1. Guided by Gomathi.P AJAY.R-13BCL0051 RAJU.M-13BCL0130 GOWTHAMAN.V-13BCL0100 2. Light Weight Aggregate low density, reduced self weight of the structure, increase number of floors etc.. Geo-polymer replacement of mineral admixtures, NaOH, NaCl etc.. Introduction 3. Objectives To study the production technique of alkali-activated metakaolin aggregate. To study the various curing methods of manufactured aggregates. To analysis the physical and mechanical properties of alkali-activated based metakaolin aggregate 4. Scope: To achieve economy in concrete construction and to utilize metakaolin in an effective environment friendly manner. To meet the scarcity of cement and coarse aggregates in future To reduce the weight of the concrete by partial replacement of coarse aggregates with sintered metakaolin aggregates. To give high performance aggregate of metakaolin- silicafume. quantities of Silica Fume (SF) are added with metakaolin to compensate the deficiency occurring in initial days. 5. Types of LWC Aerated concrete No-fines concrete Lightweight aggregate concrete Natural aggregate Artificial aggregate 6. Advantages Purity of aggregate: man-made Lower dead load Better physical properties: lower modulus, lower coefficient of thermal expansion, easier drilling Improved durability: This is because of the reduced likelihood of shrinkage and early thermal cracking, lower permeability and etc. Environmental problems: The benefit can be significant of industrial waste products are used to manufacture LWA. Demolition 7. APPLICATIONS: Lightweight concrete masonry structural lightweight and semi-lightweight cast-in- place concrete Low-density precast concrete units 8. Low-density mortars for radiant heat floor and refractories. Geotechnical low-density engineered fill Concrete roofing tile and ballast Ground cover and soil-less mixes Insulating concrete fill 9. Literature survey 10. Mix proportion of LWAC ingredients studied from various literatures Author Concre te type W/b Cement content Fine aggregate content (kg/m3) VCA/V TA Light weight aggregate AE A Admixture s Ratio (kg/m3) ratio content (kg/m3) (%) (%) Natural sand Crushed sand FA-F SP 0.27 475.6 674.4 - 546.6 158.7 Yannick et al., 2006 LWAC 0.34 335.3 728.9 - 0.6 612.4 - 110.6 - 0.28 391.2 734.0 - 540 107.0 Niyazi, 2011 (Niyazi and CLWC 551 318 318 592 LWBC 0.26 548 316 317 0.6 567 0.2 - 1.1 Turan, 2011) LWGC 549 317 317 580 Wasserman and Bentur, 1997 SLWAC 0.4 440 49% 0.51 51% - - - 11. Physical characteristics of pelletized aggregates from various literatures. Authors Type of LWA used Specific gravity of LWA BD (Kg/m3) Voids (%) Water absorption (%) Crushed strength SS D OD LB D RBD LV RV 24 48 of pellet (Mpa) CLWA 1.63 1.3 789 842 39. 2 35.1 - 25.5 3.7 Niyazi and Turan, 2011 SFA+1200+10B 1.57 1.56 933 993 40. 1 36.2 - 0.7 12 SFA+1200+10G 1.6 1.59 936 936 41 37 - 0.7 9.6 Ramamurthy, 2006 SFA+20B - 1.83 850 - - 15.8 - - Amor et al., 2010 Polyurethane foam waste LWA 45 21 13. 9 - - Chi et al., 2003 CLWA 1.76 1.44 97 2 - 20. 8 8.57 12. Mechanical properties of lightweight aggregate concrete from various literatures. Author Concrete type Comp strength (Mpa) Split tensile strength (Mpa) Modulus of elasticity (Gpa) 28 d 56 d 28 d 56 d 28 d 56 d Byung-Wan et al., 2007 (Chi et al., 2003) AFLAC 26.7 - - - - - Kayali et al., 2003 (Behera, 2004) SFAC 68.0 - 6.6 - 25 - Santish and Leif, 1983 (Chao-Lung and Meng-Feng, 2005) LWAC 20.4 - - - - - SFA+1200 +10G 55.8 60.4 4.9 5.1 25.7 25.9 Niyazi and Turan, 2011 SFA+1200 +10B 53.5 59.5 4.8 5.1 26.0 26.3 LWCC 42.3 44.6 3.7 3.9 19.6 19.7 Kayali, 2008 (Grubl, 1979) FAA 66.75 - 3.75 - 25.5 - 13. Methodology: Collecting raw materials Preliminary studies Mix proportion of LWA Manufacturing process of LWA Hardening process Physical properties Mechanical properties 14. MATERIALS USED: 1. Metakaolin (NaAlSi2O6) It is a dehydroxylated form of the clay mineral kaolinite. Stones that are rich in kaolinite are known as china clay or kaolin. The particle size of metakaolin is smaller than cement particles, but not as fine as silica fume. General property: It increases strength and workability. It has higher pozzlanic activity and emits less CO2 during production. 15. 2. Silica fume : It is a byproduct of producing silicon metal or ferrosilicon alloys. One of the most beneficial uses for silica fume is in concrete and aggregates. General property: Reducing water/ cement ratio and increase strength by 100N/mm2.It improves bond strength and abrasion resistance. 16. NaOH: Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound. It is a white solid and highly caustic metallic base and alkali salt. Sodium hydroxide is soluble in water. Why ? The addition of NaOH in aggregates provides higher strength gain within shorter curing period in hot air oven. 17. Preliminary studies Specification Metakaolin Silica fume Specific gravity 2.5 2.2 % of fineness 1.0 1.0 18. Mixture proportions of various types of LWA MIX ID METAKAOLIN (%) SILICA FUME( %) NAOH MOLARITY WATER CONTENT DURATIO N CURING (AT 100C) 8MT1 80 20 8 25 15MIN OVEN 10MT1 80 20 10 25 15MIN OVEN 12MT1 80 20 12 25 15MIN OVEN 8MT2 80 20 8 28 15MIN OVEN 10MT2 80 20 10 28 15MIN OVEN 12MT2 80 20 12 28 15MIN OVEN 19. Disc Pelletizer Pelletizing is a process that involves mixing very finely ground particles of fines of size less than 200 mesh with additives and then shaping them into oval/spherical lumps of 8-16 mm in diameter by a pelletizer. It is the process of converting fines into Pellets. 