Over the last decade, new national regulatory documents on the design and assessment of the technical state of building structures, in particular steel ones, have been put into force in Ukraine to replace relevant former USSR regulations. The experience of applying new national regulatory documents indicates certain incorrect provisions, which can potentially cause catastrophic consequences in case of failure of steel building structures of corresponding facilities and(or) hazardous production capacities. The paper presents the analysis of Ukrainian regulations to check compliance of available methodologies for computer strength justification of steel structures. It is established that current regulatory documents of Ukraine do not contain a description of methodologies and procedures (formulae) with regard to calculations of steel structures on resistance to brittle fracture and cyclic crack resistance. The analysis of a number of publications was performed to define methods for the calculation of steel structures to check endurance, cyclic crack resistance and resistance to brittle fracture.

This paper considers issues on the life definition of category A structures for the buildings of CC3 class of consequences (liability) that may have defects at the beginning of operation or damages accumulated in the process of operation. The calculations to check resistance to cyclic loads shall be made for the stated structures at the design stage. The research includes analysis of requirements of Ukrainian and international regulatory documents for the calculation of structure components for quasistatic, low-cyclic fatigue and cyclic cracking resistance.