Impedance Spectroscopy of Hydrating Cement‐Based Materials: Measurement, Interpretation, and Application

This work concerns the state of the art for use of impedance spectroscopy for studying the evolving microstructure of cement-based materials during hydration. Features of the spectra are discussed and related to components of the microstructure with the assistance of pixel-based computer modeling techniques. It is proposed that the enormously high relative dielectric constants (∼105) observed just after set are the result of dielectric amplification and are related to the distribution of pore sizes and the thickness of product C─S─H layers separating the pores. The conductivity is related to the volume fraction of porosity, the conductivity of the pore solution, and the interconnectivity of the porosity. The conductivity, when normalized by that of the pore solution, i.e., inverse formation factor, is a measure of this interconnectivity and can be used to predict such engineering properties as ionic diffusivity and water permeability. Composite mixing laws are employed to aid in explaining the behavior of the conductivity and to obtain a qualitative measure of the pore shape with hydration. Procedures for predicting the conductivity of the pore solution and for subtracting out electrode lead effects at high frequency are discussed.

[1]  E. Bonatti,et al.  Peridotites from the Island of Zabargad (St. John), Red Sea: Petrology and geochemistry , 1986 .

[2]  J. Beaudoin,et al.  Application of A.C. impedance techniques in studies of porous cementitious materials , 1993 .

[3]  Thompson,et al.  Quantitative prediction of permeability in porous rock. , 1986, Physical review. B, Condensed matter.

[4]  J. Beaudoin,et al.  A.C. impedance spectroscopy (I): A new equivalent circuit model for hydrated portland cement paste , 1992 .

[5]  H. W. Whittington,et al.  The conduction of electricity through concrete , 1981 .

[6]  W. McCarter,et al.  Dependence of electrical impedance of cement-based materials on their moisture condition , 1989 .

[7]  K. Byfors,et al.  Influence of silica fume and flyash on chloride diffusion and pH values in cement paste , 1987 .

[8]  J. Beaudoin,et al.  An a.c. impedance spectroscopy study of micro-cracking in cement-based composites during compressive loading , 1993 .

[9]  G. Niklasson,et al.  CIRCUIT MODELS FOR CEMENT BASED MATERIALS OBTAINED FROM IMPEDANCE SPECTROSCOPY , 1991 .

[10]  F. Tamás.  Electrical conductivity of cement pastes , 1982 .

[11]  Thomas O. Mason,et al.  Influence of Silica Fume on the Early Hydration of Portland Cements Using Impedance Spectroscopy , 1992 .

[12]  William John McCarter,et al.  The A.C. response of hardened cement paste , 1990 .

[13]  E. Hekal,et al.  Electrical conductivity of cement pastes in different curing media , 1989 .

[14]  J. Beaudoin,et al.  Flat aggregate-portland cement paste interfaces, I. Electrical conductivity models , 1991 .

[15]  B. Allard,et al.  Chemical composition of cement pore solutions , 1989 .

[16]  W. Hansen,et al.  Effect of first drying upon the pore structure of hydrated alite paste , 1980 .

[17]  W. Nix,et al.  Dislocations in extruded Co-49.3at% Al , 1986 .

[18]  Computer Simulation of Impedance Spectroscopy in Two Dimensions: Application to Cement Paste , 1993 .

[19]  J. Larbi,et al.  The chemistry of the pore fluid of silica fume-blended cement systems , 1990 .

[20]  P. Camp,et al.  Dielectric properties of portland cement paste as a function of time since mixing , 1989 .

[21]  Kenneth J. Olp,et al.  Electromagnetic properties of mortars over a broad frequency range and different curing times , 1991 .

[22]  Charles W. Tobias,et al.  On the Conductivity of Dispersions , 1959 .

[23]  D. Williams,et al.  An a.c. impedance study of steel in concrete , 1985 .

[24]  A. Katz,et al.  Prediction of rock electrical conductivity from mercury injection measurements , 1987 .

[25]  Experimental and Computer Simulation Results for the Electrical Conductivity of Portland Cement Paste , 1991 .

[26]  Dependence of the electrical resistivity on evaporable water content in hardened cement pastes , 1987 .

