Wyniki wyszukiwania - BazTech

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Zastosowanie metody konduktometrycznej do typowania stref o zmiennych parametrach filtracyjnych w obrębie podstawy wału przeciwpowodziowego

Cygal A., Stefaniuk M., Kret A., Klityński W.

Przegląd Geologiczny

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2015

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Vol. 63, nr 10/1

652--656

EN

The need to continuously monitor the flood embankment is necessary to introduce the measurement methods which give quick results in crisis situations. The protection of embankments as well as the prevention from floods are not only associated with the examination of the body river levee. Experience suggests that one of the problems involves the unknown geotechnical conditions of the levee base. Unfortunately, point geotechnical surveys carried out with a big measurement step were not able to fully identify the lithology variation over larger areas. This is caused by the high cost of drilling shallow wells. The application of non-invasive geophysical methods allows the completion of geotechnical research, and supplies additional information about the variability of geological medium. The structure in the area of the former river beds creates favorable conditions for carrying out geophysical surveys dependent on the variability of geoelectrical properties of rocks. This problem is solved by the use of conductivity method on the 100 m long part of the flood bank. This is recommended for quick and non-invasive measurements. A complex interpretation of geotechnical, hydrogeological and geophysical data provided information about the variability of geoelectrical parameters over this area and therefore made it possible to identify areas prone for greater filtration during high water levels.

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Pinhole test for identifying susceptibility of different horizons in less - derived soils to piping erosion

Nadal-Romero M. E., Verachtert E., Poesen J.

Landform Analysis

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2011

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Vol. 17

131-134

EN

The pinhole test is an empirical test based on the qualitative evaluation of the dispersivity (colloidal erodibility) of compacted fined-grained soils. This study evaluates the pinhole test device for the quantitative assessment of the susceptibility of soil horizons to piping. The experiments performed on different loess-derived soil horizons, with different hydraulic head and using distilled water show that the clay-enriched horizon (Bt horizon) is less susceptible to piping than the decalcified (C1) and the calcareous horizon (C2). This study demonstrates that the pinhole test is suitable for assessing the susceptibility of soil horizons to piping in a quantitative way.

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Impact of land use and soil properties on piping in Belgium

Verachtert E., Devoldere S., Van Den Eeckhaut M., Poesen J.

Landform Analysis

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2011

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Vol. 17

215-218

EN

Field observations and literature reveal that land use and soil characteristics play an important role in the development of piping. In this study, the hypothesis is tested that discontinuities in the soil profile favour piping erosion in loess-derived soils in a temperate humid climate. Abiotic characteristics (clay content, bulk density, Ksat, penetration resistance) and the biological activity in the soil were measured for each soil horizon until a depth of at least 40 cm below the pipes (ca. 1.30 m) for 12 representative soil profiles with different land use (pasture with and without collapsed pipes, arable land and forest). No clear discontinuities in abiotic characteristics were observed at soil depths where subsurface pipes occurred, but pastures with piping had significantly more earthworm channels and mole burrows at larger depths than pastures without piping, arable land or forest.