ISSN:0020-6024    

DOI:10.1080/02626666909493713

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

ISSN:0020-6024    

DOI:10.1080/02626666909493714

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

ISSN:0020-6024    

DOI:10.1080/02626666909493715

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The “non-Darcian” behaviour of water in soils is discussed considering the coupling that can arise between the different transport phenomena. In general, it is shown that there is a reason to expect that a difference in osmotic pressure will arise when solutions flow through porous media, and that due to that difference the resulting flow be related in a non-linear fashion to the applied pressure difference. Several numerical examples are presented illustrating this behaviour.

ISSN:0020-6024    

DOI:10.1080/02626666909493716

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The behaviour of unsaturated porous materials is described according to the procedure of FICK'S mixture theory. Hysteresis is included by use of the VOLTERRA'S integral form or by an approximative method using experimental results. Several mathematical models corresponding to physically significant situations are derived from the theory.

ISSN:0020-6024    

DOI:10.1080/02626666909493717

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

A summary is presented on the mechanisms of dispersion of miscible contituents in the liquid phase of porous materials. The transport is considered from both a microscopic (within the pore spaces) and macroscopic (an average of a representative number of pores) point-of-view. An attempt has been made to point out some of the problems associated with the use of the physically measurable macroscopic variables when investigating the basically microscopic phenomenon of dispersion. Some simple reactions between soil materials and chemical substances are discussed and some applications to tracer studies are presented.

ISSN:0020-6024    

DOI:10.1080/02626666909493718

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

In porous media, entrapped gas is considered as an important factor reducing the transmissibility of fluids through the medium.

ISSN:0020-6024    

DOI:10.1080/02626666909493719

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The purpose of this paper is to discuss the specific problems dealing with the use of Americium 241 for measuring the water content of soil sample by attenuation of low energy gamma rays. One of the advantages is that the optimum thickness of the soil sample is about 4 to 5 cm. However, one of the difficulties encountered is related to the determination of the absorption coefficient, which is generally lower than the theoretical value.

ISSN:0020-6024    

DOI:10.1080/02626666909493720

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The interpretation of tensiometers measurements requires special knowledge of the mechanics of equilibrium of the tensiometer with its environment. The classical concept of response time τ = (1/K′ S) of the system: porous cup (conductanceK') and manometer (sensitivityS) can be improved by taking into account the elasticity of the tubing. By analogy one can appreciate the role of entrapped air in the circuit. In general, it is possible to theorically observe the response characteristics of the tensiometer by imposing pressure step in the system and by studying the equilibrium response. Such tests showed certain anomalies of behaviour which can be attributed to very small bubbles of air entrapped to the internal wall of the porous cup.

ISSN:0020-6024    

DOI:10.1080/02626666909493721

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

We first define the interstitial pressure and the suction for sands and clays. Due to differences in behaviour of these two types of soils, the general equations for flow will be different.

ISSN:0020-6024    

DOI:10.1080/02626666909493722

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor