Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/193023

Title

Evaluation of coatings, mortars and mix design for protection of concrete against sulphur oxidising bacteria

Author(s)

Berndt, M. L.

Abstract

Deterioration of concrete in cooling tower basins by microbiologically influenced corrosion (MIC) is a concern in geothermal power plants. The effect of supplementary cementitious materials, epoxy coatings, latex-modified mortars and calcium aluminate cement mortar for protecting concrete from MIC was investigated. Laboratory exposure tests to a particular type of sulphur and iron oxidising bacteria, Thiobacillus ferrooxidans, were performed to rank candidate materials and these were followed by field exposure tests of the best materials in a cooling tower basin. It was determined that partial replacement of cement with 40% blast furnace slag or 5% to 10% silica fume improved resistance to MIC. A replacement level of 60% slag resulted in similar performance to concrete made with ordinary Portland or sulphate resistant cement. Epoxy- and styrene butadiene latex-modified mortars offered protection to concrete but still underwent a degree of attack. Epoxy coatings were found to be effective in protecting concrete. Calcium aluminate cement mortar showed excellent durability in laboratory and field tests.

Publication type

Journal article

Research centre

Swinburne University of Technology. Faculty of Engineering and Industrial Sciences. Centre for Sustainable Infrastructure

Source

Construction and Building Materials, Vol. 25, no. 10 (Oct 2011), pp. 3893-3902

Publication year

2011

FOR Code(s)

0905 Civil Engineering;  1202 Building

Keyword(s)

Blast furnace slag;  Calcium aluminate cement;  Durability;  Epoxy coatings;  Microbiologically influenced corrosion;  Silica fume

Publisher

Elsevier

ISSN

0950-0618

Publisher URL

http://dx.doi.org/10.1016/j.conbuildmat.2011.04.014

Copyright

Copyright © 2011 Elsevier Ltd. All rights reserved.

Peer reviewed