Высокоэнергетическая обработка материалов
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tion of the phenomenon in entire volume of a glass sample. Since the process of
interaction of a body with glass needs determination of a considerable number of
coefficients it is reasonable to carry out tests depending on barrier structure (sin-
gle- or multilayer), glass thickness, methods of its hardening, velocity and material
of impacting body, and so on. A bird, stone, bullet, a fragment or other objects
might be impacting bodies. The essential role plays in such situation a comparable
analysis of data obtained from computer simulations and measurements. The use of
these results gives a possibility of elaborating specific data for optimization of
glass shields structures for buildings, appliances, and ground and above-water
transportation means as well as airborne objects.
Our works concerned theoretical analyses and experimental investigations of
dynamic destruction of glass shields. In theoretical studies relevant models for
elastic-brittle bodies as well as 2D and 3D computer codes based on the free points
method [1, 2, 3, 4] used for simulation of impact phenomena were developed while
in experimental investigations a measurement stand was built and impact processes
were tested using velocity meters and electro-optic camera.
1. Equations of the problem
The question of interaction of a metallic projectile with a shield (target) is
situated in the field of interaction of high-speed bodies. Mathematical-physical de-
scription of these dynamic processes is pretty complex since it has to take into con-
sideration elastic, plastic, or viscous effects in dynamically deformed solid bodies
and formation of cracks in solids or even their fragmentation.
To describe solids behavior in high dynamic loads a model of elastoplastic
body for metallic projectiles was used while for glass shields a model of elasto-
plastic-brittle body was applied [5, 6, 7, 8, 9, 10].
A set of equations expressing laws of conservation and constitutive relations for
dynamic interactions in the 3D variant has the form described and presented in [11,12].
2. Investigations of dynamics of destruction areas propagation in glass
targets after projectile impact
Investigations of the process of glass target penetration using electro-optic
camera were aimed at obtaining a digital record (a few frames in specified time in-
tervals) of a picture of propagation of destruction areas in glass targets after projec-
tile impact [13]. Such record can be very suitable for verification of computer
modelling results with real data of propagation of destruction areas in glass targets
and for final specification of coefficients in strength models.