Resumen
Analysis of. physical processes that may cause the fragility and destruction of the lava-like fuel containing materials (FCM) of 4-th unit of Chernobyl Nuclear Plant (ChNP) has been carried out. The following processes are considered: influence of electric fields arising in medium with incorporated radio-nuclides, the role of the defect creation by irradiation of incorporated nuclides, residual mechanical strains caused by their cooling from the melting temperature in the time of the accident to the ambient temperature at present. It is shown that mechanical strains of such kind might be one of the causes of degradation and destruction of fuel containing materials. Different structure modifications of radiolysis hydrogen sources are discussed. Basic radionuclide?s, being in the Sarcophagus premises - a, ß- and ?- radiations are taken into account. It is shown, that the p-irradiators (Cs-137 and Sr-90) bring in generating of hydrogen the cardinal contribution. In dependence of nuclear spent material disparity, soluble forms of radionuclide?s concentrations, moisture saturation degree of fuel containing materials and water quality the account of hydrogen yield rate is presented. The estimations of the safe content of radiolysis hydrogen in the ?Sarcophagus" premises air in hermetic and interchange of air degree are offered.