We had a bridge beam seat/pad failure for the same reason.
A morning radio personality reported a significant "bump" at the end of the bridge. Upon inspection, and bridges are fully inspected a minimum of 2 years, the bridge seats on the end support, i.e., abutment, had cracked and slipped from the anchor bolts for the support bearings. The taller concrete bearing pads, to account for the side slope of the deck, were supposed to be reinforced with rebar stirrups since concrete is weak in tension.
The other contributing factor was the Lucite®️ bearing at the first pier. It had a slot to allow span expansion but, upon installation, had the retaining nut tightened down much too snugly, preventing the longitudinal expansion movement.
Thus, a lot of the expansion force was in the abutment end, cracking the unreinforced concrete seat/pads that dropped a few inches, creating the "bump."
The bridge was about 25 years old at the time of the failure.
Sometime, in a relevant thread, I'll share the other scary situation we found while on the reconnaissance inspection for this issue.
** Edited by TomTurkey at 7/17/2026, 10:28:45 AM
Thread Replies (10)
Highrise buckled steel story: Crucial reinforcing steel was never installed
-- MikeVT85
Jul 17, 2026 at 09:24 AM ET
MikeVT85
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07/17/26 09:24 AM ET
Special Inspections for Building Structures are typically performed
-- VT BronzeBacker
Jul 17, 2026 at 03:07 PM ET
VT BronzeBacker
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07/17/26 03:07 PM ET
eh . . . I prefer blaming the city inspector. **
-- MikeVT85
Jul 17, 2026 at 08:51 PM ET
MikeVT85
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07/17/26 08:51 PM ET
We had a bridge beam seat/pad failure for the same reason.
◄
-- TomTurkey
Jul 17, 2026 at 10:24 AM ET
TomTurkey
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07/17/26 10:24 AM ET
Might have used more Simpson strong ties.**
-- PhotoHokieNC
Jul 17, 2026 at 03:11 PM ET
PhotoHokieNC
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07/17/26 03:11 PM ET
We also had a major concrete box culvert (or frame with a bottom slab).
-- TomTurkey
Jul 17, 2026 at 10:34 AM ET
TomTurkey
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07/17/26 10:34 AM ET
Sounds about right. My initial guess was that either the...
-- MP4VT2004
Jul 17, 2026 at 09:42 AM ET
MP4VT2004
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07/17/26 09:42 AM ET
IBC requires structural observation by the engineer as well so it'll be
-- KeithHokie89
Jul 17, 2026 at 12:07 PM ET
KeithHokie89
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07/17/26 12:07 PM ET
Eh....it's New York, so probably some organized crime angle as well**
-- JoesterVT
Jul 17, 2026 at 09:53 AM ET
JoesterVT
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07/17/26 09:53 AM ET