Sökning: "internal erosion assessment"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden internal erosion assessment.

1. 1. Predicting surfacing internal erosion in moraine core dams

   Författare :Hans Rönnqvist; Anders Wörman; Hans Bergh; Kaare Høeg; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; internal erosion; internal stability; filters; moraine core; embankment dams; sinkholes; internal erosion assessment; Geoengineering and mining engineering; Geoteknik och gruvteknik;

   Sammanfattning : Dams that comprise broadly and widely graded glacial materials, such as moraines, have been found to be susceptible to internal erosion, perhaps more than dams of other soil types. Internal erosion washes out fine-grained particles from the filling material; the erosion occurs within the material itself or at an interface to another dam zone, depending on the mode of initiation. LÄS MER

3. 2. Internal Erosion Phenomena in Embankment Dams : Throughflow and internal erosion mechanisms

   Författare :Farzad Ferdos; Anders Wörman; Bijan Dargahi; Fredrik Johansson; Willi Hager; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Internal erosion modelling in porous material; Constitutive law of erosion for closure of continuum-mechanics-based balance equations for numerical modelling; High Reynolds-number turbulent flow; Flow laws; Coarse rockfill material throughflow; Computational Fluid Dynamics.; Civil and Architectural Engineering; Byggvetenskap;

   Sammanfattning :  In this study, two major internal erosion initiation processes, suffusion and concentrated leak mechanisms, which lead to both defect formation in a dam’s body and its foundation and high throughflow in dams subjected to internal erosion were studied. This understanding has the potential to facilitate numerical modelling and expedite dam safety assessment studies. LÄS MER

4. 3. On the Assessment of Internal Erosion of Dam Cores of Glacial Till

   Författare :Hans Rönnqvist; Kaare Höeg; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Soil Mechanics; Geoteknik;

   Sammanfattning : The objective of this study is twofold; on the one hand it investigates the susceptibility to suffusion of glacial till, and, on the other, it presents approaches to evaluate internal erosion susceptibility of dams composed of this type of core soil. Concentrated leak erosion, backward erosion, contact erosion, and suffusion erosion are the mechanisms associated with the initiation of internal erosion. LÄS MER

5. 4. Investigation of Suffusion in Glacial Till Dam Cores : Testing methods and critical hydraulic gradients

   Författare :Ingrid Silva; Jan Laue; Peter Viklander; Thomas Pabst; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; internal erosion; suffusion; glacial till; dam cores; dams; experimental investigation; hydraulic gradient; testing methods; cohesionless soils; granular soils; Geoteknik; Soil Mechanics;

   Sammanfattning : Suffusion is an internal erosion mechanism that occurs in embankment dams when fine grained particles in the dam core are washed out by seepage. Initiation of internal erosion depends mainly on three major factors: grain size distribution of the soil, stress conditions and hydraulic gradient; whilst its continuation depends on the properties of the filter. LÄS MER

7. 5. Suffusion of Glacial Till Dam Cores : An Experimental Investigation

   Författare :Ingrid Silva; Jan Laue; Peter Viklander; Cristina Jommi; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Geoteknik; Soil Mechanics;

   Sammanfattning : Suffusion, also called internal instability, is an internal erosion mechanism that occurs in embankment dams when fine-grained particles are washed out of the core soil matrix by seepage. Initiation of internal erosion depends mainly on three major factors: grain size distribution of the soil, stress conditions and hydraulic load; whilst its continuation depends of the filter properties. LÄS MER