The past two days I was down in Taunton MA at a bridge which spans over Route 140. The rolled steel beam bridge with cover plates was built in 1959 and rehabilitated in 2004 with a new composite deck and railings.
With minor impact gouges on the underside of most of the beams it was only a matter of time before a truck not paying attention to the vertical clearance (14.90' Northbound and 14.74' Southbound) would hit the bridge. Something caused severe damage to Beam #8 (the South most beam in Span #1), deforming the web, bottom flange and cover plate. The impact also cause the web to crack at the diaphragm connections cracking the web to Beams #8 and #7 and braking the weld to Beam #6.
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| Checking out cracks |
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| POV of a bridge inspector |
The state added arrest holes to stop the cracks from propagating and to this date have not expanded past the arrest holes. One vertical rack along the weld on Beam #8 did not have an arrest hole and after doing a
Dye Penetrant Test we determined that the crack had not change since the last inspection.
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| Broken weld |
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| Cracked web with arrest holes |
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| Web pushed outward to the East |
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| Cleaning crack for dye penetrant test prep |
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| After adding dye |
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| Dye Penetrant Test complete showing full extents of the cracking |
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Section loss at beam ends |
1 comment:
that is fine engineering there !!!!!
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