Визначення силових і енергетичних параметрів в процесах ударного руйнування матеріалів різної міцності та реологічних властивостей

The object of research is the processes of impact fracture of materials of different strengths and rheological properties. The problem of determining the force and energy parameters remains the lack of a generally accepted model of the processes of fracture of materials of different strengths and their rheological properties. In most crushing machines in the crushing chamber, the destruction of materials is accompanied by impact loads or is generally shock (impact crushers). The work includes studies of material destruction using the example of granite. The analysis of Johnson-Holmquist models was carried out, according to the plastic fracture model, which is designed to model the behavior of brittle materials, according to the fracture model of porous materials, especially concretes, which are subjected to large deformations, high strain rates and high pressure. It was found that during impact loading, maximum stresses arise on the impact surface, and also spread along the beam to the inner edges of the supports. The difference between the internal and kinetic energies for the JH2 body was 9.2 J, while for the JH1 body it was 15.3 J. The study on the pendulum impactor allowed to estimate the energy spent on the fracture of the material sample. It was established that if the crack crosses the intergranular boundary due to the action of local stress concentration, new cracks appear in the corresponding cleavage planes of neighboring grains, which require additional energy input to the sample. To estimate the dissipated energy in the fracture process, it was proposed to introduce an appropriate resistance coefficient. Based on experimental data, the resistance coefficient value was established for various rocks. The obtained research results can be used in the development and study of equipment for crushing materials. The value of the specific fracture energy can be used to study dynamic processes in building structures under excessive loads.