ASTM D6241-14 pdf free.Standard Test Method for Static Puncture Strength of Geotextiles and Geotextile-Related Products Using a 50-mm Probe.
This test method is an index test used to measure the force required to puncture a geotextile and geotextile-related products. The relatively large size of the plunger provides a multidirectional force on the geotextile. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
This test method for determining the puncture strength of geotextiles is to be used by the industry as an index of puncture strength. The use of this test method is to establish an index value by providing standard criteria and a basis for uniform reporting.
4. Summary of Test Method
4.1 A test specimen is clamped without tension between circular plates and secured in a tensile or compression testing machine, or both. A force is exerted against the center of the unsupported portion of the test specimen by a steel plunger attached to the load indicator until rupture occurs. The maximum force is the value of puncture strength.
7. Sampling
7. 1 Lot Sample—ln the absence of other guidelines, divide the product into lots and take lot samples as specified in Practice D4354.
7.2 Laboratory Sample—Consider the units in the lot sample as the units in the laboratory sample. For the laboratory sample, take a full width sample of sufficient length along the selvage or edge of the roll so that the requirements of 7.3 through 7.5.2 can be met. Exclude the inner and outer wraps of the roll or any material containing folds, crushed areas, or other distortions not representative of’ the sample lot.
7.3 Remove test specimens from the laboratory sample in a randomly distributed pattern across the width with no specimen taken nearer the selvage of fabric edge than 1/20 of the fabric width or 150 mm (6 in.), whichever is the smaller, unless otherwise specified.
7.4 Test Specimens—From each unit in the laboratory sample. cut the specimens so that the edge of specimen will extend beyond the edge of the clamp by 10mm (0.39 in.) in all directions.
7.5 Number of Specimens—Unless otherwise agreed upon. as when provided in an applicable material specification, take a number of tcst specimens per laboratory sample such that the user may expect at the 95 % probability level that the test result is not more than 5.0 % of the average above or below the true average of sample. Determine the number of specimens per sample as follows:
7.5.1 Reliable Estimate of v—When there is a reliable estimate of v based upon extensive past records for similar materials tested in the user’s laboratory as directed in this test method, calculate the required number of specimens as follows.