Dangerous Design

BRIDGE DESIGN: Investigators for the National Transportation Safety Board are now saying that the collapse of the Interstate 35W Bridge in Minneapolis may have been due to faulty design rather than deterioration. According to reports in the New York Times and other news media, the investigators suspect that the gusset plates (steel parts that connect the girders) weren't strong enough to support the loads.

Like many bridges constructed before the 1970s, the Interstate 35W Bridge had hundreds of gusset plates attached with rivets instead of bolts. So, this theory raises concerns about many bridges throughout the USA, and also about the accuracy of bridge inspections. Full story in the New York Times >>

TUNNEL DESIGN: Also in the news is the controversy surrounding the Big Dig tunnel in Boston. Last July ceiling tiles collapsed and a woman was killed. Her death stirred an outcry that the $15 billion tunnel was not safe. Now Powers Fasteners Inc., the company that supplied the epoxy glue for the tiles, has been charged with involuntary manslaughter. Full story in the New York Times >>