The generation of a strong shock wave during experiments requires the high explosive to be taken very close to the specimen. In case of a spherical charge the propagation of the shock wave is spherical, too. The shock wave does not hit the specimen simultaneously on the whole surface and the distribution of the incident pressure on the specimen is not constant. In order to generate a nearly constant pressure on a large surface of a specimen the distance between the specimen and the explosive charge should be large enough. For this reason the amount of the explosive charge must be in this case larger than in experiments with much shorter distances between the explosive charge and the specimen.
Carrying out experiments in countries with high population density by applying large amounts of high explosives is rather problematic or impossible. This problem can be avoided by using detonating foil (kind of a flat charge). Compared with other explosives the detonating foil is very expensive and not suitable for a large number of test series. However, it is possible to generate nearly planar shock waves by using line charges in a certain pattern. ... mehrA detonating cord can be used as a line charge. This kind of charge can be designed and prepared easily. Equally distributed loads can thus be generated by using small amounts of explosives.
The generation of planar shock waves by using a detonating cord will be herein designed by using the assumption of the theoretical mass of explosive by Sadowski. This analysis investigates the influence of the margin and the influence of the distance between the detonating cords. The theoretical results are compared with experimental results.