This instrument is a standard test instrument used to evaluate the stress cracking strength of polyolefin geomembrane by the notch constant load tensile test. Mainly applicable to geomembrane used in landfills. Geomembrane is a waterproof barrier material based on polymer, such as polyethylene (PE) geomembrane, polyvinyl chloride (PVC) geomembrane, and chlorinated polyethylene (CPE) Geomembrane and various composite geomembranes, etc.

Provisions in Appendix C of CJ/T234-2006 "Industry Standards for Urban Construction of the Republic of China"

The test method is to place a dumbbell-shaped notched sample taken from a polyolefin sheet in a high-temperature surfactant under constant load tension, test and record the time to break of the sample, under different stress levels A series of test results can build a graph of the relationship between the stress level and its breaking time on the logarithmic axis. Environmental stress cracking resistance test of geomembrane. Standard test method 1 for evaluating the stress cracking strength of polyolefin geomembranes by notch constant load tensile test, abbreviated as "NCTL". The "NCTL" test method is to test the specimens under different constant tensile loads. A load of 20-65% of the material yield strength test is applied to the dumbbell-shaped specimen. The sample should be cut first, the depth of the cut is 20% of its thickness, and it is immersed in an active agent at a temperature of 50°C and a concentration of 10%. In this accelerated aging process, the time to failure of the sample is measured. The experimental results are drawn as a graph of the relationship between load and failure time. The NCTL test provides information on the plastic failure and brittle failure of the material. The stress cracking strength of the material is the transition time between these two failure modes.