Properties of Geopolymer concrete with two fly ashes of different sources with their varying chemical composition

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1 Properties of concrete with two fly es of different sources with their varying chemical composition Pallavi Jakate, Saurabh Asange, Avin singh Research Scholar, Dept. of Civil Engineering, Technocrat Institute of Technology (TIT) Excellence, MP, India. Assistant Professor, Dept. of Civil Engineering, Technocrat Institute of Technology (TIT) Excellence, MP, India. Assistant Professor, Dept. of Civil Engineering, Technocrat Institute of Technology (TIT) Excellence, MP, India *** Abstract Civil engineers wants to modify the properties of. Main ingredients of concrete the conventional concrete for there more satisfactory performance, so concrete is an innovative and Fly Ash- A byproduct of thermal power plant. environmental friendly construction material and an alternative soultion over portland cement concrete. Concrete GGBS- Ground Granulated Blast Furnace Slag, it is a widely used material,which requires large amout of OPC is a byproduct of steel plant. (Ordinary Portland Cement) and OPC produces large amount Fine aggregate and coarse aggregates are of carbon di oxide,which pollutes the atmosphere. Hence it is required to form the concrete mix. very important to find out the alternate solution over it. And concrete is an excellent alternative over OPC Catalytic Solution- Alkaline activator solution. because concrete can be produced with mixing any amout of OPC. Overall in GPC we can use the less/limited amount of OPC and now a days it is very much required to use environmental friendly construction material.. Materials Required Key Words: concrete, Ready Mix Concrete, Fly Ash, Strength, Ordinary Portland Cement, heat curing, ambient curing, molarity.. INTRODUCTION The name was given by French professor Mr. Davidovits in the year 978. It is very necessary to reduce the waste generation from the industries and factories, and hence cement concrete is formed by utilizing the maximum amount of wastes generated from the different sources and waste materials like fly, ground granulated blast furnace slag. Fly is the waste product generated from the thermal power plants and similarly ground granulated blast furnace slag is the waste material which is generated from the steel plant. Hence by using these waste materials in cement concrete reduces the pollution from the environment and also reduces the emission of carbon to the atmosphere. concrete is inorganic polymer composition which are formed by reaction of alkali activation of aluminosilicate waste materials which are fly Ash and GGBS. Very important part of the project is that do not forms calcium silicates hydrates to attain the structural. In this project fly plays an important role, and in this two fly es are used which are taken from the different sources with their different chemical compositions form Tamilnadu, one fly is taken from Mettur thermal power plant and another fly is taken from Tuticorin thermal power plant Tamilnadu. Oxides Fly Ash In this, Class F dry fly conforming to IS 8-00 obtained from Mettur and Tuticorin thermal power stations of Tamilnadu is used. In concrete, fly plays a very important role. Fly Ash which is going to be used should have low calcium content so that the rate of polymerization (Polymerization is a process of reacting monomer molecule to form polymer chains) should be fast. In this project work, two types of Fly es are taken with their different chemical compositions, described below in table, Mettur fly Table-: Tuticorin Fly Requirements as per IS 8-00 SiO 59.9% 6.4% SiO>5% total- >70% AlO 9.66% 7.5% SiO>5% total- >70% FeO.8%.6% SiO>5% total- >70% CaO.%.05% - NaO 0.4% 0.4% <.5% KO 0.% 0.% <.5% MgO.% 0.96% <5% LOI.56% 0.95% <% 07, IRJET Impact Factor value: 5.8 ISO 900:008 Certified Journal Page 58

