A review of Beliche Dam

Abstract

"Crampton Price" de la Institution of Civil Engineers (London)Beliche Dam, a zoned earthdam with rockfill shouldersand a central clay core, experienced large collapse settlements\ud due to reservoir impounding and direct action of rainfall. Long-term field records of vertical and horizontal displacements are available as well as a set of largescale\ud laboratory tests on rockfill specimens. It has been the subject of several numerical analyses that failed to capture the relevant effect of weather conditions on the\ud behaviour of the dam. Recent developments in the constitutive modelling of rockfill allow a substantial improvement of modelling capabilities, and this is illustrated in\ud the paper. Laboratory test results under dry and flooded conditions were interpreted, and material parameters were identified. The complete history of dam construction,\ud impoundment and rainfall was then simulated by means of a coupled flow–deformation model. Deformations during construction and impoundment have been reproduced. Long-term deformations have consistently been related to rainfall records. In general, long-term\ud deformations are controlled by the varying wetting history of the dam shoulders and by an intrinsic deformation component. The wetting action comes to an end when the relative humidity of the rockfill reaches 100% for the first time. The paper also discusses scale effects and the role of rockfill permeability in the development\ud of deformations.Peer Reviewe

Model Test and Consolidation Analysis of Failure of a Loose Sandy Embankment Dam During Seepage

“…The specimens were compacted at diŠerent water contents so that the initial degrees of saturation diŠered: 10z, 20z and 40z. The dry densities slightly varied from 1.40-1.42 g/cm 3 . Vertical loads and volume changes of specimens were measured during the tests.…”

“…1. This is a river sand with Dmax (maximum grain size)＝2.0 mm, D50 (mean grain size)＝0.30 mm, Uc (uniformity coe‹cient)＝ 2.38, rs (density of soil particle)＝2.715 g/cm 3 , rdmax (maximum dry density)＝1.52 g/cm 3 , emax (maximum void ratio)＝0.927, and emin (minimum void ratio)＝ 0.598.…”

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From saturated to unsaturated conditions and vice versa

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