Measuring structural (un)safety in the Dutch building industry

The last 10 years the Dutch Building Industry was shocked by several major accidents. In 2001 the steel structure of a theatre in Hoorn collapsed during erection. No one was hurt, because it collapsed during the night. In 2002 part of the parking deck of a hotel collapsed just some time after a conference beneath was finished. In 2003 5 balconies of a resident building in Maastricht broke down, 2 persons were killed[1]. Besides several buildings showed major cracks in concrete elements and were evacuated, like the bos & lommercomplex in Amsterdam (2006). The mentioned accidents received much media attention. The question arose whether these events were just incidents or indicators of a system problem in the building industry. Besides, questions on causes and measures to reduce the risks arose. A committee: “Learning from disasters” was started in 2004 with several members from building industry, government and universities. It appeared that there had been no systematic collection of failure data unlike in some other countries. In these days TNO started a database with reported accidents and TUDelft joined this initiative in 2009 to get insight in the amount and causes of structural failures. For the database TNO and TUDelft were looking for that cases from 1993-2008 with -an unacceptable probability of structural failure of the building or of a structural member of a building -a situation endangering people -a building less than 50 years of age -a building with loadings according to Dutch Building Code A broad definition of buildings is applied, so information on bridges, dams, temporary structures and buildings were all included. The goal of this paper is to explain how to set up and analyse a database on structural failures.