2 Fine Aggregates Practically, sand is considered as fine aggregate and locally available river sand which is also termed as natural sand (Fine aggregate) having a fineness modulus of.75, specific gravity of.8 and conforming to grading zone-iii as per Indian Standards IS: was used. And the bulk density of the fine aggregate (Sand) is 69 kg/m. Coarse aggregate- Another major part of the concrete is covered by coarse aggregates. And in this locally available aggregates are being used but still aggregates should not be elongated/flaky. In this project crushed granite is used as a coarse aggregates and the maximum size of the coarse aggregate used as 9mm, in which the fineness modulus of 6.64 and a specific gravity of.7 is used. Sodium Hydroxide (NaOH) Sodium Hydroxide is an Alkali and it is a highly reactive chemical. In this NaOH is being purchased from local chemical retailer shop. Sodium Silicate In this project sodium silicate is used in the form of solution, which is manufactured at Madurai, at Salfa Industries which is again used for the preparation of alkaline activator. And the chemical composition of the sodium silicate solution by the manufacturer is as follows: 4.7% of NaO, 9.4% of SiO and 55.9% of water by mass. It is used for making the soap solution, and it was purchased from local soap chemical retailer shop. Sodium hydroxide plays an important role for the preparation of alkaline activator. Sodium hydroxide when solids, it takes the shape/ or mould itself in the form of flakes. And in this project sodium hydroxide is used is 97% pure and manufactured at Mumbai, at Merck Specialties Private Limited. Super Plasticizer This is used to achieve workability in the fresh concrete, and this is used in the form of liquid in brown color. Sulphonated naphthalene polymer based super plasticizer is used in this and Conplast SP 40 was used in all the mixtures. Conplast SP 40 is available in the form of a brown liquid that is instantly dispersible in water and is manufactured by Fosroc Chemicals (India) private limited, Bangalore. In this project Naphthalene based super plasticizer is used which is dark in color and easily available at local building material supplier. Water- Distilled water was used for the workability purpose and also for the preparation of sodium hydroxide solution. Details of mix proportion of concrete; Fly Fine aggregate Coarse aggregate Table-: NaOH solution NaSiO solution Extra water SP Importance of concrete It helps in the harmful waste reduction from the atmosphere. concrete is an alternative solution over conventional one because Conventional concrete generates tremendous amount of dust in the atmosphere. Helps in disposal of waste by utilizing fly and ground granulated blast furnace slag. Reduction in the use of cement which produces huge amount of carbon di oxide. It is an environmental (eco) friendly material. Sustainable development for better world. In this, conventional concrete is being replaced by cement concrete. GPCC have high and long life. GPCC have resistance to chloride penetration. GPCC also have resistance to chemical attack and it is capable to adjust according to the atmospheric/weather changes.. Properties of cement Concrete It has low heat of hydration as compared to conventional concrete. It provides excellent fire resisting property as compared to OPC based concrete. This concrete shows good resistance against acid attack from the atmosphere. This concrete makes good quality structural members. This concrete has less drying shrinkage. This material is now a day s widely used in pre casted members/units in construction field. Because this is actually an environmental friendly material for construction. It provides high early. There will be no chances of Alkali aggregate reaction. GPCC shows excellent performance over all its life time/ durability. 07, IRJET Impact Factor value: 5.8 ISO 900:008 Certified Journal Page 59

3 .4 Applications cement concrete is widely used today as a pre casted construction works (In which the connecting units of the building like beams, walls, columns etc are pre-casted), also used for the pavement construction, retaining walls, water tanks, pre casted bridge decks and pre casted pipes. Like this cement concrete having lots of applications in pre casted/ fabricated works.. TEST S, DISCUSSION AND RESULTS:. Slump Cone Test: Workability of freshly prepared concrete mixes was measured in terms of its slump using the conventional slump cone apparatus. All the mixtures which are made for the concrete were generally cohesive and shiny in appearance due to the presence of sodium silicate. Even though the measured slump values are more than 50mm, all the