Geopolymer Concrete Presentation PDF

Presentation on GEOPOLYMER CONCRETE By K VENKATRAM REDDY M.E (STRUCTURAL ENGINEERING) PTPG II SEMESTER 1005-16-746121  CONTENTS ABSTRACT INTRODUCTION ABOUT GEOPOLYMER CHEMISTRY OF GEO POLYMER CONCRETE PREPERATION OF GEO POLYMER...

Presentation on GEOPOLYMER CONCRETE By K VENKATRAM REDDY M.E (STRUCTURAL ENGINEERING) PTPG II SEMESTER 1005-16-746121  CONTENTS ABSTRACT INTRODUCTION ABOUT GEOPOLYMER CHEMISTRY OF GEO POLYMER CONCRETE PREPERATION OF GEO POLYMER CONCRETE COMPARISON STUDY PROPERTIES OF GEO POLYMER CONCRETE DURABILITY AND LONG TERM STUDY OF GEO POLYMER CONCRETE MANUFACTURE OF GEO POLYMER CONCRETE APPLICATIONS OF GEO POLYMER CONCRETE ADVANTAGES OF GEO POLYMER CONCRETE DISADVANTAGES OF GEO POLYMER CONCRETE CONCLUSION  ABSTRACT The demand of concrete is increasing day by day for satisfying the need of development of infrastructure facilities. The utilization of Ordinary Portland Cement (OPC) cause hazard due to emission of CO2. To avoid this, Pozzolanic material is used as a substituted for OPC. Geo-polymer is a latest advancement in which the cement is substituted by an eco- friendly Pozzolanic material. Geopolymer is an inorganic alumino-silicate compound, synthesized from fly ash. Geopolymers are used for several applications due to their sustainability, low density, low cost, excellent thermal properties, and fire resistance.  INTRODUCTION In Ordinary cement concrete, cement act as the binder. Hydrated aluminates and silicates are responsible for this binding property. Therefore any aluminosilicate gel with properties similar to cement could be considered as an alternative for cement. Geopolymer is a class of synthetic aluminosilicate materials. This has the potential to replace Ordinary Portland cement in concrete.  ABOUT GEOPOLYMER Geopolymers are formed by alkaline activation of an alumino silicate materials like Alkali-activating solution will be prepared by mixing Sodium silicate (Na2SiO3) and Sodium hydroxide (NaOH) in the ratio 2 to 2.5 Alumino Silicate materials Low calcium Class F coal fly ash obtained from - thermal power station Blast Furnace Slag obtained from steel plant which has pozzolanic & binding properties and Metakaolin, Rice husk ash, Activated bentonite, Clay, Red mud etc. Aggregates Crushed basalt , Natural river sand Super plasticizers Bio-additives  CHEMISTRY OF GEOPOLYMER Geopolymers consist of chains or network of covalently bonded amorphous minerals with following groups of molecules. It resembles zeolites. Chemical group Name -Si-O-Si-O- siloxo, poly(siloxo) -Si-O-Al-O- sialate, poly(sialate) -Si-O-Al-O-Si-O- sialate-siloxo, poly(sialate-siloxo) -Si-O-Al-O-Si-O-Si-O- sialate-disiloxo, poly(sialate-disiloxo) -P-O-P-O- Phosphate,poly (phosphate) -P-O-Si-O-P-O Phospho-siloxo, poly(Phospho-siloxo) -P-O-Si-O-Al-O-P-O- phospho-sialate, poly(phospho-sialate) (R)-Si-O-Si-O-(R) organo-siloxo, poly-silicone PREPARATION OF GEOPOLYMER CONCRETE Constituents of geopolymer concrete Source materials:- Allumina silicate - Alkaline liquids : Combination of sodium hydroxide(Na OH) or Potassium hydroxide (KOH) and Combination of sodium silicate(Na2SiO3) or Potassium silicate (K2SiO3) Source materials rich in alumina-silicate Fly ash Metakaolin Alkaline liquid= Alkali silicates + hydroxide + distilled water Geopolymer  COMPARISON OF GPC WITH OPC Parameter Geopolymer Concrete Ordinary Portland Cement Concrete (GPC) (OPC) Production Process Alkali Activation of Wet/Dry process geopolymers (Hydration process) (Geopolymerisation) Carbon dioxide emission Low Very high Water Demand Less since geopolymers High since water activates cement activated by alkali solutions. Energy Requirement for Less energy 30% more energy than geopolymers production Micro structure of OPC Micro structure of GPC  PARAMETRIC STUDIES ON COMPRESSIVE STRENGTH OF POLYMER CONCRETE Fig. 1. Effect of alkaline liquid to fly ash ratio on Fig. 2. Effect of sodium silicate solution to sodium compressive strength hydroxide solution ratio on compressive strength Fig. 3. Effect of curing time on compressive strength Fig. 5. Effect of addition of superplasticer on compressive strength  Fig. 6. Effect of rest period on compressive strength Fig. 9. Effect of concentration of sodium hydroxide solution on compressive strength Fig. 10. Effect of curing temperature on compressive strength  PROPERTIES OF GEOPOLYMER CONCRETE Compressive Strength: Geopolymers have low early strength compared to OPC. Geopolymers have higher strength gain rate with good long term performance. Split Tensile Strength : Higher for GPC compared to OPC Modulus of Elasticity: Higher for geopolymer mixes. Thermal Resistance: Heat resistance of geopolymer