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Information × Registration Number 0224U000128, 0122U002466 , R & D reports Title Modeling of dynamic behavior of structural members made of materials with complicated physical and mechanical properties and quasi-static propagation of cracks due to hereditary properties of the material popup.stage_title Head Zhuk Yaroslav O., Доктор фізико-математичних наукSelivanov Mykhailo F., Доктор фізико-математичних наук Registration Date 02-01-2024 Organization Department for special training National academy of science of Ukraine at Kiev University popup.description2  In the frame of Timoshenko-type refined shell theory, the statement and numerical solution of the problem on prediction of coupled electro-thermomechanical response and durability of viscoelastic cylindrical three-layer shell with piezoelectric sensors under axisymmetric resonance vibration is studied for different types of the shell facets constraint condition. The problem statement is based on the amplitude constitutive relations for cyclically deformed material as well as complex moduli concept. Nonlinear problem is solved numerically with the use of iterative approach. For the most power-intensive first axisymmetric bending mode, influence of the mechanical and thermal boundary conditions as well as accounting for in-plane shear strain and thermal dependencies of electro-mechanical properties of the shell constituent both passive and piezoactive materials on frequency curves for maximum deflection amplitude, sensor electric parameter and dissipative heating temperature are investigated in details for the case of external harmonic pressure loading. Technique for the shell life prediction with the use of critical value of the dissipative heating temperature is proposed. Thermal criterion is applied to estimate the durability of the shell for both steady and transient regimes. An approach is developed to predict the workability time interval for forced resonance vibration of the shell under load amplitudes exceeding the critical amplitude level. With making use of the theory developed, the problem of compensation of axisymmetric resonant vibration of the shear compliant inelastic cylindrical shell with piezoactuators under electromechanical loading is studied. Possibility of the active damping of forced vibration by the piezoactuator usage is established with accounting for shell shear strain. The methodology for solving problems related to delayed fracture of mode I cracks in spatial structural members made of transversely isotropic viscoelastic materials has bee Product Description popup.authors Bogdanova Olga Vitalievna Gusak Vitaliy O Zhuk Yaroslav О. Selivanov Danylo M. Selivanov Mykhailo F. Fernati Pavlo Viktorovych popup.nrat_date 2024-01-02 Close