Experiment research on mix design and early mechanical performance of alkali-activated slag using response surface methodology (RSM)

Abstract To enhance the quality of alkali-activated slag (AAS) materials, scientific and efficient mix design method is preferred. This paper presents an optimization of AAS materials using Response Surface Methodology (RSM). Three factors related to early strength such as modulus ( n ), concentration of alkali activator (CAA) and liquid–solid ratio (LSR) were investigated. Specimens with different mix ratios were prepared based on RSM design. The early mechanical performance was assessed, after 2 or 3 h of curing. Then response surface models were established and the effect law of each factor was systemically analyzed. The result shows that both n and CAA have a significant effect on the early strength, while LSR affects slightly. By adjusting the mix design parameters, the early performance of AAS can be effectively improved. This study verifies that RSM is efficient in the preparation of AAS and it can control the early strength of AAS accurately.

[1]  Cengiz Duran Atiş,et al.  Influence of Activator on the Strength and Drying Shrinkage of Alkali-Activated Slag Mortar , 2009 .

[2]  Jinyu Xu,et al.  Systematic study on the basic characteristics of alkali-activated slag-fly ash cementitious material system , 2012 .

[3]  B. Vijaya Rangan,et al.  ON THE DEVELOPMENT OF FLY ASH-BASED GEOPOLYMER CONCRETE , 2004 .

[4]  C. Shi,et al.  Early strength development and hydration of alkali-activated blast furnace slag/fly ash blends , 1999 .

[5]  Jinyu Xu,et al.  Static and dynamic mechanical properties of high early strength alkali activated slag concrete , 2015 .

[6]  Zhang Yunsheng,et al.  Synthesis and heavy metal immobilization behaviors of slag based geopolymer. , 2007, Journal of hazardous materials.

[7]  M. Murmu,et al.  Hydration Products, Morphology and Microstructure of Activated Slag Cement , 2014, International Journal of Concrete Structures and Materials.

[8]  Stefania Manzi,et al.  Mix-design and characterization of alkali activated materials based on metakaolin and ladle slag , 2013 .

[9]  J. Davidovits.  Geopolymers : inorganic polymeric new materials , 1991 .

[10]  Yao Xiao,et al.  Role of water in the synthesis of calcined kaolin-based geopolymer , 2009 .

[11]  W. Yong-gen.  Manufacturing Process and Properties of Alkali-Slag Mineral Polymer Concrete , 2010 .

[12]  Susan A. Bernal,et al.  Performance of an alkali-activated slag concrete reinforced with steel fibers , 2010 .

[13]  R. H. Atkinson.  Recent advances in the applied chemistry of the rare metals. Jubilee memorial lecture , 1940 .

[14]  Hamlin M. Jennings,et al.  Density and water content of nanoscale solid C–S–H formed in alkali-activated slag (AAS) paste and implications for chemical shrinkage , 2012 .

[15]  Aaron R. Sakulich,et al.  Mitigation of autogenous shrinkage in alkali activated slag mortars by internal curing , 2013 .

[16]  Jay G. Sanjayan,et al.  Cracking tendency of alkali-activated slag concrete subjected to restrained shrinkage , 2000 .

[17]  P. L. Pratt,et al.  Factors affecting the strength of alkali-activated slag , 1994 .

[18]  Fernando Pacheco-Torgal,et al.  Alkali-activated binders: A review: Part 1. Historical background, terminology, reaction mechanisms and hydration products , 2008 .

[19]  K. Scrivener,et al.  Hydration products of alkali activated slag cement , 1995 .

[20]  Francisca Puertas,et al.  Effect of Shrinkage-reducing Admixtures on the Properties of Alkali-activated Slag Mortars and Pastes , 2007 .

[21]  Wang Guo-Cai,et al.  Study of Early Strength and Shrinkage Properties of Cement or Lime Solidified Soil , 2012 .

[22]  V. M. Malhotra,et al.  Properties and Durability of Alkali-Activated Slag Concrete , 1992 .

[23]  J. Davidovits.  Geopolymers and geopolymeric materials , 1989 .