Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/197361

Title

Prediction of convective transport within unsaturated concrete utilizing pore size distribution data

Author(s)

Collins, Frank;  Sanjayan, Jay

Abstract

The durability of concrete structures is often compromised by physical and chemical interaction with the external environment that leads to ongoing maintenance and, in the worst cases, can lead to reduced structural integrity and consequent asset replacement. Concrete is a porous material and most field-exposed concrete is partially saturated with water. Where the concrete is unsaturated and there is no external water pressure acting on a concrete surface, the primary mechanisms of transport into concrete are convective-diffusion ingress (i.e. uptake of water and water-borne agents due to capillary attraction). This paper assesses capillarity and outlines a predictive model of the uptake of water by concrete based on analysis of the pore size distribution. It is acknowledged that concrete has a multitude of internal pores with a broad range of lengths and cross-sectional shapes, surface roughness, tortuosities, random meeting and divergence with adjacent pores, microcracks and fractures, and variable pore-water chemical composition, however the prediction model shows reasonable agreement with water sorptivity test data.

Publication type

Journal article

Source

Journal of Porous Materials, Vol. 16, no. 6 (Dec 2009), pp. 651-656

Publication year

2009

FOR Code(s)

0306 Physical Chemistry (Incl. Structural);  0912 Materials Engineering

Keyword(s)

Asset replacement;  Capillarity;  Capillary attraction;  Cement concrete;  Cements;  Chemical compositions;  Chemical interactions;  Concrete;  Concrete surface;  Convective diffusion;  Convective transport;  Cross-sectional shape;  Durability of concrete structure;  External environments;  External water pressure;  Internal pores;  Mathematical models;  Partially saturated;  Pore size;  Pore size distribution;  Pore waters;  Porous materials;  Predictive models;  Primary mechanism;  Size determination;  Size distribution;  Sorptivity;  Surface roughness;  Test data;  Unsaturated concrete;  Unsaturated flows;  Water analysis;  Water-borne;  Worst case

Publisher

Springer

ISSN

1380-2224

Publisher URL

http://dx.doi.org/10.1007/s10934-008-9245-4

Copyright

Copyright © 2008 Springer Science+Business Media, LLC.

Peer reviewed