Three types of pure geopolymer pastes (poly-sialate PS, poly- sialate-siloxo PSS, and poly-sialate-siloxo PSDS) werefi rst prepared by alkali (NaOH and KOH) activated metakaolin. Then a void space network was employed to simulate the 3-D pore-throat distribution across the unit cell of the various hardened geopolymer pastes with reference to their experimental mercury intrusion curves. Based on the simulated 3-D pore-throat structure models, a wide range of pore-level properties such as porosity, connectivity, permeability and tortuosity of various geopolymer pastes were calculated. The 3-D structural model and calculated parameters showed that most of the pores in Na-PS geopolymer paste was very small size pores ranging from 0 to 100 nm. A few very large pores were spread amongst the small pores, resulting in a very high penetration pressure, permeability resistance. Unlike Na-PS geopolymer paste, pore size with medium size of Na-PSS, K-PS and K-PSS geopolymer pastes distributed uniformly across the unit cell, and the size changes of adjacent pores in the 3 geopolymer pastes were little, producing higher penetration pressure, lower permeability, smaller connectivity and larger tortuosity. In contrast, pores in Na-PSDS and K-PSDS geopolymer pastes were relatively large and distributed concentratively, which caused samples to be easily penetrated by mercury, methane and nitrogenetc under relatively low pressures.
参考文献
| [1] | Kinrade SD.;Pole DL.;Syvitski RT.;Knight CTG. .Silicon-29 NMR studies of tetraalkylammonium silicate solutions. 1. Equilibria, Si-29 chemical shifts, and Si-29 relaxation[J].Inorganic Chemistry: A Research Journal that Includes Bioinorganic, Catalytic, Organometallic, Solid-State, and Synthetic Chemistry and Reaction Dynamics,1998(17):4272-4277. |
| [2] | Santiago Alonso;Angel Palomo .Calorimetric study of alkaline activation of calcium hydroxide-metakaolin solid mixtures[J].Cement and Concrete Research,2001(1):25-30. |
| [3] | Jaarsveld V.N.;Lorenzen L. .THE POTENTIAL USE OF GEOPOLYMERIC MATERIALS TO IMMOBILISE TOXIC METALS: PART I. THEORY AND APPLICATIONS[J].Minerals Engineering,1997(7):659-669. |
| [4] | A.Palomo;M.T.B.Varela .Chemical stability of cementitious materials based on metakaolin[J].Cement and Concrete Research,1999(6):997-1004. |
| [5] | Zhang YS;Sun W;Li ZJ .Preparation and microstructure of K-PSDS geopolymeric binder[J].Colloids and Surfaces, A. Physicochemical and Engineering Aspects,2007(1/3):473-482. |
| [6] | G. Peter Matthews;Adam K. Moss;Cathy J. Ridgway .The effects of correlated networks on mercury intrusion simulations and permeabilities of sandstone and other porous media[J].Powder Technology,1995(1):61-77. |
| [7] | ZHANG YUNSHENG SUN WEI .PREPARATION AND MICROSTRUCTURE OF Na-PSDS GEOPOLYMERIC MATRIX[J].Cearmics: Silikaty,2009(2):88-97. |
| [8] | Zhang Yunsheng;Sun Wei;Li Zongjin .Synthesis and Microstructural Characterization of Fully?Reacted Potassium-Poly (sialate-Siloxo) Geopolymeric Cement Matrix[J].ACI materials journal,2008(2):156-164. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%