materials manufactured using Class F Fly Ash, which had good thermal resistance properties up to 800°C. Corrosion Resistance: Higher for GPC Chloride Attack : Better resistance for GPC (porous alumino silicate)  DURABILITY AND LONG TERM PERFORMANCE OF GPC Suited for concrete in a sea water environment Chloride resistant concrete. Effective porosity of GPC. Optimum fly ash geopolymer has high compressive strength, tensile properties. Exposure to high Temperature Fly ash geopolymer concrete can maintain its desired compressive strength even at 400º to 500ºC. Geopolymerisation process continues even at high temperature and it is the strength of the binder or bonding that prevents the concrete from disintegration. DURABILITY AND LONG TERM PERFORMANCE OF GPC Permeability Geopolymer concretes have lower absorption rates compared to normal concrete and it decreases with increasing strength. Creep and drying Shrinkage Fly ash based geopolymers have small drying shrinkage and creep.  DURABILITY AND LONG TERM PERFORMANCE OF GPC Freeze and Thaw Mass of fly ash geopolymer concrete slightly changes after 150 freezing and defrosting cycles there was no deformation and cracking. Most efficient concrete with upto 50 % fly ash and 10% silica fume with geopolymer binder It means that excess or unreacted fly ash will not bind well with geopolymer and it will weaken the bonding only. Better resistance to Alkali Silica Reaction Geopolymer ensures prevention of alkali aggregate reaction. Fly ash also helps in controlling ASR. Use of fly ash geopolymer concrete utilizes low water-cement ratio maintaining desired workability and hence can make concrete more impermeable and less vulnerable to such reaction.  MANUFACTURE OF GEOPOLYMER CONCRETE Preparation of aggregates and fly ash by surface drying. Dry mixing of components in a pan mixer. Addition of liquid component to the dry mix. Preparation of fresh geopolymer concrete which is ready for placing. Slump test should be done for checking the workability of the concrete.  APPLICATIONS OF GEOPOLYMER CONCRETE Precast members like railway sleepers , electric poles etc… Marine Structures Pavements. Retaining walls Construction of sewer pipes.  ADVANTAGES OF GEOPOLYMER CONCRETE Eco- Friendly The price of Fly ash is very low. Better Compressive strength Fire resistance Low Permeability Excellent properties within both Acid and Salt environments  DISADVANTAGES OF GEOPOLYMER CONCRETE Geopolymerization Process is Sensitive Difficult To Create Pre mix of Geopolymers  CONCLUSIONS The reduced CO2 emissions of Geopolymers make them a good alternative to Ordinary Portland cement. With increase in the curing temperature in the range of 60 C to 90 C, the compressive 0 0 strength of the geopolymer concrete also increases. One day rest period increases the compressive strength of the geopolymer concrete as compared to that for the concrete without the rest period. Workability of the geopolymer concrete mix increases with the addition of superplasticiser up to 4% of fly ash by mass. The compressive strength of low-calcium fly ash based geopolymer concrete increased with the inclusion of OPC as fly ash replacement up to 20% at all ages. The tensile strength of geopolymer concrete increases with increase in the total aggregate content. Geopolymer concrete (GC) may possess superior fire resistance compared to conventional concretes with Ordinary Portland cement (OPC) References: 1. B. Joseph, G. Mathew / ScientiaIranica, Transactions A: Civil Engineering 19 (2012) 1188–1194 Influence of aggregate content on the behavior of fly ash based geopolymer concrete 2. A. Karthik. K. Sudalaimani, C.T. VijayakumarCeramics International 43 (2017) 11935–11943 Durability study on coal fly ash-blast furnace slag geopolymer concretes with bio-additives 3. A. Joshua Daniel, S. Sivakamasundari, A. Nishanth/ Procedia Engineering 173 ( 2017 ) 732 – 739 Study on Partial Replacement of Silica Fume Based Geopolymer Concrete Beam Behavior under Torsion 4.A. Joshua Daniela,*, S. Sivakamasundari, D. Abhilash / Procedia Engineering 173( 2017 ) 417 – 423 Comparative Study on the Behaviour of Geopolymer Concrete with Hybrid Fibers under Static Cyclic Loading 5.Prakash R. Vora and Urmil V. Dave / Procedia Engineering 51 ( 2013 ) 210 – 219 Parametric Studies on Compressive Strength of Geopolymer Concrete 6. A. Mehta, R. Siddique / Construction and Building Materials 150 (2017) 792–807 Properties of low- calcium fly ash based geopolymer concrete incorporating OPC as partial replacement of fly ash 7. A. Mehta, R. Siddique / Construction and Building Materials 146 (2017) 136–143 137 Sulfuric acid resistance of fly ash based geopolymer concrete THANK YOU