Permeameter Research Articles

Comparison of flux-based and head-based methods for determination of near-surface saturated hydraulic conductivity

ABSTRACT The saturated hydraulic conductivity (K s) plays a crucial role in understanding water entry, redistribution, and hydrological processes at the soil–atmosphere interface. This study compared head-based [mini disk infiltrometer (MDI), automated SATURO, and laboratory permeameter (PM)] and flux-based [rainfall simulator (RS)] methods for determining near-surface K s through controlled laboratory measurements. Results showed that K s from RS aligned well with SATURO and PM estimates. The empirical MDI method (MDI-emp) provided K s estimates one order of magnitude higher than other methods, while an inverse estimation procedure using MDI measurements (MDI-inv) yielded results consistent with other methods. Statistical tests endorsed these findings. Three key conclusions were derived: (i) SATURO, RS, and MDI-inv were consistent in determining near-surface K s, (ii) RS was sensitive to the mathematical formulation adopted for K s determination, and (iii) MDI-emp method was unreliable for K s estimation. These findings underscore the potential of SATURO and MDI-inv as handy methods for K s evaluation.

Selection of geo-synthetic filter materials as drain envelopes in clay and silty loam soils to prevent siltation: A case study from Turkey

Geo-synthetic envelope materials are used in subsurface drain pipes to prevent the entry of soil particles into drains commonly installed to reclaim waterlogged salt affected lands. In-spite of its expensive cost, generally in the world, gravel and sand are traditional envelope materials to prevent the siltation in drain pipes. For this purpose, tube permeameter laboratory research was conducted for comparing geotextile with gravel and sand under the extraordinary hydraulic gradient regarding clogging and preventing siltation in the laboratory condition. Three type of geotextiles (woven and non-woven) and sand-gravel were tested on two type of soil (clay and silty loam). All geotextiles were better than sand-gravel envelopes for preventing the siltation and their clogging level did not create any risk for hydraulic conductivity. Key words: Envelopes, siltation, geotextile, sediment, hydraulic permeability, synthetic fabrics.

A permeameter designed to measure both hydraulic conductivity and dispersivity of consolidated rocks

A permeameter was designed to determine both the hydraulic conductivity (K) and longitudinal dispersivity (α )o f carbonates and sandstones in southeast Wisconsin. The permeameter can be used as either a constant head or a falling head permeameter. K was determined by measuring the flow-through volume per given time interval, whereas α was determined by the breakthrough of a saline tracer after applying a continuous tracer source. All sources of error such as side flow and evaporation combined produced an apparent flow of about 0.015 mL/h. This translated into a lower detection limit in hydraulic conductivity of 5 × 10 -11 m/s. Reproducibilities of both hydraulic conductivity and longitudinal dispersivity measurements were within a 20% error margin. The permeameter was used to test hydraulic conductivity and longitudinal dispersivity of 75 carbonate samples and 26 sandstone samples. Resume : Un permeametre a ete concu pour determiner tant la conductivite hydraulique (K) que la dispersivite longitudinale (α) de carbonates et de gres dans le sud-est du Wisconsin. Le permeametre peut etre utilise comme permeametre soit a charge constante, soit a charge variable. Le parametre K a ete determine en mesurant le volume d'ecoulement par intervalle de temps, alors que α a ete determine par l'apparition d'un traceur salin apres l'application d'une source continue du traceur. Toutes les sources d'erreur telles que l'ecoulement lateral et l'evaporation combinees ont produit un ecoulement d'environ 0,015 mL/h. Ceci s'est traduit par une limite inferieure de detection de conductivite hydraulique de 5 × 10 -11 m/s. Les reproductibilites des mesures tant de la conductivite hydraulique que de la dispersivite longitudinale se situaient a l'interieur d'une marge d'erreur de 20%. Le permeametre a ete utilise pour mesurer la conductivite hydraulique et la dispersivite longitudinale de 75 echantillons de carbonate et de 26 echantillons de gres. Mots cles : conductivite hydraulique, dispersivite, permeametre, essais de laboratoire. (Traduit par la redaction)

Equations for the Radiofrequency Magnetic Permeameter

Equations for the Radiofrequency Magnetic Permeameter

Advances in the design and application of the radiofrequency permeameter

Advances in the design and application of the radiofrequency permeameter

Some developments and simplifications in permeameters

Some developments and simplifications in permeameters

A permeameter for magnetic testing at magnetizing forces up to 300 oersteds

A permeameter for magnetic testing at magnetizing forces up to 300 oersteds