Orthogonal Thought | Random musings from the creator of Cooking For Engineers and Lead Architect of Fanpop





Collapsing Freeways

Posted 29 April, 2007 at 10:50pm by Michael Chu
(Filed under: Current Events, San Francisco)

Collapsed 580This morning (at 3:42am), a tanker truck carrying 8,600 gallons of gasoline hit a guard rail, rolled-over, and exploded. Somehow the driver crawled out and walked off the freeway and found a taxi fueling up at a nearby Arco gas station at around 4:30am. The driver was taken to a hospital where he was treated for second degree burns. Meanwhile, the big news was unfolding - the gas tank that had exploded was still burning and temperatures had risen beyond 1,000°F, and at points going beyond 2,700°F. The truck happened to be positioned on what is called "The Maze" - a series of overpasses that interconnect the Bay Bridge into San Francisco (I-80), with I-880 and I-580 - and was burning on southbound 880 directly underneath the westbound 80 to 580 overpass. The heat was high enough to soften the giant steel screws holding the 580 in place above the 880 causing them to buckle and releasing a large section of the freeway to fall down onto the lower layer. The burning inferno continued and was able to melt some of the steel. The amazing thing is, no one was killed in this amazing disaster - which is incredible since this interchange is the busiest section of freeway in the San Francisco Bay Area. So far, the only injury related to the accident was the driver. (He has second degree burns on his hands, face, and neck, but is expected to live.)

The MacArthur Maze
During the 1994 Northridge Earthquake, several sections of three freeways collapsed. (I happened to be living only 1 mile from the epicenter of that earthquake and remember the experience quite clearly.) In that incident, the State of California announced a state of emergency and provided incentives for the construction crews to finish construction early which resulted in a sixty day completion of major repairs and 2 year total completion (vs. an estimated 3 year completion time). Today, Governor Schwarzenegger announced that the state would be using a similar plan to that used in Los Angeles during the Northridge quake.

I noticed a couple things while reading about this local disaster.  The lead article in the San Jose Mercury changed during the evening. The original article is no longer available - which sort of makes sense because the facts are old and out dated. However, I felt the original article was focused on the explosion while the new article had been reworked to begin with the story of the driver (as I did). They also altered a few of the quotes. The current article quotes Berkeley civil engineering professor Abolhassan Astaneh-Asl as saying "I think this was really the perfect fire". The original article's quote read "I think this was really the perfect fire, tragically". What was the reason for cutting the last word from the professor's quote?

Another interesting thing that was revealed by this disaster was that there is no certified burn unit in the East Bay. The driver was taken to a Kaiser in Oakland and later had to be transfered to a San Francisco hospital.

2 comments to Collapsing Freeways

Elise, April 30th, 2007 at 10:06 pm:

  • Hey Michael,
    This was pretty stunning, wasn't it? I'm so thankful that it happened in the middle of the night and that the driver lived through it.

Michael Chu, April 30th, 2007 at 11:16 pm:

  • Yeah, I totally agree. Now there's some news that suggests maybe the driver wasn't at fault. There might have been an earlier accident at that location and some debris may have punctured a tire on the tanker. The gasoline may have sloshed and tipped over the truck. It's amazing that the driver got out, found a taxi, and got to a hospital.