On-line version ISSN 2309-8775
Print version ISSN 1021-2019
J. S. Afr. Inst. Civ. Eng. vol.50 n.1 Midrand Mar. 2008
H Beushausen; M G Alexander
Over the last decade, an approach to improving the durability of reinforced concrete construction has been developed in South Africa. The durability index test methods applied in this approach are unique to the country. Internationally, similar trends can be observed and a number of test methods for the quality assessment of hardened concrete, particular the cover zone have been developed world-wide. A group of researchers from different parts of the world carried out comparative tests on the quality of concrete cover, applying the most commonly accepted international test methods. The results indicate that the South African oxygen permeability and chloride conductivity test methods are successful in characterising the concrete cover in respect of important deterioration mechanisms. A good correlation exists between results obtained from these index test methods and those obtained from related test procedures applied overseas.
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Alexander, M G et al 1999-2003. Series of monographs published by University of Cape Town and the University of the Witwatersrand. [ Links ]
Alexander, M G and Beushausen, H 2007. Performance-based durability design and specification in South Africa' Proceedings International Concrete Conference and Exhibition ICCX Cape Town, January. [ Links ]
ASTM C 1202 2007. Standard Test Method for Electrical Indication of Concrete's Ability to Resist Chloride Ion Penetration. USA: ASTM. [ Links ]
Kollek, J J 1989. The determination of the permeability of concrete to oxygen by the Cembureau method - a recommendation. Materials & Structures, 22(129):225-230. [ Links ]
NTBuild 492 1999. Chloride migration coefficient from non-steady state migration experiments. Nordtest, Espoo, Finland. [ Links ]
RILEM TC116-PCD (Permeability of Concrete as a Criterion of its Durability) 1999. Recommendations, 'Determination of the capillary absorption of water of hardened concrete'. Materials and Structures, 32(4):178-179. [ Links ]
Romer, M and Fernández Luco, L 2005. RILEM TC 189-NEC, Non-destructive evaluation of the concrete cover: Comparative test - Part I: Comparative test of 'penetrability' methods. Materials & Structures, 38(284):895 - 911. [ Links ]
Swiss Standard SIA 262:2003. Concrete structures. Switzerland. [ Links ]
Torrent, R 1992. A two-chamber vacuum cell for measuring the coefficient of permeability to air of the concrete cover on site. Materials & Structures, 25(150):358-365. [ Links ]
Torrent, R and Fernández Luco, L 2007 (eds). Nondestructive evaluation of the penetrability and thickness of the concrete cover. State-of-the-art report of RILEM TC 189-NEC. Bagneux, France: RILEM. [ Links ]
Department of Civil Engineering
University of Cape Town
Mark G Alexander
Departement of Civil Engineering
University of Cape Town
HANS-DIETER BEUSHAUSEN studied structura engineering at the University of Applied Sciences in Hamburg, Germany, and the University of Cape Town (UCT), South Africa. He obtained his PhD in the Concrete Materials Research Group at UCT where he is currently employed as a senior research officer. His main research interests are durability and repair of concrete and concrete structures, and precast concrete technology.
MARK G ALEXANDER is Professor of CM Engineering in the University of Cape Town. He holds BSc(Eng), MSc(Eng) and PhD degrees from the University of the Witwatersrand. His teaching and research interests are in cement and concrete technology, with experience in materials and application to design and construction. He heads the Concrete Materials Research Group at UCT, where extensive work is being done on problems of marine concrete durability. He also acts as a specialist consultant to industry and the profession on concrete materials problems.