PSI - Issue 46

5

Koji Uenishi et al. / Procedia Structural Integrity 46 (2023) 136–142 Koji Uenishi et al. / Structural Integrity Procedia 00 (2019) 000–000

140

a

b

Steel girder (flange)

Stud dowel

 L = 200 mm

Central position of the cartridge (behind the stud dowel in the front row)

 L =100 mm

Central position of the cartridge

Compression

Compression

Stud dowel

Cartridge

Tension

Tension

Larger tension

Larger tension

Compression

Compression

Larger tension

Larger tension

2.0  10 -4

Larger tension

Larger tension

Compression

Compression

 2.0  10 -4

Fig. 3. Positions of the centers of the cartridges, the stud dowels and the upper plate (flange) of the steel girder included in each numerical model, and the distributions of volumetric strain (tension positive) in the specimens A ((a); corresponding to Figs 1(a) and 2(a)) and B ((b); Figs 1(b) and 2(b)), at 20, 60, 100 and 140 microseconds (  s) after the application of EDIs. In both cases, first, compressive waves (depicted in bluish and greenish colors) are emitted from the cartridges, and then they are reflected to become dynamically tensile (in yellowish and reddish colors). The boundaries between the compressive (plus smaller tensile) parts and the regions of larger tension above the fracture strength can form the cup shaped fracture in (a) and horizontal fracture planes in (b), as indicated by the pink lines. Because of the symmetry of the models, only a half part of each specimen is shown.