mixtures were generally stiff and the workability was poor. By testing, it has being observed that concrete prepared by using fly from Tuticorin thermal power station has better workability than the concrete prepared from Mettur fly. Workability of concrete decreases as the concentration of NaOH in the alkaline activator solution increases irrespective of the source of fly. This may be due to the reason that increasing the concentration of NaOH the total solid content in the mixture thereby reducing the water content concentration of NaOH. One fly is taken from Mettur thermal power plant and another fly is taken from Tuticorin thermal power plant. The effect of source of fly on the compressive of concrete is discussed in terms of compressive index. The compressive index is the ratio between the compressive of concrete prepared by using Mettur fly and the compressive of concrete prepared from Tuticorin fly for the same concentration of NaOH. Before subjected to the test, weight of each specimen was recorded and density of each specimen was calculated by dividing the weight of the specimen by its volume. Specimens were placed in the machine in such a manner that the load shall be applied to opposite sides of the cubes as cast, that is, not to the top and bottom of cube. Test must be conducted until the specimen breaks or crack appears on the surface of the specimen. Observations: Compressive of- GPCC with MFA Table-: Mettur fly 7 Days 8 Days Compress ive Compre ssive Cube I Cube II Cube III Cube IV Cube V Cube VI Compressive of- GPCC with TFA Table-4: Chart-: Effect of concentration of NaOH on workability. Compressive test: For the evaluation of compressive, all the cube specimens were subjected to compressive a digital compression testing machine (UTM) with a loading capacity of 000. Specimens were placed in the machine in such a manner that the load shall be applied to opposite sides of the cubes as cast, that is, not to the top and bottom. The load was applied without shock and increased continuously at a rate of approximately 4 N/mm /min until the specimen breaks down. And the maximum load is recorded. In this part, compressive is calculated by using different sources of fly es from Tamilnadu by using same Tuticorin fly 7 Days 8 Days Compress ive Compre ssive Cube I Cube II Cube III Cube IV Cube V Cube VI , IRJET Impact Factor value: 5.8 ISO 900:008 Certified Journal Page 60

4 Compressive index- Ambient curing: It has observed that the compressive of concrete prepared by using Mettur fly is higher than that of concrete prepared from Tuticorin fly in ambient curing at room temperature. Chart-4: Effect of Heat curing- Mettur fly. Chart-: Compressive index- Ambient curing Compressive index in heat curing: In heat curing, compressive indicates for most of the cases is less than one which indicates that the compressive of concrete prepared by using Tuticorin fly is greater than that of concrete prepared by using Mettur fly in heat curing Chart-: Compressive index- Heat curing Gain in Compressive : Chart-5: Effect of heat curing- Tuticorin fly.. Flexural test: Flexural of concrete was determined using prism specimens by subjecting them to two point bending in Universal Testing Machine (UTM) having a capacity of 000. The load was applied without shock and increased continuously at a rate of 800 N/min until the specimen failed. The maximum load applied to the specimen was recorded and the flexural of the specimen was calculated. The effect of various factors such as the source of fly, the concentration of NaOH solution and the curing temperature on the flexural of concrete has been investigated and presented test results of flexural are presented in Table below, Table-5: After performing the compressive test in all the cubes made up of Mettur fly and Tuticorin fly we have got the several test results, which is shown in a chart given below and chart no 5, chart no 6 showing the comparative results between GPCC made with MFA and TFA and it is observed that TFA based GPCC gives higher compressive as compared to MFA based GPCC. Gain in compressive in concrete, due to heat curing in both Mettur fly and Tuticorin fly at the same concentration of NaOH solution in show below in graph. Mettur fly 8 Days Flexural in MPa Beam I Beam II Beam III Beam IV Beam V Beam VI , IRJET Impact Factor value: 5.8 ISO 900:008 Certified Journal Page 6

