<p>Long-term operational experience of steam turbines shows the possibility of significant damage of various nature (mechanical and thermal fatigue, creep, corrosion, etc.) resulting from static and dynamic loading of critical structural elements, exposure to time-varying high temperatures, and corrosive environment. In some cases, such damage reaches critical dimensions, leading to catastrophic failures of steam turbines. One of the ways to prevent accidents related to the operation of turbines with critical damage is to identify the main operational and design factors that cause damage to turbine structural elements, as well as to study the intensity of damage accumulation under the influence of these factors in order to enable the prediction of the structural limit state. As operational causes of the initiation and development of local damage, such as a crack, we consider static (bending from the rotor’s weight and torsion at the stationary mode of turbine operation) and dynamic (torsional vibrations) loading of the turbine shaft. The stress concentration in the fillets and grooves and the complex geometry of the shafting are taken as the structural cause. A finite-element computational model of the K-210-130 steam turbine shaft and fracture mechanics approaches are used for the study. The conditions for the occurrence of scattered and localized damage such as edge and annular cracks under static and dynamic loading, the effect of stress concentration on the intensity of fatigue scattered damage are investigated. The effect of synchronization accuracy when connecting a turbine generator to the grid on the intensity of scattered and localized damage, such as an annular crack, is shown.</p>