The mystery of the partially collapsed Izbor viaduct

On Saturday, 6 May 2006, the launching of the deck superstructure of the Izbor viaduct resulted in the partial collapse of the front section of the launched deck. The construction process of launching the deck was aided by a tower and supporting cable-stayed system. This paper describes the investigation, including on-site material inspections and in-depth analysis, which was carried out to determine the likely cause of the partial collapse. The design and construction deficiencies, which were identified during the assessment of the viaduct, allowed an understanding of the anatomy of the partial failure. Following the investigation, the mystery of the Izbor viaduct was revealed.