Concrete cancer
From Wikipedia, the free encyclopedia
A euphemistic name for a failure mode of concrete. If the cement component is too alkaline, it reacts with atmospheric carbon dioxide, and the structure will begin to deteriorate as star-shaped cracks appear which allow rainwater to penetrate. This deterioration is then accelerated by freeze-thawing of water in the cracks, which causes the surface to spall (erode and fall away).[1]
Contents |
[edit] Treatment
Concrete cancer can be treated in some structures[2]. In order to effect repairs, the spalled concrete must be removed and any exposed steel must either be replaced or cleaned and treated. The area is then repaired to the original concrete profile using cement mortar, epoxy mortar or concrete, depending on the size of the damage and the structural requirements. Cracks are repaired using suitable epoxy resins, special mortars and injection techniques [3].
[edit] Incidence
The BBC quoted Professor Andrew Beeby, University of Leeds civil engineering lecturer and a member of the Magazine of Concrete Research's editorial panel, as saying:
"Concrete cancer has enjoyed a lot of media coverage and prompted a huge amount of research. It is very rare and tends to make a structure look nasty rather than render it unsafe." [4]
[edit] Structures said to be affected
- Millennium Stadium, Wales – North Stand (Part of the old National Stadium) [5];
- Pebble Mill Studios, Birmingham, England
- ATV building, Birmingham, England
- Express Lift Tower, Northampton, England
- Centennial Hall, Adelaide, Australia (demolished in 2007)
- King St Bridge (crossing the Patawalonga River, Glenelg North, South Australia) [6]
- The Kingsway Centre, Newport, South Wales
- Several raised portions of the M6 in Birmingham, England
- circa 1920s housing in Horfield, Bristol, England
[edit] References
- ^ BBC h2g2 Encyclopaedia Project – Concrete Cancer entry [1]
- ^ ”Our House” TV program – Nine Network - Fact Sheet (NineMSN)[2]
- ^ BBC h2g2 Encyclopaedia Project ibid [3]
- ^ BBC News “In defence of concrete”, 13 January 2001; [ http://news.bbc.co.uk/2/hi/uk_news/1114063.stm]
- ^ Laura Kemp, Wales on Sunday, “THE Millennium Stadium is suffering from concrete cancer, we can reveal”, 8 July 2007; [4]
- ^ Anna Vlach, The Adelaide Advertiser, “Pat bridge load fears”, 8 August 2007, page 9
