## 3 Research Results and Discussion
### Carbonization
Moreover, a general decrease in crack resistance (caused by carbonization) facilitates greater penetration of CO\({}_{2}\) due to cracking and, consequently, causes an increase in the carbonization depth [134]. Similarly, the process of carbonization is accelerated by high temperatures [134]. Thus far, no carbonization prediction models have been developed under conditions of exposure to ionizing radiation [30]. 1.2 Corrosion of Reinforcement in Reinforced Concrete Structures Under the Effect of Gamma Radiation  
Reinforced concrete structures are characterized by the formation of a passivating layer with a pH of 13 at the interface between the reinforcement and concrete, which prevents the general corrosion of reinforcement steel [152]. Carbonization, radiolysis, and chloride ions penetrating into concrete can destroy this passivating layer. As a result, the process of general corrosion will occur [153]. In this case, operating temperature conditions have a great effect [152]. And the same about penetrating chlorides, which retain moisture inside the concrete structure and reduce the specific electrical potential of concrete resistance, in addition to the chemical reaction [153]. The immediate effect of gamma radiation on the corrosion rate of steel elements in various environments is studied in several works [56; 57; 58; 59; 60; 61; 64; 66; 67; 68; 69; 154; 155; 156; 157]. Thus, the preliminary evaluation of corrosion of carbon steel container packages under aerobic conditions shows that gamma irradiation increases the corrosion potential [155]. On the contrary, the study [57] provides information that the corrosion rate of carbon steel increases six-fold under the effect of water and gamma radiation. [PERSON] et al. (2008) examine the effect of gamma radiation (at a dose rate of 11 Gy/h and 0.3 kGy/h and temperatures of 30 and 50 \({}^{\circ}\)C, respectively) on steel corrosion in groundwater environments. Their conclusion is that corrosion processes are accelerated, and some oxidation is observed at higher dose rates [58]. Hence, gamma radiation accelerates steel corrosion processes in the media that facilitate radiolysis. In [67], low-carbon steel X65 was irradiated with a gamma radiation source of Co\({}^{60}\) under aerobic groundwater conditions until the accumulated values of 1, 2, and 3 MGy were attained. According to [PERSON] et al. [67], gamma radiation boosts the number of defects in the lattice structure of metals, reduces the overall electrical potential, and accelerates processes of local and general corrosion. In the review section of their study, the authors [67] found that, in general, gamma radiation accelerates the corrosion of carbon steel at dose rates of 3 kGy/h but decelerates this process at higher rates exceeding 13 kGy/h. According to [68], a dose rate of more than 5 Gy/h is needed to accelerate the general corrosion of corrosive materials. However, some authors claim that the corrosion rate was comparable with that without irradiation at a dose rate of 11 Gy/h [61]. It follows from an earlier review [158] of works on steel corrosion that the effect of gamma radiation, even at high dose rates (about \(10^{5}\) R/h), is insignificant for carbon steel during corrosion in aqueous solutions with a low degree of salinity and low magnesium content, but if chlorides are present, such an effect is insignificant up to a dose rate of 3\(\cdot\)10\({}^{2}\) R/h. In environments saturated with magnesium ions, high doses (\(10^{5}\) R/h) lead to a significant increase in the corrosion rate. For dose rates in the range of 10 to \(10^{3}\) R/h, the corrosion rate can decrease under the action of gamma radiation, which, as [PERSON] and [PERSON] suggest, is associated with the ability of the radiation field to cause crystallization of protective iron deposits. Table 2 contains a summary of studies on the corrosion of metal structures subjected to the effect of gamma radiation in various environments and at various temperatures.