Awarie Budowlane 2015
Streszczenie referatu

On September 30, 2006, part of the Boulevard de la Concorde overpass above Highway 19 in Laval (QC), Canada collapsed suddenly, resulting in serious casualties. The Government of Quebec established a public commission of inquiry (CEVC) to investigate the circumstances of the collapse, to identify its causes, and to make recommendations. The bridge design was characterized by the use of cantilever beam seats, which were at the same time vulnerable to degradation and extremely difficult to inspect. Based on the collected evidence, the collapse was due to the development and growth of a crack in a zone prone to saturation and deterioration located under the upper rebars starting from the beam seat area of the cantilevers. There was consensus among the experts as to the main physical causes of the collapse and agreement on the following points: improper rebar detailing during design; improper rebar installation at the time of construction; and, low quality concrete used for the abutments. Based on the results of the investigation, a series of 17 recommendations were issued by the CEVC.