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Statistische Auswertungen von Brückeneinsturzdaten zeigen, dass Massivbrücken signifikant seltener einstürzen als Brücken aus Stahl oder Holz. Da weltweit die Hauptursache für Brückeneinstürze Hochwasser und damit verbundene fluviale Prozesse wie Auskolkung, Muren etc. und Anpralle sind, liegt die Vermutung nahe, dass die hohe Eigenlast der Massivbrücken zu einem insgesamt robusteren Verhalten bei diesen Ereignissen führt. Im Rahmen dieses Beitrags soll geprüft werden, ob die IABSE-Einsturzdatenbank diese These bestätigt und Hinweise auf weitere Ursachen identifiziert werden können. Dazu wird die IABSE-Einsturzdatenbank mittels Verfahren der Künstlichen Intelligenz und des maschinellen Lernens (KI/ML) untersucht. Die KI/ML-Analyse bestätigt die bisherige These allerdings nicht. Im Weiteren werden Ursachen für die Ablehnung der These, wie z.B. die Repräsentativität der Daten, diskutiert. Es wird eine Erweiterung der Datenbank für Ereignisse mit großen Einsturzzahlen empfohlen., Statistical analyses of bridge collapse data show that concrete bridges collapse significantly less frequently than bridges made of steel or wood. Since the main causes of bridge collapses worldwide are floods and associated fluvial processes, such as scouring, debris flows, etc. and impacts, it is reasonable to assume that the high dead load of concrete bridges leads to an overall more robust behavior in these events. This paper will examine whether the IABSE collapse database confirms this hypothesis and whether indications of further causes can be identified. For this purpose, the IABSE collapse database is examined using artificial intelligence and machine learning (AI/ML) methods. However, the AI/ML analysis does not confirm the previous thesis. The reasons for the rejection of the thesis, such as the representativeness of the data, are also discussed. An extension of the database for events with large numbers of collapses is recommended.

U radu je dan pregled forenzičkog inženjerstva u građevinarstvu, strategije koja slijedi nakon otkazivanja mostova. Provedena je statistička analiza i sistematizacija raspoloživih podataka o otkazivanjima mostova u cijelom svijetu u vremenskom razdoblju od 1966.- 2020. godine. Detaljno je analizirano više od 600 slučajeva djelomičnog ili potpunog rušenja mostova te su analizirani uzroci koji su doveli do njihovog otkazivanja. Do otkazivanja svakog od ovih mostova najčešće nije došlo uslijed samo jednog faktora, već je glavni uzrok je najčešće okidač u uzročnoposljedičnom slijedu niza događaja koji su tome pridonijeli. Sukladno tome, osim glavnih uzroka, za svaki od analiziranih slučajeva naveden je i utjecaj ljudskog faktora kao preduvjeta koji je doveo do otkazivanja. U drugom dijelu rada opisani su tipovi progresivnog kolapsa kao kritičnog načina otkazivanja konstrukcija, s naglaskom na mostove, kao i pregled teorije robusnosti konstrukcija. Dane su smjernice i pristupi projektiranju u cilju sprječavanja katastrofalnih otkazivanja i stvaranja robusnijih konstrukcija. Opisani su načini postizanja robusnosti kod projektiranja novih te ojačavanja postojećih mostova, uz praktične primjere iz prakse., A review of forensic structural engineering, which is a strategy that follows after bridge failure, is presented in the paper. A detailed statistical analysis, and worldwide systematisation of available bridge failure data for the 1966-2020 period, are given. More than six hundred cases of partial or full collapse of bridges are analysed in detail, and causes that have led to their failure are examined. Failure of each of these bridges was in most cases not caused by a single factor, i.e. the main cause was most often just a trigger in the cause-and-effect sequence of events that contributed to such failure. Consequently, in addition to main causes, the influence of human factor, as a precondition leading to failure, is considered in each of the analysed cases. Types of progressive collapse, being a critical structural failure mechanism, are described in the second part of the paper, with an emphasis on bridges. An overview of the theory of structural robustness is also given. Design guidelines and approaches, aimed at preventing catastrophic failure and creating more robust structures, are presented. Methods for achieving robustness in the design of new bridges and in the strengthening of the existing ones are also described, and practical real-life examples are provided.