Research on anti-shockwave performance of the protective equipment for the head of a soldier based on shock tube evaluation

In order to optimize the structure and improve the performance of the head and face protective equipment for an individual soldier, firstly, the blast wave resistance tests of the bare-head model were carried out in real explosion field and shock tube environments, respectively. On this basis, the forward and lateral blast shockwave protective performance tests for helmet-head systems with different structures and protection levels were carried out by using the shock tube method. Finally, the peak values and durations of shockwave overpressure in the front, forehead, top, back, ear and eye areas of the helmet-head systems were compared and analyzed. The experimental results show that the blast shockwave test using a shock tube can be a substitute for the real explosion field test. When subjected to the effect of frontal shock wave, the peak value of the shockwave overpressure measured at the top measuring point of the two-half-helmet head model is about 1/6 compared with that of the nozzle outlet and 1/3 of the bare-head model as well as the integrated-helmet head model. The shockwave splits and relieves pressure at the split structure on the top of the two-half helmets and forms a superimposed reflection, resulting in a prolonged action time (5.5−8.5 ms), but a significantly decreased peak overpressure. For the rear measuring points, the peak overpressure (365 kPa) of shockwave measured by the integrated-helmet head model is slightly higher than that (303 kPa) measured by the two-half-helmet head model, and about 2.5 times as high as that (148 kPa) measured by the bare head model. By improving the structural airtightness of individual head and face protective equipments (such as wearing glasses, earmuffs or protective masks), shockwaves can be effectively prevented from entering the helmet-head systems, the stacking convergence effect can be weakened, and the protective performance of individual head and face equipments can be improved.