A hydromechanical model for the analysis of concrete gravity dam foundations
DOI:
https://doi.org/10.24849/j.geot.2015.133.02Keywords:
Foundations of gravity dams, Hydromechanical model, Joint finite elementsAbstract
The explicit formulation of a small displacement model for the hydromechanical analysis of concrete gravity dam foundations, based on joint finite elements, is presented. The proposed hydromechanical model requires a thorough pre-processing stage in order to ensure that the interactions between the various blocks which represent both the rock mass foundation and the dam are always edge to edge. The mechanical part of the model, though limited to small displacements, has the advantage of allowing an accurate representation of the stress distribution along the joints. The hydraulic and the mechanical parts of the model are fully compatible. The hydromechanical model is validated using both a hypothetical situation of a gravity dam on a rock mass with a regular joint pattern and a real case of an operating dam, by comparison of the results with those obtained with a large displacement discrete model. Results of stability analyses are also compared, which lead to the conclusion that it is possible to assess the sliding stability of concrete gravity dams using small displacement models.
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