AbstractThe recent trend of increasing global terrorist attacks and identified vulnerabilities associated with critical bridges highlights the necessity to protect cable-stayed bridges from terrorist assaults. The cables are the most crucial load-carrying components within the envelope of a cable-stayed bridge, whose failure could result in the progressive collapse of the whole bridge structure with disastrous consequences. However, there is a very limited understanding of the blast effects on cables. This paper presents an experimental and numerical investigation of the blast performance of parallel wire cables under close-in explosions. Field blast tests were conducted on three identical parallel wire cable specimens with varying explosive charge weights. An equivalent beam–shell model was developed in LS-DYNA to reproduce the dynamic response of parallel wire cables subjected to close-in explosions and was comprehensively validated against the experimental results. With the validated numerical modeling techniques, the dynamic behavior of parallel wire cables in a realistic blast scenario of vehicle-borne improvise explosive devices (VBIEDs) detonated on the bridge deck was investigated. The results showed that high bending stress was induced in the cable end near the deck, indicating that the cable-to-girder anchorage zone is the most vulnerable position under the close-in blast scenario. Parametric analyses were carried out to further investigate the effects of cable dimension, prestressing force, cable length, and anchorage angle on the dynamic response of the parallel wire cables. It was found that the cables with smaller dimensions and higher prestressing force are more vulnerable, while the cable length and anchorage angle have limited effects on the performance. The results could be used in the safety evaluation and preliminary protective design of cable-stayed bridges under potential blast threats.

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