Comparison of long term performance between alkali activated slag and fly ash geopolymer concretes

Abstract This paper reports the comparison of engineering properties of alkali activated slag (AAS) and low calcium fly ash geopolymer (FAGP) concretes up to 540 days. The results showed that the AAS concrete had higher compressive and tensile strength, elastic modulus and lower permeation characteristics than FAGP concrete in the initial 90 days. However, a reduction in AAS concrete performance was observed between 90 and 540 days, while an increase was noted in FAGP concrete over the same time period. The microscopy revealed that both reactions progressed beyond 90 days with the slag–alkali producing excess C–S–H gel which was observed to increase the crack propagation and crack width at latter ages, attributed to the combined effect of disjoining pressure and self-desiccation. The fly ash geopolymerization also continued following an initial 24 h heat curing resulting in a crack-free dense microstructure at 540 days. Overall the discrepancy in microstructural development beyond 90 days in the two concretes would explain the contradictory performance over the longer time frame.

[1]  J. Sanjayan,et al.  Microcracking and strength development of alkali activated slag concrete , 2001 .

[2]  X. Querol,et al.  Environmental, physical and structural characterisation of geopolymer matrixes synthesised from coal (co-)combustion fly ashes. , 2008, Journal of hazardous materials.

[3]  R. Shrestha,et al.  Mechanical Properties of Geopolymer Concrete: Applicability of Relationships Defined by AS 3600 , 2013 .

[4]  Jouni Punkki,et al.  Effects of curing: comparison of optimised alkali-activated PC-FA-BFS and PC concretes , 2014 .

[5]  E. Allouche,et al.  Factors affecting the suitability of fly ash as source material for geopolymers , 2010 .

[6]  A. Neville.  Properties of Concrete , 1968 .

[7]  F. R. Montgomery,et al.  ‘CLAM’ tests for measuring in-situ permeation properties of concrete , 1995 .

[8]  J. Davidovits.  High-Alkali Cements for 21st Century Concretes , 1994, "SP-144: Concrete Technology: Past, Present, and Future".

[9]  A. Boyle,et al.  Factors influencing the compressive strength of fly ash based geopolymers , 2016 .

[10]  D. Huntzinger,et al.  A life-cycle assessment of Portland cement manufacturing: comparing the traditional process with alternative technologies , 2009 .

[11]  Bhupinder Singh,et al.  Geopolymer concrete: A review of some recent developments , 2015 .

[12]  Kyung-Taek Koh,et al.  The mechanical properties of fly ash-based geopolymer concrete with alkaline activators , 2013 .

[13]  Waltraud M. Kriven,et al.  The effect of alkali and Si/Al ratio on the development of mechanical properties of metakaolin-based geopolymers , 2007 .

[14]  Andrzej Garbacz,et al.  Ultrasonic Evaluation Methods Applicable to Polymer Concrete Composites. | NIST , 2003 .

[15]  N. Roussel,et al.  An environmental evaluation of geopolymer based concrete production: reviewing current research trends , 2011 .

[16]  C. Meyer.  The greening of the concrete industry , 2009 .

[17]  Frank Rendell,et al.  Deteriorated Concrete: Inspection and Physicochemical Analysis , 2002 .

[18]  Ali Nazari,et al.  Distribution of oxides in fly ash controls strength evolution of geopolymers , 2014 .

[19]  Ángel Palomo,et al.  Engineering Properties of Alkali-Activated Fly Ash Concrete , 2006 .

[20]  John L. Provis,et al.  Engineering and durability properties of concretes based on alkali-activated granulated blast furnac , 2012 .

[21]  Mohd Zamin Jumaat,et al.  Enhancement of mechanical properties in polypropylene– and nylon–fibre reinforced oil palm shell concrete , 2013 .

[22]  Erez N. Allouche,et al.  Mechanical Properties of Fly-Ash-Based Geopolymer Concrete , 2011 .

[23]  Aaron R. Sakulich,et al.  Mechanical and microstructural characterization of an alkali-activated slag/limestone fine aggregate concrete , 2009 .

[24]  Wichian Chalee,et al.  Effect of sodium hydroxide concentration on chloride penetration and steel corrosion of fly ash-based geopolymer concrete under marine site , 2014 .

[25]  B. Rangan,et al.  DEVELOPMENT AND PROPERTIES OF LOW-CALCIUM FLY ASH-BASED GEOPOLYMER CONCRETE , 2005 .

[26]  K. Sagoe-Crentsil,et al.  Relationships between composition, structure and strength of inorganic polymers , 2005 .

[27]  Andi Arham Adam,et al.  Strength and durability properties of alkali activated slag and fly ash-based geopolymer concrete , 2009 .

[28]  G. Corder,et al.  Costs and carbon emissions for geopolymer pastes in comparison to ordinary portland cement , 2011 .

[29]  C. Chen,et al.  Environmental impact of cement production: detail of the different processes and cement plant variability evaluation , 2010 .

[30]  Prinya Chindaprasirt,et al.  Controlling ettringite formation in FBC fly ash geopolymer concrete , 2013 .

[31]  J. Provis.  Geopolymers and other alkali activated materials: why, how, and what? , 2014 .

[32]  K. Sagoe-Crentsil,et al.  Dissolution processes, hydrolysis and condensation reactions during geopolymer synthesis: Part I—Low Si/Al ratio systems , 2007 .

[33]  Ángel Palomo,et al.  Alkali-activated fly ashes: A cement for the future , 1999 .

[34]  William D.A. Rickard,et al.  In-situ thermo-mechanical testing of fly ash geopolymer concretes made with quartz and expanded clay aggregates , 2016 .

[35]  Xian Zheng Gong,et al.  CO2 Emissions due to Cement Manufacture , 2011 .

[36]  T. Bakharev,et al.  Geopolymeric materials prepared using Class F fly ash and elevated temperature curing , 2005 .

[37]  Erich D. Rodríguez,et al.  Effect of binder content on the performance of alkali-activated slag concretes , 2011 .

[38]  Ali Akbar Ramezanianpour,et al.  Engineering Properties of Alkali-Activated Natural Pozzolan Concrete , 2011 .

[39]  Pan Chen,et al.  Modeling of Carbon Dioxide Measurement on Cement Plants , 2012 .

[40]  H. Nikraz,et al.  Water Penetrability of Low Calcium Fly Ash Geopolymer Concrete , 2008 .

[41]  Frank Collins,et al.  Effect of pore size distribution on drying shrinkage of alkali-activated slag concrete , 2000 .

[42]  Sujeeva Setunge,et al.  Zeta potential, gel formation and compressive strength of low calcium fly ash geopolymers , 2015 .