- Journal
- Année
- 2014
- Pages
- 1451-1453
Abstract
Nickel-chromium (NiCr) wires change their resistance when stretched and, consequently, when included as part of a Wheatstone bridge, can be used in a similar way as a strain gage with appropriate calibration. In previous work Chocron et al. [1, 2] have shown that the strain in a fabric can be estimated using the waves recorded with NiCr wires using some simplifying assumptions on how waves propagate. This paper extends the technique to a Kevlar composite material and shows a thorough study of the waves recorded for various configurations: 1) eight wires in the same layer at increasing distance from the impact point, 2) eight wires in different layers but all at the (approximately) same distance from the impact, 3) the first two configurations were repeated with wires woven in the fabric and wires sandwiched between the layers, 4) wires in a `` gap'' configuration, only woven in a small portion of the fabric, 5) wires woven in cross patterns and, 6) wires embedded through the thickness of the composite. In general every configuration was tested five times, three below the ballistic limit of the panel and two above the ballistic limit.