000004762 001__ 4762
000004762 005__ 20141119144551.0
000004762 04107 $$aeng
000004762 046__ $$k2002-06-02
000004762 100__ $$aGandola, Franck
000004762 24500 $$aCHARACTERIZATION OF AXI-SYMMETRICAL FLOW IN THE VADOSE ZONE

000004762 24630 $$n15.$$pProceedings of the 15th ASCE Engineering Mechanics Division Conference
000004762 260__ $$bColumbia University in the City of New York
000004762 506__ $$arestricted
000004762 520__ $$2eng$$aDye tracer and visualization techniques have been widely used for describing water flow patterns in soils and particularly, for determining the volumetric water content in one dimensional and two dimensional laboratory experiments. The present study describes a three dimensional laboratory experiment (axi-symmetrical condition) using color image analysis for determining the spatial distribution of the water content. The infiltration of a dye (fluorescein) mixed with water is achieved under axi-symmetrical condition in a Plexiglas chamber filled with an initially wet sand. Both infiltration and drainage processes are visualized under blue light filter and recorded on videotape. The image analysis technique used for determining the saturation state is based on the use of a limited color palette which allows us to quantify the evolution of the saturation state in the sand. Simultaneously, nine tensiometers connected to a data acquisition system, are used to determine the negative water pressure in the sand. The measurements of the suction confirm the existence of a second wetting front (after the dye solution flow) due to the initial mobile water content in the sand.

000004762 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000004762 653__ $$aimages, color, tensiometer, unsaturated, sand, axi-symmetry

000004762 7112_ $$a15th ASCE Engineering Mechanics Division Conference$$cNew York (US)$$d2002-06-02 / 2002-06-05$$gEM2002
000004762 720__ $$aGandola, Franck$$iAbriak, Nor Edine$$iHaverkamp, Randel$$iMatthews, Chris$$iBraddock, Roger$$iSander, Graham
000004762 8560_ $$ffischerc@itam.cas.cz
000004762 8564_ $$s186663$$uhttps://invenio.itam.cas.cz/record/4762/files/298.pdf$$yOriginal version of the author's contribution as presented on CD, .
000004762 962__ $$r4594
000004762 980__ $$aPAPER