Numerical Analysis and Monitoring of an Embankment Dam During Construction and First Impounding (Case Study: Siah Sang Dam)

Monitoring embankment dams is of crucial importance. In earth dams, the pore pressures, earth pressures, and displacements occurring during construction and function, are measured at the time of the first impounding and exploitation by installing essential instruments and so the dam’s performance is evaluated and analyzed. Scope of the present research is the evaluation of the performance of Siah-Sang dam through using the results of instruments and back analysis which has been conducted by FLAC software.
The Mohr-Coulomb elastic-plastic model has been considered as the behavioral model of the dam and the effect of the upstream shell’s materials deformation has been modeled at the time of the initial impounding. Following that, comparing the results of the numerical analysis with the measured values, indicates that there is a proper consistency between these two values. Moreover, it was observed that the dam’s performance was suitable regarding the created pore water pressure, displacements and stresses in the construction period as well as during the first impounding. In addition, susceptibility of the hydraulic fracturing was assessed by calculating the arching ratio and it was concluded that this dam is secure in comparison with the behavior of other similar dams in Iran and the world.