Standard Test Method for Static Puncture Strength of Geotextiles and Geotextile-Related Products Using a 50-mm Probe
Theory:
ASTM D6241 is also commonly referred to as the CBR Puncture Resistance test. The California Bearing Ratio was adapted to replace both the Mullens Burst test D3786 and the Geomembrane puncture test D4833. Both of the later tests have been deemed to produce too much variability because of the inconsistent nature of woven and non-woven fabrics. This procedure provides a much more uniform stress on the sample which better simulate real world conditions.
Geometry:
The standard square sample is clamped down in the non-slip jig. There are 4 clamping screws that must be tightened to secure the sample. The diamater of the puncture implement is 50mm and it is flat and rounded. There is also a standard specification for the hole opening which can be found in our official literature page.
Solution:
The clamping jig and flat rounded puncture probe are offered either as individual items or as a package. Both pieces of the puncture fixture attach to the UTM by means of a 5/8" clevis pin style adapter.
Analysis:
Similar to other puncture tests, the main calculation is really just an average of the peak load over a handful of individual tests. The variability between tests is also calculated and the deviation is taken.