Properties of Chemically Synthesized Nano-geopolymer Cement based Self-Compacting Geopolymer Concrete (SCGC)

Abstract

The physical and mechanical properties of self-compacting geopolymer concrete (SCGC) using chemically synthesized nano-geopolymer cement was investigated. Nano-geopolymer cement was synthesized using nano-silica, alkali activator, and sodium aluminate in the laboratory. Subsequently, nine nanogeopolymer cement sbased SCGC mixes with varying nano-geopolymer cement content, alkali activator content, coarse aggregate (CA) content, and curing temperature were produced. The workability-related fresh properties were assessed through slump flow diameter and slump flow rate measurements. Mechanical performances were evaluated through compressive strength, splitting tensile strength, and modulus of elasticity measurements. In addition, rapid chloride penetration test, water absorption, and porosity tests were also performed. It was assessed that all mix design parameters influenced the fresh and hardened properties of SCGC mixes. Based on test results, it was deduced that nano-geopolymer cement SCGC performed fairly well. All the SCGC mixes achieved the 28-day compressive strength in the range of 60–80 MPa. Additionally, all mixes attained 60% of their 28-day strength during the first three days of elevated temperature curing. FTIR and SEM analyses were performed to evaluate the degree of polymerization and the microstructure respectively for SCGC mixes.

Keywords

geopolymer / compressive strength / self-compacting concrete / alkali activator / nano-silica

References

[1] Gartner EM, Macphee DE. A Physico–chemical Basis for Novel Cementitious Binders[J]. Cem. Concr. Res., 2011, 41(7): 736-749.

[2] Torgal FP, Jalali S. Eco–efficient Construction and Building Materials[ M], 2011 Berlin: Springer Science & Business Media.

[3] Singh B, Ishwarya G, Gupta M, et al. Geopolymer Concrete: A Review of Some Recent Developments[J]. Constr. Build. Mater., 2015, 85: 78-90.

[4] Xu H, Van–Deventer JSJ. The Polymerisation of Aluminio–silicate Minerals[J]. Int. J. Miner. Process., 2000, 59: 247-266.

[5] Hos J, McCormick P, Byrne L. Investigation of a Synthetic Aluminosilicate Inorganic Polymer[J]. J. Mater. Sci., 2002, 37(11): 2 311-2 316.

[6] Brew D, MacKenzie K. Geopolymer Synthesis Using Silica Fume and Sodium Aluminate[J]. J. Mater. Sci., 2007, 42(11): 3 990-3 993.

[7] O’Connor SJ, MacKenzie KJ. A New Hydroxide–based Synthesis Method for Inorganic Polymers[J]. J. Mater. Sci., 2010, 45(12): 3 284-3 288.

[8] Hajimohammadi A, Provis JL, Van Deventer JS. One–part Geopolymer Mixes from Geothermal Silica and Sodium Aluminate[J]. Ind. Eng. Chem. Res., 2008, 47(23): 9 396-9 408.

[9] Sobolev K, Gutiérrez MF. How Nanotechnology Can Change the Concrete World[J]. Amer. Ceram. Soc. Bull., 2005, 84(10): 14

[10] Sanchez F, Sobolev K. Nanotechnology in Concrete–a Review[J]. Constr. Build. Mater., 2010, 24(11): 2 060-2 071.

[11] Jo BW, Choi JS, Kang SW. An Experimental Study on Characteristics of Chemically Syntesized Nano–cement for Carbondioxide Resuction[ J]. J. Ceram. Process. Res., 2011, 12(3): 294-298.

[12] EFNARC. Guidelines for Self–compacting Concrete[S]. EFNARC–2002, 2002

[13] ASTM. Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens[S], 2002

[14] ASTM. Standard Test Method for Splitting Tensile Strength of Cylindrical Concrete Specimens[S], 2002

[15] ASTM. Standard Test Method for Static Modulus of Elasticity and Poisson’s Ratio of Concrete in Compression[S], 2002

[16] ASTM. Standard Test Method for Density, Water Absorption, and Voids in Hardened Concrete[S], 2002

[17] ASTM. Standard Test Method for Electrical Indication of Concrete Ability to Resist Chloride Ion Penetration[S], 2002

[18] Kirschner A, Harmuth A. Investigation of Geopolymer Binders with Respect to Their Application for Building Materials[J]. Ceram. Silik., 2004, 48(11): 117-120.

[19] Svingala F, Varela B. Alkali Activated Aerogels[C], 2009 In: Proceedings of the Ceramic Engineering and Science Proceedings.

[20] AbdulRahim RH, Azizli KA, Man Z, et al. Effect Sodium Hydroxide Concentration on the Mechanical Property of Non Sodium Silicate Fly Ash Based Geopolymer[J]. J. App. Sci., 2014, 14(23): 3 381-3 384.