A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Perméabilité des géotextiles et perméamètres
Abstract Effectuer une mesure réaliste de la perméabilité des géotextiles est moins aisé qu'il n'y paraît au premier abord. En appliquant aux géotextiles la théorie de l'Hydraulique des milieux poreux, et en se fondant sur des expérimentations effectuées à l'IRIGM (Université de Grenoble) et à l'Institut Textile de France, sur quatre perméamètres différents, nous avons montré la nécessité de conditions d'essais rigoureuses. Nous avons notamment comparé les résultats obtenus avec deux fluides (air et eau), nous avons montré l'intérêt d'utiliser de préférence un nouveau paramètre, la perméance intrinsèque ki/b, et enfin nous avons corrélé la précision de mesure à la valeur du nombre de Reynolds. En conclusion, nous proposons un nouveau modèle de perméamètre répondant aux conditions imposées plus haut.
Summary - One of the most frequent tests carried out on these products studies the permeability to fluid flow normal to the geotextile plane. Measuring this property is of dual interest: - geotextiles used in civil engineering often play a hydraulic role, so knowledge of their permeability is important for this; - the permeability of a geotextile to a fluid is very sensitive to structural modification (porosity, fibre diameter) so its measurement provides an excellent means of assessing the homogeneousness of the product. But whatever the first impression may be, it is not easy to make precise measurement of the permeability of geotextiles. The present-day geotextile industry proposes a very wide range of products which feature very different thicknesses and porosities. This tendency will certainly become more marked. Most permeameters in current use are only appropriate for a partial range of geotextiles, either the most permeant (high k/b) or the least permeant (low k/b). The value of permeability measured should be independent of test conditions. This imposes a severe control of temperature and pureness of the fluid, measurement of the apparatus loss of pressure, optional choice of section S of the geotextile sample, and a restriction of rate of flow. This leads to defining a new parameter-permeance or permittivity (k/b). By applying the theory of hydraulics of porous media to geotextiles and basing calculation on information obtained from testing carried out at the IRIGM (University of Grenoble) and the Institut Textile de France (French Institute of Textile) on four permeameters (water or air models) the authors show that measurement accuracy can be correlated to the Reynolds number ℛr. Consequently a new model of permeameter is proposed in compliance with conditions imposed above.
Perméabilité des géotextiles et perméamètres
Abstract Effectuer une mesure réaliste de la perméabilité des géotextiles est moins aisé qu'il n'y paraît au premier abord. En appliquant aux géotextiles la théorie de l'Hydraulique des milieux poreux, et en se fondant sur des expérimentations effectuées à l'IRIGM (Université de Grenoble) et à l'Institut Textile de France, sur quatre perméamètres différents, nous avons montré la nécessité de conditions d'essais rigoureuses. Nous avons notamment comparé les résultats obtenus avec deux fluides (air et eau), nous avons montré l'intérêt d'utiliser de préférence un nouveau paramètre, la perméance intrinsèque ki/b, et enfin nous avons corrélé la précision de mesure à la valeur du nombre de Reynolds. En conclusion, nous proposons un nouveau modèle de perméamètre répondant aux conditions imposées plus haut.
Summary - One of the most frequent tests carried out on these products studies the permeability to fluid flow normal to the geotextile plane. Measuring this property is of dual interest: - geotextiles used in civil engineering often play a hydraulic role, so knowledge of their permeability is important for this; - the permeability of a geotextile to a fluid is very sensitive to structural modification (porosity, fibre diameter) so its measurement provides an excellent means of assessing the homogeneousness of the product. But whatever the first impression may be, it is not easy to make precise measurement of the permeability of geotextiles. The present-day geotextile industry proposes a very wide range of products which feature very different thicknesses and porosities. This tendency will certainly become more marked. Most permeameters in current use are only appropriate for a partial range of geotextiles, either the most permeant (high k/b) or the least permeant (low k/b). The value of permeability measured should be independent of test conditions. This imposes a severe control of temperature and pureness of the fluid, measurement of the apparatus loss of pressure, optional choice of section S of the geotextile sample, and a restriction of rate of flow. This leads to defining a new parameter-permeance or permittivity (k/b). By applying the theory of hydraulics of porous media to geotextiles and basing calculation on information obtained from testing carried out at the IRIGM (University of Grenoble) and the Institut Textile de France (French Institute of Textile) on four permeameters (water or air models) the authors show that measurement accuracy can be correlated to the Reynolds number ℛr. Consequently a new model of permeameter is proposed in compliance with conditions imposed above.
Perméabilité des géotextiles et perméamètres
Gourc, J. P. (author) / Thelliez, Ch. (author) / Sotton, M. (author) / Leclercq, B. (author)
Matériaux et Construction ; 14 ; 303-317
1981-07-01
15 pages
Article (Journal)
Electronic Resource
French
| Engineering Index Backfile | 1933
Porosite et permeabilite des betons
| Engineering Index Backfile | 1936
Une diagraphie de permeabilite par methode acoustique
| Online Contents | 1982
Mesurein situ de la permeabilite des Argiles
| Online Contents | 1982
Perméabilité au gaz de bétons endommagés
| Taylor & Francis Verlag | 2002