This is an index test used to measure the force required to continue or propagate a tear in woven or non woven geotextiles by the trapezoid method. The trapezoidal test is useful for quality control and acceptance testing but is unsuitable for design applications. This test method is suitable for most geotextiles that include woven fabrics, non-woven fabrics, layered fabrics , knitted fabrics and felts that are used for geotextile applications.
An isosceles triangle is marked on a 200mm x 76mm rectangular test specimen The 2 non parallel sides are gripped in parallel flat faced clamps and the required strain rate applied. A continuous tear is propagated in this way and the maximum force recorded.
- AS 3706 speed limited to 250mm/min
- ASTM D4533 speed limited to 250mm/min