Assessing the seismic resistance class of concrete and masonry structures

Introduction . Concrete and masonry structures constitute the majority of old buildings in use. The aim of this research is to propose a methodology for assessing the seismic resistance of the cross-sections of elements ofconcrete and masonry structures. This research developes the previous research results in this area, which began in the USSR in the early 1980s. Materials and methods. The methodology of assessing the maximum accelerations and design seismic resistance classes for concrete elements of building structures is considered. For concrete elements the seismic resistance class is assessed by the position of the resultant force in the section (limitation of concrete tension) and by compressive stresses in concrete. The minimum seismic resistance class is assessed under the assumption of elastic work of the section. At the first stage, three values of the calculated peak accelerations are assessed, ensuring the following: the elastic work of the section, the limit state with the limit state coefficient К 1 = 0.5 and the limit state with the limit state coefficient К 1 = 0.25 respectively. Results. Basing on the resulting accelerations, one can assess the intensity of the design earthquakes using the Russian Standard scale of earthquake intensity. Conclusions. Basing on the research results, the authors assessed the intensity and repetitiveness of earthquakes resulting in various limit states of concrete and masonry structure sections, including the occurrence of section tension, the appearance of various cracks, complete section unloading, the appearance of spalls in the compressed zone of concrete, etc. These data are of interest to both facility owners and insurance companies.