A History of Research and a Review of Recent Developments

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Penetration and fragmentation
Figure 7.12 Penetration experiments on cylinders, L/d=1 (steel cylinders into sand)
(from Stilp et al., ref. 7.18).
spheres, partly because the cylinders became flattened and ‘mushroomed’ at
the higher impact velocities. The greater the length/diameter ratio, the greater
the scatter, and at ratios of 10 the projectiles bent on impact. This caused
deviations from the original trajectory, made worse when the cylinders also
broke into pieces. Values of p/d for cylinders with L/d=1, 5 and 10 are shown
in Figures 7.12, 7.13 and 7.14.
The prediction of projectile penetration into rock and cemented soils by
means of a numerical procedure was examined by Schoof, Maestas and Young,
who reported their work in 1989 [7.19]. The Sandia National Laboratories at
Figure 7.13 Penetration experiments on cylinders, L/d=5 (steel cylinders into sand)
(from Stilp et al., ref. 7.18).