5 Table-6:.4 Split test: Tuticorin fly 8 Days Flexural in MPa Beam I Beam II Beam III Beam IV Beam V Beam VI The effect of source of fly on the flexural of concrete is discussed in terms of flexural index. Flexural index is the ratio between the flexural of concrete prepared by using Mettur fly and the flexural of concrete prepared by using Tuticorin fly for the same concentration of NaOH. Flexural index Split was evaluated as per the test procedure given in Indian Standards IS.586. In order to evaluate the splitting of concrete, all the cylinder specimens were subjected to split test in a 000 kn digital compression testing machine. The load was applied without shock and increased continuously at a nominal rate within the range of. N/(mm/min) to.4 N/(mm/min) until the specimen failed or cracks forms on the surface of the cylinder. The maximum load applied to the specimen was recorded. After the tests performed on the concrete cubes following results are obtained, in this concrete is made up of Mettur fly and in this average ultimate and average split is obtained which are mentioned in the table below. Table-7: Mettur fly 7 Days 8 Days Split Split Cube I Cube II Chart-6: Flexural index in % According to our test results it has being observed that the flexural of concrete prepared by using Tuticorin fly is greater than that of concrete prepared by using Mettur fly in heat curing. Comparison between concrete made by Mettur fly and Tuticorin fly at the same concentration of NaOH is shown below in graph, at heat curing. It shows the gain in flexural. Cube III Cube IV Cube V Cube VI Tuticorin fly Table-8: 7 Days 8 Days Split Split Cube I Cube II Cube III Cube IV Cube V Cube VI Chart-7: Gain in Flexural due to heat curing. Now In this part, Split is calculated by using different sources of fly es from Tamilnadu by using same concentration of NaOH. The effect of different sources of fly on the split of 07, IRJET Impact Factor value: 5.8 ISO 900:008 Certified Journal Page 6

6 concrete is discussed in terms of split index. Chart-: Effects on heat curing- Tuticorin fly Chart-8: Split index- ambient curing From the above data (graph) it has been observed that cement concrete prepared from the Tuticorin fly gains more split at 8 days as compared to the cement concrete made up of Mettur fly at 8 days and at the same concentration of NaOH solution.. CONCLUSIONS Chart-9: Split index- heat curing Now, gain in the split of concrete made up of Mettur fly and Tuticorin fly is shown in the form of graph below, at the same concentration of NaOH with heat curing, It has been observed that from the test results, split of concrete increases as the concentration of NaOH solution increases for all the cases. Chart-0: Effects on heat curing- Mettur fly concrete prepared by using fly obtained from Tuticorin thermal power station has better workability than the concrete prepared from Mettur based fly. Workability of concrete decreases as the concentration of sodium hydroxide in the alkaline activator solution increases. The average density values of concrete ranges from 6 m to 405 which was found approximately closer to that of ordinary Portland cement concrete. Compressive of Mettur fly concrete is higher than that of Tuticorin fly based concrete in ambient curing at room temperature. Compressive of concrete increases as the concentration of NaOH solution increases. This is applicable for all the curing temperatures, age of concrete and sources of fly. Heat curing resulted in an enhancement of compressive and split at early ages only. The effect of heat curing on the increase in compressive and split is not much significant after 7 days. Rate of increase in compressive and split with respect to the age of concrete is more significant in case of ambient curing at room temperature in comparison with heat curing at 60oC Split and flexural is higher in case of Mettur fly based concrete 07, IRJET Impact Factor value: 5.8 ISO 900:008 Certified Journal Page 6

