scholarly journals Safety Inspection Strategy for Earth Embankment Dams using Fully Distributed Sensing

2011 ◽  
Vol 8 ◽  
pp. 520-526 ◽  
Author(s):  
Pingyu Zhu ◽  
Y.B. Leng ◽  
Y.Zhou ◽  
G.L. Jiang
Keyword(s):  
Distributed Sensing ◽  
Embankment Dams ◽  
Inspection Strategy ◽  
Earth Embankment

WINDAM - Analysis of Overtopped Earth Embankment Dams

2006 ◽  
Author(s):  
Darrel M. Temple ◽  
Gregory J. Hanson ◽  
Mitchell L. Neilsen
Keyword(s):  
Embankment Dams ◽  
Earth Embankment

Stability of concrete macro-roughness linings for overflow protection of earth embankment dams

2002 ◽  
Vol 29 (5) ◽  
pp. 762-776 ◽  
Author(s):  
Pedro de Almeida Manso ◽  
Anton J Schleiss
Keyword(s):  
Precast Concrete ◽  
Flow Characteristics ◽  
Concrete Element ◽  
Unit Discharge ◽  
Embankment Dams ◽  
Earth Embankment ◽  
Failure Conditions ◽  
The Stability ◽  
Concrete Elements ◽  
Stability Concept

A macro-roughness lining system for the protection of earth embankment dams during overflow is presented. It consists of precast concrete elements placed on a drainage-separation layer. The main difference between this system and other existing concrete element systems is the stability concept, based on the self-weight of the blocks. Several types of elements were developed and tested in a physical model for a typical dam slope of 1V:3H. Failure conditions were identified after submitting the elements to increasing flow discharges. Furthermore, different foundation drainage and shear conditions between the elements and their foundation and different joint alignments were studied. Flow characteristics were observed and measured for quasi-uniform flow conditions. Based on the experimental results, a stability model was developed to compute the design safety factor. The model is based on the governing overturning equation (predominant failure mechanism) and on assumptions concerning the acting hydrodynamic forces, the hydrostatic uplift, and the concentration of air in the flow. Synoptic design charts were derived for 1V:3H dam slopes, allowing the rapid estimate of the lining characteristics as dimensions and weight for a certain withstood design unit discharge, for various margins of safety. The developed macro-roughness lining system is envisaged for the spillway rehabilitation of existing dams, but also for the design and construction of spillways of low dams (up to 30 m in height) and for the protection of overflow cofferdams.Key words: overflow dams, erosion protection, linings, macro-roughness, stability, drainage and spillways.

scholarly journals 2.5D resistivity modeling of embankment dams to assess influence from geometry and material properties

Geophysics ◽  
2006 ◽  
Vol 71 (3) ◽  
pp. G107-G114 ◽  
Author(s):  
Pontus Sjödahl ◽  
Torleif Dahlin ◽  
Bing Zhou
Keyword(s):  
Water Level ◽  
Resistivity Measurement ◽  
Data Interpretation ◽  
Internal Erosion ◽  
Water Level Fluctuations ◽  
Embankment Dams ◽  
The North ◽  
Fine Grained Soil ◽  
Earth Embankment ◽  
3D Effect

Repeated resistivity measurement is a potentially powerful method for monitoring development of internal erosion and anomalous seepage in earth embankment dams. This study is part of a project to improve current longterm monitoring routines and data interpretation and increasing the understanding when interpreting existing data. This is accomplished by modeling various occurrences typical of embankment structures using properties from two rockfill embankment dams with central till cores in the north of Sweden. The study evaluates the influence from 3D effects created by specific dam geometry and effects of water level fluctuations in the reservoir. Moreover, a comparison between different layout locations is carried out, and detectability of internal erosion scenarios is estimated through modeling of simulated damage situations. Software was especially developed to model apparent resistivity for geometries and material distributions for embankment dams. The model shows that the 3D effect from the embankment geometry is clearly significant when measuring along dam crests. For dams constructed with a conductive core of fine-grained soil and high-resistive rockfill, the effect becomes greatly enhanced. Also, water level fluctuations have a clear effect on apparent resistivities. Only small differences were found between the investigated arrays. A layout along the top of the crest is optimal for monitoring on existing dams, where intrusive investigations are normally avoided, because it is important to pass the current through the conductive core, which is often the main target of investigation. The investigation technique has proven beneficial for improving monitoring routines and increasing the understanding of results from the ongoing monitoring programs. Although the technique and software are developed for dam modeling, it could be used for estimation of 3D influence on any elongated structure with a 2D cross section.

Closed-system freezing of soil in earth dams and canals

1986 ◽  
Vol 23 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Chester W. Jones
Keyword(s):  
Closed System ◽  
Soil Conditions ◽  
Soil Density ◽  
Earth Dams ◽  
Embankment Dams ◽  
Loose Soil ◽  
Soil Structures ◽  
Earth Embankment ◽  
Frost Depth ◽  
Laboratory Experiences

Field and associated laboratory experiences with closed-system freezing in earth embankment dams and canals are presented. This type of freezing can cause a redistribution of soil density and moisture, which needs to be considered in the design of soil structures used as water barriers in cold regions. Frost-depth measurements made during the winter of 1978–1979 on two earth dams during interruption of their construction and on the Teton Dam remnant in the State of Idaho, U.S.A., are shown, along with associated soil conditions, air-freezing indexes, and insulating effects of snow and, for one dam, a loose soil cover. Some trends of density and moisture changes near the embankment surfaces were established. Keeping in mind known effects of freezing on soils, the paper raises questions about possible changes in soil density and shrinkage of embankments in contact with bedrock abutments that might adversely affect the safety of earth dams.Key words: dams (earth), canals, frost action, frost protection, soil density, soil moisture, soil shrinkage, soil tests, Teton Dam.

Spectrum Sensing Architecture and Use Case Study: Distributed Sensing over Rayleigh Fading Channels

2009 ◽  
Vol E92-B (12) ◽  
pp. 3606-3615 ◽  
Author(s):  
Chen SUN ◽  
Yohannes D. ALEMSEGED ◽  
Ha Nguyen TRAN ◽  
Hiroshi HARADA
Keyword(s):  
Fading Channels ◽  
Spectrum Sensing ◽  
Rayleigh Fading ◽  
Distributed Sensing ◽  
Rayleigh Fading Channels ◽  
Use Case
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