Hydraulic conductivity is a measure of the rate at which water flows through porous media. Because of the dipole properties of water molecules, electric field can affect hydraulic conductivity. In this study, the effect of radio-frequency (RF) waves on hydraulic conductivity is investigated. This is important both for the geophysical measurement of hydraulic conductivity as well as remediation ...

Research is being done to study the details and progress of soil erosion on levees and dams, including the formation and progression of rills and gullies on the slopes, and eventually to final breaching. These detailed observations of erosion differ from the typical predictions of only the maximum erosion or scour depths, for example around submerged bridge piers. Computer simulations and geote...

With increasing demand for better yield in agricultural areas, soil physical property representative measurements are more and more essential. Nuclear techniques such as computerized tomography (CT) and gamma-ray attenuation (GAT) have been widely employed with this purpose. The soil mass attenuation coefficient (μ(s)) is an important parameter for CT and GAT analysis. When experimentally deter...

Although people have always classified soils, it is only since themid 19th century that soil classification emerged as an important topic within soil science. It forced soil scientists to think systematically about soils and its genesis and developed to facilitate communication between soil scientists. It has also been the cause for much debate and confusion but two internationally accepted sys...

It is well-accepted that Archie's law only applicable to “clean” rocks and soils but fails in “dirty” ones where clay minerals possess an additional component of surface conductivity. Although several models, for example, Waxman-Smits model, were presented account this phenomenon, conductivity always inappropriately treated as constant, which actually holds at high salinities. The essential non...

it is known that native oil-degrading microorganisms are ubiquitous. they can be isolated from contaminated soils. in this study, biodegradation experiments were carried out to evaluate the efficiency of pollutant removal by adding the selected microorganisms. five mixed cultures and 3 single bacteria strains, pseudomonas sp., arthrobacter sp. and mycobacterium sp. were isolated from hydrocarbo...

The AASHTO code of practice for design of bridges shows that the ductility level for foundation is given equal to one. Bridges are classified in three classes. For class of essential and normal bridges a question for not to use ductility level due to the importance of bridges’ costs is become an important item in different countries particularly in Middle east. This paper aimed to study on pe...

This paper presents the application of a frequency-domain reflectometry (FDR) sensor designed for soil salinity assessment of sandy mineral soils in a wide range of soil moisture and bulk electrical conductivity, through the determination of soil complex dielectric permittivity spectra in the frequency range 10-500 MHz. The real part of dielectric permittivity was assessed from the 380-440 MHz,...