Discrete element models applied to failure analysis of concrete dams’ foundations – a new discontinuity constitutive model
DOI:
https://doi.org/10.14195/2184-8394_108_1Abstract
A numerical model based on the discrete element method is presented, for the study of dam foundations in rock masses. A constitutive model for discontinuities was developed, which takes into account the softening of the cohesive component of shear strength and of the tensile strength. The field of application of the present model comprises studies of rock engineering structures that require a representation of the behavior of joints and interfaces, including deterioration and failure processes, namely concrete-rock interfaces, concrete lift joints in dams, and the propagation of non-persistent joints in rock masses. The constitutive model for joints was implemented in the discrete element programme 3DEC. A comparison with results of laboratory tests of fracture of a concrete beam showed a good agreement between numerical and experimental data. The model was also applied to the study of the safety of a concrete arch dam, for a failure scenario involving rising of the water level and sliding on a fault in the rock mass.
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References
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