519.6
531.4

оптичні методи
напружено-деформований стан
граничний стан
тріщина
триплекси
optical methods
stress-strain condition
boundary condition
crack
triplex

Представлено результати розроблення нових оптичних експериментально- розрахункових методів визначення напружено-деформованого стану (НДС) об’єктів – методу поглинання (МП) та методу дифузного поверхневого розсіювання (МДПР). Дія МП базується на п’єзооптичному ефекті поглинаючого середовища, а МДПР – на перерозподілі інтенсивностей дзеркальної та дифузних складових дифузно відбитого поверхнею потоку при локальній зміні її кривизни. Модифіковано поляризаційно-оптичний метод дослідження НДС для малих за величиною картин оптичної анізотропії. Запропоновано фізико-механічний критерій граничного стану діелектриків – критерій тензора діелектричної проникності (ТДП). На основі модифікованого поляризаційно- оптичного методу та критерію ТДП проведено комплексне дослідження НДС та граничного стану багатошарових структур (триплексів) з концентраторами.
In the article the authors presented the data on the development of new optical experimental and computational methods for determining the SSS objects – the absorption method (AM) and the method of diffuse surface scattering (MDSS). The effects of AM are based on piezooptic effect of absorbing environment. The theoretical justification of the method is derived from the joint solution of the Maxwell-Neumann’s equations linking the shift components of the dielectric penetration tensor (DPT) with the Bouguer-Lambert- Beer equation, describing the passage of light through the absorbing environment. Experimental realization of the AM deals with the measuring of the absorption intensity of light polarized in the principal areas. The method makes possible to find separately the main stresses and strains immediately rather than their linear combination, as it occurs in the interference methods. The MDSS effect is based on measurements of intensity redistribution of mirror and diffuse components of the luminous flux, reflected by its diffuse scattering surface under local change of its curvature. The authors obtained the formulae for the coefficient values of intensity moments in the crack tip threshold for the sharp stress state, as well as evaluated the dynamics of the «neck-like formation area extension». The authors proposed options of surface deformation meters, operating on the MDSS effect in two real solutions. In one of them an active element of the meter is a curved plate, and in the other – the gouge with diffuse reflecting surface. To estimate the boundary condition of the machine parts and structures made of dielectrics the authors proposed the physical-mechanical DPT. According to this criterion the alteration of the physical factors complex (temperature, humidity, radiation) not only the limit of strength is changed, but also the expression for the equivalent stress due to the alteration of the value of the optical and mechanical constants ratio. The authors modified the polarization and optical method to determine the small size pictures of optical anisotropy. These measurements were conducted in two points in the area of elastic asymptotic in the crack tip threshold. The authors obtained the formulae for finding SIF in the case of heterogeneous stress state. The modified polarization and optical method as well as physical and mechanical criterium of DPT boundary condition were applied for the complex study of multilayer structures (triplexes) with the possible availability of crack-like effects in their component parts (elements); the kinetics of inorganic silicate glass fracture being researched. The authors analyzed the data on the fracture of the organic glass plates with threshold cracks. The authors simulated the impact of the frame on SIF during penetration of surface cracks into transverse ones in glueing layer. Basing on the conducted research the impact of framing and heterogeneity on the strength of triplexes has been estimated and the effective constructive option has been chosen.