Theoretical and experimental studies of silicon crystals irradiated with highenergy electrons (Е = 18 MeV) were made using the method of full integral X-ray reflectivity. To explain peculiarities of full integral reflectivity behaviour versus radiation dose and the order of reflection, the relationships of generalized dynamic theory of the Bragg X-ray diffraction in crystal comprising several defect types were used. The presence of several types of dominant defects in crystals allows closer tracing the dynamics of full integral reflectivity change versus the order of reflection and radiation dose, as well as estimating the contribution of each defect type to the diffusion component of X-ray scattering.