Risk Management on the Roads of Boston

July 12th, 2006 by

Here’s a problem for the amateur engineers out there. If you were going to hang something from a ceiling in your home, you’d probably want to at least put a toggle bolt behind it, so that the gravity pulling the object down would be countered by a more than equal force holding it up. You’d probably take into account the weight of the object. If someone suggested that you just run a screw into the ceiling plaster and back it up with some glue, you’d say they were crazy. With all the weight pulling straight down, it would take very little pressure to strip the screw out of the ceiling.
Now let’s imagine that you are hanging three ton ceiling tiles – hundreds of them – from the roof of a tunnel. Would you assume that you could support the tiles with bolts screwed vertically into the concrete ceiling and backed up by some epoxy glue? We’re talking the force of gravity here, with a significant weight pulling down. No engineer in his or her right mind would recommend such a solution, right? Well, you’ve obviously never been an engineer on Boston’s notorious Big Dig, the most expensive highway project in history: $15 billion and counting. All that money spent and already part of the recently completed project has collapsed.
Wrong Place, Wrong Time
Two days ago a section of the ceiling in a Big Dig tunnel collapsed onto the roof of a car, killing one occupant and injuring another. Angel Del Valle was driving through the Interstate 90 connector at about 10:45 Monday night, his wife, Milena, at his side, when huge chunks of concrete and steel came crashing down on his car, nearly flattening it. Angel managed to crawl out of the wreck. His wife was killed instantly. The collapse occurred at night, when few cars were in the tunnel. If it had occurred twelve hours later, we would have a major catastrophe of unprecedented proportions on our hands.
Rolling Heads and Safe Roadways
There are all kinds of investigations currently going on, including a criminal investigation for negligent homicide. But how much background in engineering would it take to determine that the design for hanging the heavy tiles was just plain stupid? How many inspections would be needed to show that the heavy tiles were at constant risk for dropping onto the traffic below? Civil engineers said the questions must go beyond the quality of workmanship to the tunnel’s design: Why were the concrete panels so heavy, weighing 2 1/2 to 3 tons apiece? Why were they there at all, since there was already a higher tunnel roof? And why did the failure of a single steel hanger send six to 10 of the slabs crashing down?
A lot of questions, with a few prime scapegoats readily at hand. The Turnpike Authority’s ubiqitous chairman, Matthew Amorello, appears ripe for the picking. Governor Mitt Romney, anxious to preserve his presidential ambitions, has taken steps to remove him. But whether Amorello stays or goes is hardly the point. People no longer feel safe driving on the most expensive three miles of roadway in history.
In the course of our daily existence, we all perform a rather blunt calculus, weighing the relative risk in our various activities. The Insider has long understood that driving is probably the riskiest activity that most of us do. As if the risk of sharing Boston’s roadways with distracted, short-fused whackoes were not enough, we now have to worry about the roads themselves. We take so much for granted, hurtling along in our 3,000 pound vehicles. What happened to poor Angel and Milena couldn’t possibly happen to us now, could it?