Difficulties in analytical fire safety assessment of steel bridges, using the provisions of EU design standards and legislation

摘要

Today, there is a complete lack of appropriate regulatory provisions governing the fire safety assessment of bridges, in particular, specifying the load criteria under fire exposure, with which primary and secondary load-bearing elements should comply. Similarly, the new harmonized bridge structure design standards do not put forward in their decisions any substantive provisions which would allow conducting this type of analysis. In accordance with the preamble of the latest set of European structural design standards "The Member States of the EU and EFTA recognize that Eurocodes serve as reference documents for the following purposes: - as a means to prove compliance of building and civil engineering works with the essential requirements of Council Directive 89/106/EEC, particularly Essential Requirement No 1 (Mechanical resistance and stability), and Essential Requirement No 2 (Safety in case of fire);[...]". In fact, it appears that, with regard to Essential Requirement No 2 this clause - in particular in relation to objects other than buildings - is dead and does not translate to any specific guidelines, which would allow the achievement of the objective. The authors shall carry out a thorough analysis of legislation and design standards in force in the EU Economic Area, indicating their flaws and lack of coherence. They shall provide a proposal for how to carry out a load assessment of bridge structure elements under fire exposure and specify criteria which, in their opinion, strongly justify the need to conduct such analyses.