A Laboratory Study of the Effect of the Function of Hydraulic Conductance on Modeling of Seepage from Earth Dams

Document Type : Research Paper

Authors

1 Assistant Professor, Department of Water Engineering, Urmia University

2 Associate Professor, Department of Water Engineering, Urmia University

Abstract

Seepage analysis through earth dams is employed to determine the water loss. Moreover, as the magnitude of pore pressure in dam body is calculated using seepage analysis, this analysis plays an important role on the stability analysis in these types of structures. As the hydraulic conductivity of the earth dam materials, is considered as one of the effective parameters on the magnitude of seepage, an experimental model of an earth dam was constructed, and by the accurate measurement of saturated vs. unsaturated hydraulic parameters of materials (and by use of Disk Infiltrometer), the flow through the experimental model was simulated, employing by Seep/W as a finite element based model. The results of the study revealed that application of unsaturated hydraulic conductivity function, rather than constant saturated permeability, presents more accurate results. A comparison of the model results with the obtained data confirmed that the differences between model results and the real data diminishes, as by approaching the Phreatic Line limits. Furthermore, a comparison of results revealed that, in the transient state of seepage under drawdown conditions, the model predicted the draining of the body occurring more slowly than when the function of hydraulic conductivity being employed rather than constant saturate hydraulic conductivity.

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References

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Iranian Journal of Soil and Water Research
Volume 45, Issue 3 - Serial Number 3
December 2014
Pages 299-307

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