Modelling of the Microstructure and Transport Properties of Concrete.
Modelling of the Microstructure and Transport Properties
Garboczi, E. J.; Bentz, D. P.
Construction and Building Materials, Vol. 10, No. 5,
building technology; concretes; diffusivity; electrical
conductivity; interfacial zone; length scales; models;
percolation; microstructure; multi-scale
Theoretical understanding of how the properties and
performance of cement-based materials relate to
microstructure is complicated by the large range of
relevant size scales. Processes occurring in the
nanometre-sized gel pores ultimately affect the
performance of these materials at the structural level
of metres and larger. One approach to alleviating this
complication is the development of a suite of models,
consisting of individual digital-image-based structural
models for the calcium silicate hydrate gel at the
nanometre level, the hydrated cement paste at the
micrometre level, and a mortar or concrete at the
millimetre to metre level. Computations performed at
one level provide input properties to be used in
simulations of performance at the next higher level.
This methodology is demonstrated for the property of
ionic diffusivity in saturated concrete. In addition,
the ideas of percolation theory are shown to unify
microstructure and many physical phenomena at various
length scales in concrete.