20. Important parameters SPEED 55rpm ANGLE 36 SIDE DEPTH 250mm DIAMETER 500mm 21. Formation of pellets 22. Hardening process Hardening process is carried out using the hot air oven at 100c. 23. GRADATION A sieve analysis or gradation test is a practice or procedure used to assess the particle size distribution (also called gradation) of a granular material. 24. . It is expressed as the ratio of the density of the aggregate particles to the density of water. 25. Aggregates having more water absorption are more porous in nature and are generally considered unsuitable unless they are found to be acceptable based on strength, impact and hardness tests. 26. Bulk density of aggregates is the mass of aggregates required to fill the container of a unit volume after aggregates are batched based on volume. Height -30cm Diameter-15cm 27. MIX ID SPECIFIC GRAVITY WATER ABSORPTIO N(in %) BULK DENSITY (in kg/m) EFFICIENCY (in %) LBD RBD 8MT 1.31 28.3 867.47 1002.63 49.25 10MT 1.37 31.2 879.24 1017.87 51.48 12MT 1.42 26.7 921.52 1042.63 54.94 8MT 1.39 24.5 896.24 1022.21 53.42 10MT 1.46 23.8 924.56 1036.38 65.64 12MT 1.51 21.6 984.75 1063.28 68.75 PHYSICAL PROPERTIES: 28. Impact strength, is the capability of the material to withstand a suddenly applied load and is expressed in terms of energy and impact value is represented in terms of percentage . 29. The aggregate crushing value gives a relative measure of the resistance of an aggregate to crushing under a gradually applied comprehensive load. =2.8P/D 30. MECHANICAL PROPERTIES: MIX ID CRUSHING STRENGTH (7 days) in MPa IMPACT VALUE in % 8MT 12.71 17 10MT 18.45 23 12MT 24.82 32 8MT 21.98 22 10MT 26.73 37 12MT 28.42 47 31. 0 5 10 15 20 25 30 35 40 45 50 8MT1 10MT1 12MT1 8MT2 10MT2 12MT2 IMPACT VALUE IMPACT VALUE 32. 0 5 10 15 20 25 30 8MT1 10MT1 12MT1 8MT2 10MT2 12MT2 Crushing strength Crushing strength 33. Efficiency: 0 10 20 30 40 50 60 70 80 8MT1 10MT1 12MT1 8MT2 10MT2 12MT2 Molarity EFFICIENCY EFFICIENCY 34. The specific gravity of alkali activated metakaolin-silica activated aggregate with binder(25% water content) was found to have lower value as compared to metakaolin-silica aggregate with binder(28%). The lowest specific gravity 1.31 was obtained as compared to other which had specific gravity value of 1.98. Water absorption test on aggregates gives about the porosity and porosity of the aggregates decrease with increase with binder and increase in alkali activator (NaOH+water).water absorption for 25% water content reduces from 28.3% to 26.7% and water absorption for 28% water content reduces from 24.5% to 21.6%.from the above values one can interpret addition of binder and alkali activator can reduce water absorption. Addition of these effect lead to pore filling effect. Thus it can result in effective finer particles and provides an improve the micro structural strength. 35. The crushing strength and impact strength test results for various lightweight aggregates are given in the table. As larger the size and surface area compressive strength increase.12MT2has larger crushing strength of 28.42MPa and 8MT1 has lower crushing value of 12.71MPa.it is due more voids is present in 8MT1 when compared to 12MT2.Also, the impact value for lightweight aggregate consisting of 25% water content showed lower impact value compared to various binder material in aggregate(28%).the highest impact value was found out to be 47% and lowest value to be 17% . In general of all the lightweight aggregates tested the metakaolin silica activated mixes exhibited excellent mechanical properties in terms of crushing strength and impact strength. Also, the water absorption test results of metakaolin silica activated binder exhibited lowest value of 21.06 36. Work PlanJANUARY FEBRUARY MARCH APRIL MAY Lieterature review Material collection Physical properties of binder Production of aggregates Physical properties of aggregates Mechanical properties of aggregates Report submision 37. The new lightweight aggregate manufactured is suitable for use in concrete production. The important properties of the aggregate have been tested and found to be comparable to normal aggregate. The production of these aggregate is simpler potential and much cheaper than the other available production techniques. 38. Reference Bijen JMJM (1986). Manufacturing processes of artificial lightweight aggregates from fly ash. Int. J. Cement Composit. Lightweight concrete. 8(3): 191-9. Ramamurthy K, Harikrishnan KI (2006). Influence of binders on properties of sintered fly ash aggregate. Cement Concrete Composit., 28: 33-38. Niyazi Ugur Kockal, Turan Ozturan (2011). Charecteristics of lightweight fly ash aggregates produced with different binders and heat treatments. Cement Concrete Composites, 33: 61-67. Behera JP, Nayak BD, Ray HS, Sarangi B (2004). Lightweight Weight Concrete with Sintered Fly ash Aggregate: A Study on Partial Replacement to Normal Granite Aggregate. 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