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Information × Registration Number 0218U003312, 0116U002340 , R & D reports Title The calculated modelsof forceresistance of complex stress spanreinforced concrete structures taking into account the action of low-cycle load of high levels popup.stage_title Head Karpiuk Vasyl Mykhailovich, Registration Date 31-01-2018 Organization The Odessa State Akademy of Building and Architecture popup.description2 The object of the study are statically determined and statically indeterminate one-, two- and multispan reinforced concrete beam-type structures, in which, in addition to the flat one, a general case of a stressed state can arise. The aim of the work is to investigate the influence of reversed and intermittent low-cycle high levels loading on the strength, deformability and crack resistance of span reinforced concrete structures, taking into account the constructive factors and their reinforcement;to improve the deformation calculation method;to developthe calculated models of their strength resistance, taking into account the physical nonlinearity of concrete and reinforcement;to developthestrength calculationgeneral engineering method. The methods of investigationis an applying of complex approach based on the theory of multifactorial experiments mathematical planning, on the deformation and deformation-strength methods for determining their bearing capacity using the phenomenological criteria for the concrete and reinforcement strength (including fatigue strength), their state diagrams, and methods of composite materials fracture mechanics, etc. Accordingtotheresearchresults, themainregularitiesofdeformation, crackingandfractureofspanreinforced concreteelementsinzoneofcombinedactionoftransverseforcesandbendingmomentsunderlow-cycleloadingwereestablished.Significant differences between the stress-strain state of specimens under the action of the reversed cyclic load were found, which are characterized by the formation and development of normal bracks in zone of pure bending and cross inclined cracks on their areas near supports.After the data processing using the COMPEX program, mathematical models of the basic performance parameters of the experimental elements were obtained, which together with the results of the reinforced concrete structures stress-strain statemodeling by means of nonlinear finite-element calculations with the help of PC "Lira SAPR" made it possible to develop the physical models of element resistance to the specified loading and to create the analytical calculated models of their fatigue strength. The results of the research are partially implemented to the current national standards for the design (SBN B.2.6-98: 2009, SBN B.2.6-100: 2010, SSTU B.B.2.6-156: 2010, SSTU-N B.2.6-205: 2015, SSTU B V.2.6-207: 2016). They are presented in 6 monographs, 5 textbooks, published articles, and they are appliedat the examination and reinforcement of beam reinforced concrete structures damaged by force influences, and also in educational process.5481 Product Description popup.authors Майстренко Оксана Федорівна Сьоміна Юлія Анатоліївна popup.nrat_date 2020-04-02 Close