Sunday, July 18, 2021

1967 I-40 Bridge over Arkansas River and 2002 Collapse

(Bridge Hunter; NTSBSatellite)

"Built 1967; rehabilitated 1983. Collapsed on May 26, 2002 after being hit by a barge, killing 14. Reopened to traffic July 29, 2002." [Bridge Hunter] The bridge collapsed because a 2-barge tow allided with it because the captain blacked out as the tow neared the bridge. I-40 was closed for 65 days. [8:00]

NTSB, p15

Both this photo and a satellite image shows that they added dolphins in front of most of the piers on both sides.
Matthew Wong, Jan 2020

The two piers holding up the navigation span are massive, but that is probably because of the extra weight that they have to hold and because of the deeper river current that they have to resist. What I don't understand is why the other piers on the east side (background above and left side below) are more massive than those on the west side. Note in Figure 15 how much lower the river level is compared to Matthew Wong's photo above.
NTSB, p33

Somehow the pier protectors must float because they are near the first crossbar below the deck in Matthew's photo but well below that crossbar in these photos. And I'm confused because 18B shows that a pier that holds up a navigation span looks spindly.
NTSB, p53

The accident was caused because the captain blacked out when his tow was near the bridge. I personally have experienced a sudden blackout. I was in my 20s and setting on the toilet. The next thing I knew, I heard my wife frantically calling my name. When the rest of my brain came to I realized that I was sprawled out on the floor face down. My fall forward must have been stopped by the side of the bathtub because my head was close to it and the top of my head hurt. I was able to get up by myself and felt fine except for the sore head. I've never had a blackout since then.

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