ASSESSMENT OF RELIABILITY AND VITALITY OF SYSTEMS TAKING INTO ACCOUNT THE INTERRELATION OF ELEMENTS WITH SEISMIC EXPOSURE

Abstract

ObjectivesThe aim of the study is to develop a model for assessing the reliability of frame systems, taking into account the redistribution of forces between vertical structures when plastic hinges are formed in them from horizontal seismic effects.MethodThe research method is based on the analysis of the schemes of mechanisms for the transition of frame systems to limit states, as well as probability theory, random processes and system reliability.ResultsBased on the analysis of the paths of transition of statically indefinable frame systems to failure states due to the formation of plastic hinges at the junction points of the posts with crossbars, a block diagram of the system elements connection has been developed, presented as a separate redundancy scheme. The expressions for estimating the probabilities of switching off the conditional elements in the computational model and transitions of the system, both to the backup and to the failure states are presented. Expressions are proposed for assessing the survivability of frame systems with a decrease in static indeterminacy due to the formation of plastic hinges in structures. The calculation example is given.ConclusionThe proposed model for assessing reliability allows, in contrast to the parametric model, to evaluate the reliability of structures with regard to the redistribution of effort in structures with damage accumulated in racks in the form of plastic hinges, and to identify reliability reserves embedded in statically indeterminable systems under strong seismic effects.