PSI - Issue 46

3

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

138

a

b

Cartridge Stemming

Cartridge Stemming

Reinforcing steel bars

Reinforcing steel bars

 L = 200 mm

 L = 100 mm

Stud dowel

Stud dowel

Cartridge

Cartridge

Steel girder

Steel girder

Fig. 1. Two different steel-concrete composite structures prepared for the field fracture experiments and modeled in the numerical simulations. A reinforced concrete slab is placed on top of a steel girder and stud shear connectors (stud dowels) [unit: mm]. The bars indicated in orange are reinforcing steel bars, and the blue and red sections in the figure are the stud dowels and cartridges producing electric discharge impulses (EDIs). The cartridges in blast holes are covered by stemming material. The horizontal spatial distance between each stud dowel in the axis direction of the specimen is (a) 200 mm (specimen A) and (b) 100 mm (specimen B) (modified after Wada et al. (2021)).

a

b

100 mm

 L = 100 mm

 L = 200 mm

Fig. 2. The two specimens A (a) and B (b) before (top) and just after (bottom) the action of EDIs. In the specimen A, with the horizontal distance between each stud dowel  L being 200 mm (a), cup-shaped fractures connecting the cartridges with the heads of the stud dowels, indicated by pink lines, appear. On the contrary, in the specimen B with  L being 100 mm (b), not only a horizontal fracture plane over the heads of the stud dowels but also another horizontal one containing the positions of the cartridges, again depicted by pink lines, emerges.