Block Element Method for Seepage/Stress Coupling in Fractured Rock Foundation of Gravity Dam

The uplift pressure on the foundation surface is one of the unfavorable factors for the stability of a gravity dam. The seepage/stress coupling character in the rock foundation may make the change of the seepage field which can lead to the change of the value of uplift pressure. In this paper, the seepage/stress coupling in fractured rock masses is studied by the two fields across iterative method with the help of block element method. A gravity dam is studied and the numerical analysis results show that the normal stress can affect the seepage character of rock masses greatly. In the region of high pressure stresses, the transmissivity deduces which can bring about the increment of gradient and velocity. This will bring an adverse impact on the stability of the dam. The coupling of seepage and stress in fractured rock foundation cannot be ignored in arithmetical analysis.

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DOI: https://doi.org/10.1029/wr022i013p01845

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