AS 3706.7:2003 Geotextiles—Methods of Test
9 PROCEDURE
The procedure shall be as follows:
(a) Secure the specimen in the sieve.
(b) Measure out a 50 ±0.01 g sample of one of the coarser-graded sand fractions and place it on the specimen. Ensure that the sand is dry and cool prior to use.
NOTE: The size should be chosen so that not less than 90% and as close to but not exceeding 99% is retained by the specimen. For some geotextiles, this may not be possible because of the size of openings. Some trial runs may be required to determine the required size.
(c) Place the receiver and sieve set on the sieve shaker and shake for 10 min.
(d) Measure and record the mass of sand collected in the receiver to within 0.01 g.Deduct this from the original quantity to determine the mass retained.
(e) Collect the sand retained by the geotextile together with the sand passing, for re-use.If the specimen has trapped an appreciable amount of the sand within itself, which cannot be easily removed by shaking it out, replace it with a similar specimen and recommence sieving with new sand of the same size. Where sand is contaminated with other sand fractions and is required for re-use, it shall be resieved and oven-dried prior to use.
(f) Repeat Steps (a) to (e) with successively decreasing sand grading sizes in accordance with Table 1 until less than 50% of the sample of sand is retained by the specimen if this is achievable.
(g) Repeat Steps (a) to (f), until a minimum of five specimens have been tested.
NOTE: Further testing may be required in accordance with Step (h) and Clause 10.3.
10.1 For each specimen
A graph (see Figure 1) shall be drawn (line of best fit) on log-probability paper through the points of percentage mass retained on the fabric versus diameter of particles which shall be taken as the mean size of the particle grading ranges (see Table 1). If separate specimens were used in accordance with Clause 9(e), these shall be regarded as a single specimen.