Numerical Simulation of Yielding Supports in the Shape of Annular Tubes Under Static and Short-Term Dynamic Loading

Abstract

Abstract:Occurrence of extreme man-made impacts on buildings and structures has become frequent lately as a consequence of condensed explosives or explosive combustion of gas-vapor or air-fuel mixtures. Such accidents involve large human and economic losses, and their prevention methods are not always effective and reasonable. The given research aims at studying the way of enhancing explosion safety of building structures by means of yielding supports. The paper presents results of numerical studies (finite element, 3D nonlinear) of strength and deformability of yielding supports in the shape of annular tubes under static and short-term dynamic loading. The degree of influence of yielding supports was assessed taking into account three peculiar stages of deformation: elastic; elasto-plastic; elasto-plastic with hardening. The methodology for numerical studies performance was described. It was established that rigidity of yielding supports influences significantly their stress-strain state. The research determined that with increase of deformable elements rigidity dependency between load and deformation of yielding supports in elastic and plastic stages have linear character. Significant reduction of dynamic response and increase of deformation time of yielding supports was observed by increasing the plastic component. Therefore it allows assuming on possibility of their application as supporting units in reinforced concrete constructions.Keywords: yielding supports, strength, deformability, numerical simulation, finite element method, explicit dynamic, nonlinear effects ЧИСЛЕННОЕ МОДЕЛИРОВАНИЕ ПОДАТЛИВЫХ ОПОР В ВИДЕ ТРУБ КОЛЬЦЕВОГО СЕЧЕНИЯ ПРИ СТАТИЧЕСКОМ И КРАТКОВРЕМЕННОМ ДИНАМИЧЕСКОМ НАГРУЖЕНИИ О.Г. Кумпяк, Н.В. МещеуловТомский государственный архитектурно-строительный университет, г. Томск, РОССИЯ АННОТАЦИЯ: В последнее время участились случаи экстремальных техногенных воздействий на здания и сооружения, например, вследствие взрыва конденсированных взрывчатых веществ либо взрывного горения газо-, паро-или пылевоздушных смесей. Такие события могут повлечь большие человеческие и экономические потери, а методы их предотвращения или снижения последствий не всегда эффективны и рациональны. Целью данной работы является изучение способа повышения взрывобезопасности строительных конструкций за счет применения податливых опор. Представлены результаты численных (конечноэлементных, в трехмерной нелинейной постановках) исследований прочности и деформативности податливых опор в виде труб кольцевого сечения при статическом и кратковременном динамическом нагружении. Произведена оценка степени влияния податливых опор, имеющих три характерные стадии деформирования: упругая; упруго-пластическая; упруго-пластическая с отвердением. Приведено описание методики численных исследований и ее программной реализации. Установлено, что при увеличении жесткости сминаемых вставок зависимость между нагрузкой и деформированием опоры в упругой и пластической стадиях имеет линейных характер. Выявлено также значительное снижение динамической ре...

Analysis of changes in the survivability of building structures reinforced after an emergency dynamic impact in the context of assessing the security of buildings in the oil and gas industry

“…Therefore, to bring the structure into a state corresponding to the original one (before the impact), it is necessary to select such parameters of the reinforced concrete collar that, with a short-term dynamic impact, would provide similar survivability coefficients for the structure before and after its reinforcement, which together should not change the existing degree of protection of a critical infrastructure facility. The developed methodology and the survivability factor can also be useful, for example, in the design and assessment of the effectiveness of protective systems on pliable supports and systems that dampen vibrations to mitigate the dynamic impact on reinforced concrete structures under seismic, emergency shock, or explosive loads (Kumpyak et al, 2016;Chiaia et al, 2015;Mescheulov et al, 2017;Galyautdinov, 2017;Kumpyak and Mescheulov, 2017).…”

Optimization of flat-oval pipes and perspectives of their application in beam structures

“…All the calculations of the flat-oval and oval sections of the tubular profiles are performed under the assumption that they have the same initial blank (strip) with constant crosssectional area ( const A  ) and constant thickness ( const t  ). This premise restricts the change in the dimensions of the frames, which are determined by the complete flattening of the tubular profiles, which, as applied to compliant supports in the form of annular tubes, is defined as the elasto-plastic deformation stage with curing ( Figure 3) [8]:…”

Экспериментальное Исследование Динамических Характеристик Точечно Опертых Квадратных Плит

“…Следовательно, для динамических и сейсмических расчетов точечно опертых плит, применяемых в конструкциях зданий и сооружений, практический интерес представляет определение их динамических характеристик, частот, форм собственных колебаний и декремента затухания. Теоретические исследования этой задачи обычно производятся по приближенным методам расчета [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

“…Consequently, for dynamic and seismic calculations of point-supported slabs used in the structures of buildings and structures, it is of practical interest to determine their dynamic characteristics, frequencies, forms of natural vibrations and damping decrement. Theoretical studies of this problem are usually carried out using approximate methods of calculation [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”