Publications
Long duration shock pulse shaping using nylon webbing
Typical shock testing requirements specify shock pulses of several hundred to several thousand g's, with pulse duration usually less than a few milliseconds. A requirement to qualify a shipping container to a head-on tractortrailer crash environment led to the development of a new test technique capable of low-g (< 50 g), long-duration (> 100 ms) shock pulses. This technique utilizes nylon webbing engaged in tension to shape the pulse produced by the interaction of two sleds on an indoor track. A combination of experimental and computational methodology was used to successfully develop the test technique to solve a specific testing requirement. The process used to develop the test technique is emphasized in this paper, where a prudent balance between experiment and analysis resulted in a cost effective solution. The results show that the quasi-static load-elongation behavior of the nylon webbing can be used to adequately model the dynamic behavior of the webbing, allowing design of the experimental setup with a simple computational model. The quasi-static load-elongation measurements are described along with the development of the computational model. Results of a full-scale experiment are presented, showing that the required shock pulse could be achieved with this test technique.