The effect of slit orientation and length on the tear behavior of S8210 used for freight wagons tarpaulin

PVC-coated fabrics are widely used in tarpaulin applications due to their durability and flexibility. This study investigates the tearing behavior of PVC-coated fabric specimens containing central straight and inclined slits, sampled from S8210-type tarpaulins used in freight wagons. Uniaxial tensile tests were performed on both intact and slit specimens. Horizontal slits having lengths of 5, 10, and 20 mm, as well as inclined slits of 20 mm at 30°, 45°, and 60° angles, were analyzed. The results reveal two distinct fracture modes: progressive and abrupt failure. Inclined slits exhibited a progressive, Z-shaped crack propagation pattern while the horizontal slits lead to a more sudden failure. Key fracture parameters, including maximum fracture force, fracture energy, and the influence of slit geometry on fracture strength, were determined. A critical opening length beyond which the tarpaulin's repair is recommended was also identified. The paper translates the theoretical concepts of breaking energy in a directly measurable parameter (aech). This can be investigated directly on site by the maintenance personnel and based on the reading and proposed tables for this material, can make safety decisions.