Effect of tufting density and loop length on the crushing behaviour of tufted sandwich specimens

A series of small scale specimens were tested to identify if local variations during the manufacturing process influence the energy absorbed during the crushing of tufted sandwich structures. Coupons with varying loop lengths and number of tufts were tested in quasi-static and dynamic edgewise compression. Results of the testing showed that the effect of a single tuft was captured at this small scale, whilst the tufting parameters changed the damage behaviour, including the response of the resin column during testing. Increasing the number of tufts at a single point, from one to two or three, gave rise to a greater energy absorption, but variations in loop length were less conclusive.