[27]  K. Arulanandan,et al.  RELATIONSHIPS BETWEEN ELECTRICAL AND PHYSICAL PROPERTIES OF CEMENT PASTES , 1974 .

[28]  H. Taylor.  A method for predicting alkazi ion concentrations in cement pore solutions , 1987 .

[29]  C. L. Page,et al.  Diffusion of chloride ions in hardened cement pastes , 1981 .

[30]  G. E. Archie.  The electrical resistivity log as an aid in determining some reservoir characteristics , 1942 .

[31]  Edward J. Garboczi,et al.  Permeability, diffusivity, and microstructural parameters: A critical review , 1990 .

[32]  William John McCarter,et al.  ELECTRICAL-RESISTIVITY CHARACTERISTICS OF AIR-ENTRAINED CONCRETE , 1983 .

[33]  W. McCarter,et al.  Impedance measurements on cement paste , 1988 .

[34]  S. Shtrikman,et al.  A Variational Approach to the Theory of the Effective Magnetic Permeability of Multiphase Materials , 1962 .

[35]  H. Jennings,et al.  Impedance spectra of hydrating cement pastes , 1991 .

[36]  E. Garboczi,et al.  Computer simulation of the diffusivity of cement-based materials , 1992 .

[37]  J. Beaudoin,et al.  Application of A.C. impedance techniques in studies of porous cementitious materials (III): ACIS behavior of very low porosity cementitious systems , 1993 .

[38]  E. Garboczi,et al.  Simulation Studies of the Effects of Mineral Admixtures on the Cement Paste-Aggregate Interfacial Zone (SP-105) , 1991 .

[39]  S. Kirkpatrick.  Percolation and Conduction , 1973 .

[40]  P. Aitcin,et al.  The effect of drying on cement pastes pore structure as determined by mercury porosimetry , 1988 .

[41]  J. Beaudoin,et al.  Impedance characterization of microcracking behaviour in fibre-reinforced cement composites , 1993 .

[42]  Interpretation of impedance spectroscopy of cement paste via computer modelling , 1995, Journal of Materials Science.

[43]  R. Newnham,et al.  Electrical Resistivity of Composites , 1990 .

[44]  G. Niklasson,et al.  Dielectric properties of porous cement mortar: Fractal surface effects , 1991 .

[45]  A. K. Nickerson,et al.  The diffusion of ions through water-saturated cement , 1984 .

[46]  E. R. Atkins,et al.  The Significance of Particle Shape in Formation Resistivity Factor-Porosity Relationships , 1961 .

[47]  Edward J. Garboczi,et al.  Percolation of phases in a three-dimensional cement paste microstructural model , 1991 .

[48]  J. Beaudoin,et al.  APPLICATION OF A.C. IMPEDANCE TECHNIQUES IN STUDIES OF POROUS CEMENTITIOUS MATERIALS (II): RELATIONSHIP BETWEEN ACIS BEHAVIOR AND THE POROUS MICROSTRUCTURE , 1993 .

[49]  D. Roy,et al.  Low-frequency electrical conductivity of cement, clinker and clinker mineral pastes , 1987 .

[50]  J. Beaudoin,et al.  A rationalized a.c. impedence model for microstructural characterization of hydrating cement systems , 1993 .

[51]  Sidney Diamond,et al.  Expression and analysis of pore fluids from hardened cement pastes and mortars , 1981 .

[52]  James J. Beaudoin,et al.  A.C. impedance spectroscopy (II): Microstructural characterization of hydrating cement-silica fume systems , 1993 .

[53]  Some aspects of the electrical properties of cement paste , 1984 .

[54]  J. Beaudoin,et al.  Microstructural characterization of the transition zone in cement systems by means of A.C. impedance spectroscopy , 1993 .

[55]  Dirch H. Bager,et al.  Ice formation in hardened cement paste, Part I — room temperature cured pastes with variable moisture contents , 1986 .

[56]  Lars-Olof Nilsson,et al.  Dielectric properties of cement mortar as a function of water content , 1992 .

[57]  D. Roy,et al.  Influence of chemical composition and inorganic admixtures on the electrical conductivity of hydrating cement pastes , 1989 .

[58]  B. K. Nyame,et al.  Relationships between permeability and pore structure of hardened cement paste , 1981 .