Strength of Trucking Winch Straps: Effect of Age, Physical Damage, and Exposure to Real-World Conditions

Winch straps are used to secure cargo throughout the trucking industry, and play a critical role in ensuring the safety of cargo transportation. Very little research is available concerning the affects of real-world use, including mechanical damage and environmental exposure, of these straps. To provide some insights into this important and relatively unstudied question, this research performed tensile failure strength and stiffness measurements on a collection of straps used and subsequently removed from service by one trucking company, as well as new straps. This sample of straps, representing four different manufacturers, varied in age from 0 0 to 5 years and were affected by a wide range of cuts, abrasions, and other types of mechanical damage. The 30' long straps were cut to 28" lengths for testing in accordance with ASTM D6775. All straps were photographed prior to testing, so that the affect of any defects present could be evaluated in light of the failure strength. The identity of straps used as a group on the same truck was maintained, making it possible to analyze for differences between straps exposed to the same environmental conditions and between sets of straps from different trucks. The data readily show the effect of age and mechanical damage on failure strength and stiffness.