Transvaal park was a popular amusement park in yosenevo, south district of moscow, Russia. The park open in June 2002 and on the 14th february2004 the roof of park Collapsed Killing 28 people, including 8 children and injuring 193 people. Russian television footage from inside the park showed that beams, apparently made of concrete had collapsed onot the swimming pools. Intial reports had various theories by investigators that ” the roof at transvaal park collapsed after an explosion, but Moscow mayor and other officials later said that there was no evidence of blast”, ” the roof collapsed due to the difference between indoor and outdoor temperature”, “due to the seepage of water into the concrete supports”.
In a Dutch publication (2015) it was stated that the reason for the failure was stress corrosion cracking of stainless steel fasteners or other loaded stainless steel elements. Stress corrosion cracking(SCC) is the growth of crack formation in a corrosive environment. it can lead to unexpected sudden failure of ductile metals subjected to tensile stress especially at elvated temperature. SCC is the result of combination of three factors – a susceptible material, exposure to a corrosive environment, and tensile stresses above a threshold .
The first line of defence in controlling stress corrosion cracking is to be aware of the possibility at the design and construction stages. By choosing a material that is not susceptible to SCC in the service environment and by processing and fabricating it correctly, subsequent SCC problems can be avoided. One of the primary methods used to detect and remove materials that are susceptible to SCC is corrosion testing, there must be maintenance check on fixed intervals to evaluate the condition of the amusement park. Residual stresses can be relived by annealing or other surface treatments.
References
- https://www.nytimes.com/2004/02/15/world/21-die-in-roof-collapse-at-moscow-park.html
- https://www.rferl.org/a/1064189.html
- http://news.bbc.co.uk/2/hi/europe/3489915.stm