Recent Developments in the Measurement of Transport Properties in Cement-Based Materials.
Recent Developments in the Measurement of Transport
Properties in Cement-Based Materials.
Shane, J. D.; Hwang, J. H.; Sohn, D.; Mason, T. O.;
Jennings, H. M.; Garboczi, E. J.
Mechanisms of Chemical Degradation of Cement-Based
Systems. Proceedings of the Materials Research Society's
Symposium on Mechanisms of Chemical Degradation of
Cement-Based Systems. November 27-30, 1995, Boston, MA,
E & FN Spon, London, England, Scrivener, K. L.; Young,
J. F., Editor(s)(s), 413-423 pp, 1997.
diffusivity; impedance spectroscopy; mercury intrusion
porosimetry; modeling; nuclear magnetic resonance;
permeability; solvent exchange; transport properties
Fundamental to understanding and controlling the
durability of cement-based systems is the relationship
between microstructure and transport properties,
particularly ionic diffusivity and hydraulic
permeability. While our understanding of cement paste
microstructure and interfacial zone contributions has
improved considerably over the past few years, largely
due to advances in nondestructive methods and modelling,
there is a demonstrated need for improved laboratory and
field techniques for determining diffusivity and
permeability. This work provides an overview of
existing and emerging techniques for measuring or
predicting the transport properties of cement-based
materials. Although a major focus will be impedance
spectroscopy, alternative methods will also be
considered, including solvent exchange kinetics, mercury
intrusion proosimetry, nuclear magnetic resonance,
microstructure-based modelling, and the more
conventional permeameter and rapid chloride penetration
techniques. The applicability of the Nernst-Einstein
(diffusivity) and Katz-Thompson (permeability) equations
to cement-based materials will be considered.
Ramifications for rapid testing and field testing of
concrete will also be discussed.