0.45 Cement content = 197/0.45 = 437.7 kg/m for cementitious material content = 437.7x1.1= 481.4 kg/m3 minimum cement content for ‘severe’ exposure condition = 360 kg/m3 434 kg/m3 > 360 kg/m3 , hence, O.K. Water content = 197 kg/m3 So,water cement ratio = 197/481.4 = 0.40 METAKAOLIN @ 10% of total cementitious material content =481.4x10% = 48.41kg/m3 Cement (OPC) = 481.4-(48.41) = 432.9 kg/m3 STEP 7 PROPORTION OF VOLUME OF COARSE AG- GREGATE AND FINE AGGREGATE CONTENT In the present case water-cement ratio is 0.40. Therefore, volume of coarse aggregate is required to be increased to decrease the fine aggregate content. As the water-cement ratio is lower by 0.10, the proportion of volume of coarse aggregate is increased by 0.02(at the rate of -/+ 0.01 for every + 0.05 change in water-cement ratio). Therefore, corrected proportion of volume of coarse aggre- gate for the water-cement ratio of 0.40 = 0.62. Volume of coarse aggregate = 0.62 Volume of fine aggregate content = 1- 0.62 = 0.38 REFERENCES: 1.Text Books 1) N.Krishna Raju,” Design of Concrete Mixes”,Year 2005 2) A.M.Nevile,” Properties of concrete”ELBS with Long- man 1987 3) M.S.Shetty,” Concrete Technology”, Year 2008 4) A.R.Santhakumar,” Concrete Technology”, Year 2011 5) M.L.Gambhir,” Concrete Technology Theory and Prac- tice”, Year 2012 2. IS Codes 1) IS 456-2000 code of practice for plain & reinforced ce- ment concrete. 2) IS 10262-2009 recommended guide line for concrete mix design. 3) IS 9103-1999 Concrete admixture-specification. 4) IS 12269-1987 Specification for OPC 53 grades. 5) IS 383-1970 Specification for coarse aggregate and fine aggregate from natural sources. 6) IS 650-1966 Specification for standard sand for testing of cement. Author Y Raja Latha, Research Scholar, Department of Civil Engineering, Aurora’s Technological and Research Institute, Hyderabad,India. Damera Ramachander, Associate professor , Department of Civil Engineering, Aurora’s Technological and Research Institute, Hyderabad,India.