Synthesis and microstructure analysis of autoclaved aerated concrete with carbide slag addition

Abstract

Synthesis of autoclaved aerated concrete (AAC) has been carried out with carbide slag addition, and the carbide slag could be used as a main material to produce the AAC with the compressive strength about 2 MPa and the density below 0.6 g·cm⁻³. In this study, quartz sand acted as frame structure phase in the matrix, and quartz addition also influenced the Si/Ca of starting material. Tobermorite and CSH gel were formed readily at 62%, which seemed to enhance the compressive strength of samples. Curing time seemed to affect the morphology of phase produced, and specimen with the plate-like tobermorite formed at 10 h appeared to have a better compressive strength development than the fiber-like one at 18 h. The higher curing temperature seemed to favor the tobermorite and CSH gel formation, which also exerted a significant effect on the strength development of the samples. On the micro-scale, the formed CSH gel was filled in the interface of the matrix, and the tobermorite appeared to grow in internal-surface of the pores and interstices. The tobermorite or/and CSH formation seemed to densify the matrix, and therefore enhanced the strength of the samples.

Keywords

carbide slag / autoclaved aerated concrete / tobermorite / CSH gel / construction features

References

[1] Daniel R G, Ali M M Static and Cyclic Racking Performance of Autoclaved Aerated Concrete Cladding Panels[J]. J. Archit. Eng., 2006, 12: 12-23.

[2] Ronald D N, Lawrence R Thermal Inertia Properties of Autoclaved Aerated Concrete[J]. J. Energy Eng., 1999, 125: 59-75.

[3] Robert M, Ronald D Autoclaved Aerated Concrete Produced With Low NO_x Burner/Selective Catalytic[J]. J. Energy Eng., 2001, 127: 37-50.

[4] Xiao L, Hu H Flash-ash Autoclaved Aerated Concrete and Prevention of Common[J]. Journal of Jilin Institute of Architecture & Civil Engneering, 2009, 26: 1-6.

[5] Kurama H, Topcub I B, Karakurtb C Properties of the Autoclaved Aerated Concrete Produced From Coal Bottom Ash [J]. J. Mater. Proces. Technol., 2009, 209: 767-773.

[6] Palanisamy R, Agamuthu P Carbide Sludge Management in Acetylene Producing Plants by Using Vacuum Filtration[J]. Waste Management Research, 2002, 20: 536-540.

[7] Jin H, Wu Y, Guan W Research on Producing Gas Concrete With Burnt Waste Residue[J]. Coal Technol., 2001, 20: 45-46.

[8] Ma B, Xu Z Study on a New Kind of Aerated Concrete Containing Efflorescence Sand-Phosphorus Slag-Lime[J]. J. Build. Mater., 1999, 2: 223-229.

[9] Mustafa A, Abdulkerim Y, Serdar K, . Influence of Zeolite Additive on Properties of Autoclaved Aerated Concrete[J]. Building and Environment, 2007, 42: 3 161-3 165.

[10] Cenk K Utilization of Natural Zeolite in Aerated Concrete Production[J]. Cement & Concrete Composites, 2010, 32: 1-8.

[11] Coleman N J, Trice C J, Nicholson J W 11 Å Tobermorite From Cement Bypass Dust and Waste Container Glass: A Feasibility Study[J]. Int. J. Miner. Process, 2009, 93: 73-78.

[12] Jing Z, Jin F, Yamasaki N, . Potential Utilization of Riverbed Sediments by Hydrothermal Solidification and Its Hardening Mechanism[J]. J. Environ. Manage., 2009, 90: 1 744-1 750.

[13] Jing Z, Ran X, Jin F, . Hydrothermal Solidification of Municipal Solid Waste Incineration Botom Ash With Slag Addition[J]. Waste Manage., 2010, 30: 1 521-1 527.

[14] Jing Z, Jin F, Yamasaki N, . Hydrothermal Synthesis a Novel Tobermorite-based Porous Material From Municipal Incineration Bottom Ash[J]. Ind. Eng. Chem. Res., 2007, 46: 2 657-2 660.

[15] Jing Z, Matsuoka N, Jin F, . Municipal Incineration Bottom Ash Treatment Using Hydrothermal Solidification[J]. Waste Manage., 2007, 27: 287-293.

[16] Jing Z, Ishida E H, Jin F, . Influence of Quartz Particle Size on Hydrothermal Solidification of Blast furnace Slag[J]. Ind. Eng. Chem. Res., 2006, 45: 7 470-7 474.

[17] Hemaly S A S E L, Taha A S, Didamony H E L Influence of Slag Substitution on Some Properties of Sand-lime Aerated Concrete[J]. Journal of Materials Science, 1986, 21: 1 293-1 296.

[18] Dilmore R M, Neufeld R D Autoclaved Aerated Concrete Produced with Low NO_x Burner/Selective Catalytic Reduction Fly Ash[J]. Journal of Energy Engineering-ASCE, 2001, 127(2): 37-50.

[19] Wang Q, Chen Y, Li F, . Microstructure and Properties of Silty Siliceous Crushed Stone-lime Aerated Concrete[J]. Journal of Wuhan University of Technology, 2006, 21(2): 17-20.

[20] Hartmann A, Buhl J-Ch, van Breugel K Structure and Phase Investigations on Crystallization of 11 Å Tobermorite in Lime Sand Pellets[J]. Cement and Concrete Research, 2007, 37: 21-31.

[21] Siauciunas R, Baltusnikas A Influence of SiO₂ Modification on Hydrogarnets Formation During Hydrothermal Synthesis[J]. Cement and Concrete Research, 2003, 33: 1 789-1 793.

[22] Stefano M, Elena B, Thomas A The Real Structure of Tobermorite 11 Å [J]. European Journal of Mineralogy, 2001 577-590.

[23] Jing Z, Maeda H, Loku K, . Hydrotherma Synthesis of Mesoporous Materials from Diatomaceous Earth[J]. AICHE, 2007, 53: 2 114-2 122.