7 for the same concentration of NaOH solution and at identical curing temperature. At last it is concluded that concrete based with Tuticorin fly gives better and performance as compared to the concrete based with Mettur fly. 4. DRAWBACKS OF GEOPOLYMER CONCRETE concrete takes more time to set/ gain, as compared to the conventional concrete. Cubes made with concrete takes minimum days to set without leaving any nail impression over the cubes. This is considered as a drawback of concrete, this is observed on both the concrete cubes made of Mettur and Tuticorin fly es. To work with concrete, actually its delays the project because it takes lots of time to set which is practically not convenient. To make concrete extra ingredients are required like alkaline activator, NaOH solution etc which are not required for conventional concrete. To make concrete extra care is required for the preparation of concrete mix, and skilled labors are required. REFERENCES [] Provis JL and van Deventer JSJ (eds.), Alkali-Activated Materials: State-of-the-Art Report, Rilem TC 4-AAM. Springer/RILEM, Dordrecht, The Netherlands, 04. [] van Deventer JSJ, Provis JL, and Duxson P. Technical and Commercial Progress in the Adoption of Cement. Miner. Eng. 0; 9: [] Li C, Sun H, Li L. A review: The comparison between alkali-activated slag (Si+Ca) and metakaolin (Si+Al) cements. Cem. Concr. Res. 00; 40: [4] Duxson P, Fernández-Jiménez A, Provis JL, Lukey GC, Palomo A, van Deventer JSJ. technology: The current state of the art. J. Mater. Sci. 007; 4(9): [5] Davidovits J. Chemistry & Applications. second ed. Institut Géopolymère, Saint-Quentin, France, 009. [6] Komnitsas K, Zaharaki D. isation: a review and prospects for the minerals industry. Miner. Eng. 007; 0 (4): [7] Pacheco-Torgal F, Castro-Gomes J, Jalali S. Alkaliactivated binders: a review. Part. About materials and binders manufacture. Constr. Build. Mater. 008; (7): 5. [8] Provis JL. s and other alkali activated materials: why, how, and what? Mater. Struct. 04; 47: 5. [9] Ken PW, Ramli M, Ban CC. An overview on the influence of various factors on the properties of geopolymer concrete derived from industrial by-products. Constr. Build. Mater. 05; 77: [0] Juenger M, Winnefeld F, Provis J, Ideker J. Advances in alternative cementitious binders. Cem Concr Res 0;4:. [] Keulen A, Performance evaluation of alkali activated concrete mixtures. SQAPE, 06 [] Schweizerisches Ingenieur and Architektenverein (SIA): Determination of the resistance to sulfates of core test specimens, fast test (SIA 6/ Appendix D). Zürich, Switzerland, 00 [] Nordtest: Concrete, mortar and cement-based repair materials: Chloride migration coefficient from non-steady state migration experiments (NT BUILD 49). Espoo, Finland,999 [4] European Committee for Standardization (CEN): Products and systems for the protection and repair of concrete structures test methods Determination of resistance to carbonation (EN 95:004). Brussels, Belgium, 004 [5] Bakharev T, Sanjayan JG, Cheng YB, Sulfate attack on alkali-activated slag concrete. Cem. Concr. Res. 00, : 6. [6] Komljenovic M, Bascarevic Z, Marjanovic N, Nikolic V. External sulfate attack on alkaliactivated slag. Constr. Build. Mater. 0; 49: 9. [7] Provis JL, Palomo A, Shi, C. Advances in understanding alkali-activated materials. Cem. Concr. Res. 05, 78, 0-5. [8] Wallah S.E, Rangan BV, Low calcium fly based geopolymer concrete: long term properties. Research Report GC, Faculty of Civil Engineering, Curtin University of Technology, Perth, 006 [9] Bascarevic Z, Komljenovic M, Miladinovic Z, Nikolic V, Marjanovic N, Petrovic R. Impact of sodium sulfate solution on mechanical properties and structure of fly based geopolymers. Mater. Struct. 05; 48(): [0] Bernal SA, Provis JL, Mejia de Gutierrez R and Van Deventer JSJ, Accelerated carbonation testing of alkaliactivated slag/metakaolin blended concretes: effect of exposure conditions. Mater. Struct. 05-I; 48: [] Bernal SA, Provis JL, Carbonation testing of alkaliactivated materials what have we learned recently? Rilem meeting, Madrid 0. [] Kandasami S, Harrison TA, Jones MR, Khanna G. Benchmarking UK concretes using an accelerated carbonation test. Magazine of concrete research, Paper 008, July 0 [] Ismail I, Bernal SA, Provis JL, Nicolas RS, Brice DG, Kilcullen AR, Hamdan S, Van Deventer JSJ. Influence of fly on the water and chloride permeability of alkali-activated slag mortars and concretes. Constr. Build. Mater. 0; 48: , IRJET Impact Factor value: 5.8 ISO 900:008 Certified Journal Page 64