This thesis discusses four issues: 1) the development of new generation of non-contact impedance measurement with frequency sweeping. 2) the hydration process monitoring of cement pastes by this measurement. 3) pore size distribution characterization of cement pastes by the non-contact impedance measurement. and 4) the development of fractal permeability model. The innovative measurement developed in this study modulates the frequency domain and measures both real and imaginary parts of the impedance with non-contact nature. An electro-chemical theory is proposed to interpret the impedance response of cement pastes. It is found that the theory can reflect the nature of the hydration of cement. The theoretical basis for pore structure characterization is the fractal electrical network, e...[ Read more ]

This thesis discusses four issues: 1) the development of new generation of non-contact impedance measurement with frequency sweeping. 2) the hydration process monitoring of cement pastes by this measurement. 3) pore size distribution characterization of cement pastes by the non-contact impedance measurement. and 4) the development of fractal permeability model. The innovative measurement developed in this study modulates the frequency domain and measures both real and imaginary parts of the impedance with non-contact nature. An electro-chemical theory is proposed to interpret the impedance response of cement pastes. It is found that the theory can reflect the nature of the hydration of cement. The theoretical basis for pore structure characterization is the fractal electrical network, electrical double layers model and frequency dispersion mechanism. The pore structures interpreted by the method have good agreement with the results obtained by other measurement such as mercury intrusion porosimetry. The fractal permeability model involves in two fractal dimensions, some structural parameters and minimal and maximal pore diameters. The validity of this permeability model is assessed by other permeability approaches (Katz-Thompson equation and water penetration test) and reasonable agreement between two methods is observed.