PSI - Issue 19

Yoichi Yamashita et al. / Procedia Structural Integrity 19 (2019) 123–129 Yamashita et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 5 Mockup of steel bridge deck specimen (upside down).

Fig. 6 Construction of arresters using gourd-shaped-insert-plates to fatigue crack at weld of steel deck and U-rib.

4.2. Mockup test result

Figure 7 shows the mockup test results regarding the relationship between fatigue crack length and number of cycles of fatigue loading before and after installing the gourd-shaped-insert-plate. Fatigue crack growth can be found before installing the arresters. Dot line shows the virtual line of the fatigue crack growth if no arrester were installed. On the other hand, after installing the arresters, the fatigue crack growth cannot be found even after 1x10 6 fatigue loading cycles meaning that the growing fatigue crack was arrested by installing the gourd-shaped-insert plates. This is due to the effect of the arrester by the crack closure force causing the reduction of stress concentration and stress intensity of the existing fatigue crack tip. Thus good performance of the gourd-shaped-insert-plates to arrest the fatigue crack can be found in the mockup test specimen of the steel bridge deck.