I answered someone else on this question 1. multiply the 1.5th of the expected value of the geotextile sample by the size of the geometric cloth. 2. If you do not know the expected value, it should have a standard tensile strength range, with the tensile strength multiplied by the cross-sectional area of geotextile (thick by the width) to find the force value. 3. If you do not know, it is recommended to choose 50KN or 100KN equipment. Of course, if you need to test the geotextile was cut into a width that is particularly small, then you can use a small amount of force, but it is recommended if you choose from 5KN and 50KN election 50KN good.