Three-dimensional analysis of water infiltration into the Gouhou rockfill dam using saturated-unsaturated seepage theory

The Gouhou Dam was a concrete-faced rockfill dam built in a steep canyon that collapsed in 1993 due to internal erosion during the initial reservoir filling. In this paper, the process of water infiltration into the originally unsaturated rockfill dam is studied using three-dimensional saturated–unsaturated seepage theory. The three-dimensional characteristics of seepage through the dam bounded by steep abutments, the effect of material anisotropy, and the effect of rockfill stratifications are studied. The three-dimensional results are compared with those from two-dimensional analyses. The three-dimensional simulations show that seepage water flows faster and the hydraulic gradients are greater near the abutment boundary in the dam. As such, the evolution of the seepage failure in the three-dimensional cases is faster than that in the two-dimensional analyses, and the two-dimensional analyses will underestimate the risk of seepage failure, particularly near the abutment boundary. If the materials in the ...

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