The Nanfang’ao bridge in eastern Taiwan suffered a catastrophic collapse on October 1, 2019, killing six and wounding a dozen others. Engineers are trying to determine how it happened. (Image courtesy of Taiwan News.)
The Nanfang’ao bridge suddenly fell apart when an oil tanker truck was crossing over the structure. The cause of the failure is still under investigation, but preliminary evidence points to corrosion in the bridge’s suspension cables as the possible cause. The 320-ton arch crashed down onto the truck and boats below the bridge, killing six people and injuring 12.
The Nanfang’ao bridge was 460 feet long and 59 feet high. It was the only steel single-arch bridge in Taiwan, the first bifurcated single-arch bridge in Asia, and one of only two bridges of its kind in the world.
The moment the bridge collapsed.
Video footage shows that the vertical cable at the center of the bridge snapped first. While the other cables should have been able to absorb and redistribute the extra load evenly, they didn’t—instead, the broken cable set off a domino effect of more snapped cables, leading to the bridge’s quick collapse.
Sung Yu-chi, dean of the Taipei Technology College of Engineering, theorized that the collapse of the arch could have been caused by the dissolution of the force equilibrium between the bridge and the arch.
Sung suspected that the cables were so weakened that when the first…