Originally Posted by CC12
Especially when you see something like a bridge collapse in Minnesota from lack of funding.
The collapse was due to a faulty design not the lack of funding.http://news.thomasnet.com/IMT/archiv..._collapse.html
Yesterday the National Transportation Safety Board (NTSB) said interim findings point to a design error that led to undersized gusset plates used in the I-35W bridge in Minneapolis, which killed 13 people and injured more than 100 when it collapsed.
Gusset plates are the large, flat steel connectors that hold load-bearing columns in place, tying together the angled steel beams of the bridge's frame.
As Minnesota's Pioneer Press reports:
The Interstate 35W bridge might have been doomed all along. Federal investigators pinpointed a flawed design that dates to when engineers first drew up blueprints in the mid-1960s as the primary reason the Minneapolis bridge fell into Mississippi River on Aug. 1, killing 13 and injuring 145.
More than a dozen steel support plates suspected in the bridge collapse were deficient in size, according to safety officials yesterday, and a routine inspection would not have uncovered the problem. The NTSB will not reach a final conclusion until autumn on why the I-35W bridge in Minneapolis collapsed into the Mississippi River, as the board's investigation is still on-going, but preliminary findings show 16 gusset plates were too thin to support the weight they held.
"During the wreckage recovery, investigators discovered that gusset plates at eight different joint locations in the main center span were fractured," safety board Chairman Mark Rosenker said at a news conference (via Reuters).
Safety board investigators discovered the original design process of the bridge led to a serious error in sizing some of the plates of the bridge's main skeletal structure.
According to a press release at the NTSB's Web site:
Undersized gusset plates were found at eight of the 112 nodes (joints) on the main trusses of the bridge. These 16 gusset plates (2 at each node) were roughly half the thickness required and too thin to provide the margin of safety expected in a properly designed bridge.
Here is the NTSB report http://www.dot.state.mn.us/i35wbridg...acy_report.pdf