Standard Practice for Determining the Number of Constrictions “m” of Non-Woven Geotextiles

Importancia y uso:

5.1 This practice provides a calculation method for determining the number of constrictions m of a non-woven geotextile (or of a layer of a composite material). This standard is not applicable to woven geotextiles, knitted geotextiles, heat-bonded geotextiles, or any other type of geosynthetic.

5.2 The number of constrictions represents the number of “windows” delimited by three or more fibers, in which soil particles could migrate. This value has been found to be relevant to explain the different filtration behaviors of non-woven geotextiles with similar opening sizes but different structures for various soil conditions (see Appendix X1 for details).

5.3 This value will be used in filtration research to evaluate the prediction of filtration efficiency and effectiveness of various non-woven geotextiles with similar opening sizes (Test Method D6767).

5.4 Interpretation of the significance of m as calculated using this standard shall be done with care, as some non-woven structures may not reflect the hypothesis used to establish the proposed equation (see Appendix X1 for details).

Subcomité:

D35.03

Volúmen:

04.13

Número ICS:

59.080.70 (Geotextiles)

Palabras clave:

clogging; constriction; filtration; geotextile; mechanically bonded; non-woven; number of constrictions; opening size; piping;