Numerical analysis of static behavior of embankment dam under changes in the core inclination (Case Study: Azad Dam)

In the design of embankment dams, the vertical or inclination of the core has its own advantages and disadvantages according to technical and economic considerations. In each of these options, it is necessary to pay attention to the amount of seepage, deformations and stresses created in the body and foundation of the dam, as well as stability. In addition, the control of the arching caused by different stresses and subsidence in different levels and areas, which can lead to hydraulic failure of the dam, should also be considered. In this study, while analyzing the static behavior of the "Azad" dam in real condition (with a vertical core) in GeoStudio software, analysis of seepage, stress-strain, arching and slope stability with different core inclination (zero , five, 10, 15, 20 and 22 degrees relative to the vertical) at end of construction and steady-state seepage have also been studied and compared. The results showed that for a given depth, with increasing the angle of inclination of the core from the vertical position, the seepage through the dam body and foundation (especially for angles greater than 15 degrees) and the vertical displacement of the core central line increased. Also with increasing the angle of inclination, the average stability safety factor of the downstream slope of the dam increased imperceptibly but for the upstream slope especially for angles greater than 15 degrees, there was a significant decrease of 22.6 percent. The trend of increasing the total vertical stress along the central core line with increasing depth for different angles of the core did not change significantly. In the case of arching, except in the height range of 0.3 of the height of the crest, the probability decreased with increasing inclination angle of the core.