Internal Erosion and Rehabilitation of an Earth-Rock Dam

Flores-Berrones, Raúl; Ramírez-Reynaga, Martín; Macari, Emir José

doi:10.1061/(asce)gt.1943-5606.0000371

Cited by 54 publications

(17 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Internal erosion and piping are the main causes of failure in earth dams, contributing to almost 50% of all failures; the other major cause is overtopping (Fell and Fry, 2007;Flores-Berrones et al, 2010;Foster et al, 1998;ICold, 2013;Minguez et al, 2006). For a new dam, potential internal erosion and piping can be avoided through good design and close supervision during construction, especially of the core, and the provision of an appropriate filter to intercept the formation of any concentrated leaks (Benahmed and Bonelli, 2012;Fell and Fry, 2007).…”

Section: Introductionmentioning

confidence: 98%

An assessment of veracity of filter criteria for earth dams

Vakili

Selamat

2014

Proceedings of the Institution of Civil Engineers - Geotechnica

View full text Add to dashboard Cite

The core of an earth dam is normally made of clayey base soils and protected by a sandy filter. Designing the filter can be very challenging considering the various criteria established today. This study commences with a review of three prominent criteria referred to in designing filters by the indirect method. No-erosion filter tests are then carried out involving 11 fine-grained, base soil samples with different properties; these are a highly dispersive soil, a soil with a medium to high degree of dispersion, a soil with a low-plasticity silt (ML) classification and a soil with a broad gradation curve. These tests represent the direct method. A comparison of results arising from the two methods shows that designing filters the indirect way, by following established criteria alone, is not always safe. Hence, it is proposed that such designs should be experimentally verified using no-erosion filter tests. Furthermore, instead of following the prevalent criteria in the indirect design method, the perfect filtering method for highly dispersive soils and the reduced particle size distribution method for broadly graded soils are proposed to be used, with merits given for each method. Finally, the paper recommends certain filter criteria from the literature for base soils with a moderate degree of dispersion and an ML classification respectively.

show abstract

Section: Introductionmentioning

confidence: 98%

An assessment of veracity of filter criteria for earth dams

Vakili

Selamat

2014

Proceedings of the Institution of Civil Engineers - Geotechnica

View full text Add to dashboard Cite

show abstract

“…Both such rapid rise of the phreatic line and reverse seepage in the case of sudden drawdown can lead to internal erosion of the dam and instability of the dam slope [3,4]. Research on slope instability due to rapid drawdown is plentiful [3,[5][6][7], but works on unsteady seepage and slope stability during rapid filling, and especially during wet-dry cycles with crack formation, are scarce [8,9]. The research carried out here seeks to help fill in this knowledge gap.…”

Section: Introductionmentioning

confidence: 99%

Unsteady Seepage Behavior of an Earthfill Dam During Drought-Flood Cycles

Marenče

Bricker

2018

Geosciences

View full text Add to dashboard Cite

Climate change with extreme hydrological conditions, such as drought and flood, bring new challenges to seepage behavior and the stability of earthfill dams. Taking a drought-stricken earthfill dam of China as an example, the influence of drought-flood cycles on dam seepage behavior is analyzed. This paper includes a clay sample laboratory experiment and an unsteady finite element method seepage simulation of the mentioned dam. Results show that severe drought causes cracks on the surface of the clay soil sample. Long-term drought causes deeper cracks and induces a sharp increase of suction pressure, indicating that the cracks would become channels for rain infiltration into the dam during subsequent rainfall, increasing the potential for internal erosion and decreasing dam stability. Measures to prevent infiltration on the dam slope surface are investigated, for the prevention of deep crack formation during long lasting droughts. Unsteady seepage indicators including instantaneous phreatic lines, equipotential lines and pore pressure gradient in the dam, are calculated and analyzed under two assumed conditions with different reservoir water level fluctuations. Results show that when the water level changes rapidly, the phreatic line is curved and constantly changing. As water level rises, equipotential lines shift upstream, and the pore pressure gradient in the dam’s main body is larger than that of steady seepage. Furthermore, the faster the water level rises, the larger the pore pressure gradient is. This may cause internal erosion. Furthermore, the case of a cracked upstream slope is modelled via an equivalent permeability coefficient, which shows that the pore pressure gradient in the zone beneath the cracks increases by 5.9% at the maximum water level; this could exacerbate internal erosion. In addition, results are in agreement with prior literature that rapid drawdown of the reservoir water level is detrimental to the stability of the upstream slope based on embankment slope stability as calculated by the Simplified Bishop Method. It is concluded that fluctuations of reservoir water level should be strictly controlled during drought-flood cycles; both the drawdown rate and the fill rate must be regulated to avoid the internal erosion of earthfill dams.

show abstract

“…4 sieve size (ASTM 2006a). Rockfill material is widely used for the construction of rockfill dams (Cooke 1984;Dascal 1987;Khalid et al 1990;Prato and Matheu 1991;Elgamal 1992;Uddin and Gazetas 1995;Hunter and Fell 2003;Milligan 2003;Papalou and Bielak 2004;Xing et al 2006;Peiris et al 2008;Costa and Alonso 2009;Seo et al 2009;Flores-Berrones et al 2011;Walberg et al 2013) and railroads (Janardhanam and Desai 1983;Diyaljee 1987;Indraratna et al 1998;Haque et al 2007;Anderson and Fair 2008;Nimbalkar et al 2012;Sevi and Ge 2012). Therefore, extensive experimental research on rockfill material has been conducted for the further application of rockfill in the construction of rockfill dams and railroads.…”

Section: Introductionmentioning

confidence: 99%

Strength and Deformation of Rockfill Material Based on Large-Scale Triaxial Compression Tests. I: Influences of Density and Pressure

Xiao

Liu

Chen

et al. 2014

J. Geotech. Geoenviron. Eng.

View full text Add to dashboard Cite

A series of large-scale triaxial compression tests were conducted to investigate the strength and deformation behaviors of Tacheng rockfill material (TRM) in relation to the initial void ratio and initial confining pressure. The critical state friction angle of TRM was expressed as a linear function of the logarithm of the initial confining pressure. The excess peak state friction angle and excess characteristic state friction angle of TRM were formulated as linear equations of a revised relative dilatancy index to capture the influences of density and pressure on the peak state and characteristic state friction angles. The initial elastic modulus, tangent modulus, and secant modulus of TRM were dependent on the initial void ratio and initial confining pressure. In addition, a formulation incorporating density and pressure was proposed to simulate the initial elastic modulus of TRM. The volumetric and deviatoric strains of TRM at the critical state were also dependent on density and pressure. The critical state line of TRM in the e 2 lg p9 space descended with a decrease in the initial void ratio.

show abstract

Internal Erosion and Rehabilitation of an Earth-Rock Dam

Cited by 54 publications

References 4 publications

An assessment of veracity of filter criteria for earth dams

An assessment of veracity of filter criteria for earth dams

Unsteady Seepage Behavior of an Earthfill Dam During Drought-Flood Cycles

Strength and Deformation of Rockfill Material Based on Large-Scale Triaxial Compression Tests. I: Influences of Density and Pressure

Contact Info

Product

Resources

About