Marquette Interchange Problems 1

[BadgerPE]

Anyone else think it is a little odd that cracks found in the column Monday are already being claimed by HNTB? Is this typical in projects of this magnitude or do they usually get tied up in court?

http://www.whbl.com/news/articles/2010/sep/03/marquette-interchange-project-already-showing-crac/

 

[bridgebuster]

design errors happen - fortunately ones like this don't happen too often.

Perhaps the designer knows it's at fault and figures it's easier to settle now rather than end up on the short end of a lawsuit and risk future business with the DOT.

 

[BAretired]

If HNTB found a problem when they reviewed their design, they took the most responsible action possible, i.e. getting traffic off the structure. It is likely also the most economical solution.

BA

 

[JedClampett]

It's a little surprising to me, not that the error happened, but in that there was consequences so soon. It seems that bridge engineers are so conservative that, even if they made a mistake, it wouldn't cause a failure. More likely, it would just eat into the factor of safety.

 

[ACtrafficengr]

Maybe the car manufacturers can learn something from HNTB about taking responsibility for their design flaws.

"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

 

[hokie66]

Kudos to HNTB for acting quickly. It must have been a simple and obvious problem, but a lot of them are.

 

[Qshake]

The design is 2 years old. No one should be reviewing the design and finding problems now. They should have reviewed the calcs properly before signing off.

With today's rush, rush, rush it's imperative that we adapt our checking system to cover the calcs equally as quickly. Another thing to consider is multiple office work and the need to coordinate with everyone when major, major projects are underway.



Regards,
Qshake

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.

 

[msquared48]

Sounds like there may be at least one vacancy at HNTB.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[BAretired]

Thinking of applying, Mike?

BA

 

[msquared48]

No. I'm too old to be hired.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[JedClampett]

To me, it didn't sound like they were just getting around to reviewing the calculations, found an issue and closed the bridge. The bridge cracked, they looked at the design and found a problem. I'm assuming that the error was made, missed in the (hopefully) review and caught when mother nature did her review.
And let's not put this completely on a pure calculation error. It's possible that the calculations were right and there was an error in the drawing. Of course either way, HNTB is at fault. For some reason, the step of comparing the drawings to the calculations only falls to one set of eyes.
If any of you get an resumes from HNTB with mysterious circumstances of leaving, might want to ask about this.

 

[Qshake]

JedClampett - I agree that it doesn't sound like they're just now reviewing, but I stand by my earlier note that as an industry we need to be more vigilent even as the pace of our work increases.

Another point raised is the old mantra of two sets of eyes on everything before it gets to the door. To that I would add that the extra set of eyes need to be an experienced set not just a set to perform math checks.



Regards,
Qshake

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.

 

[Debaser]

What is the procedure for approving bridge designs in the US?

In the UK we have Cat0 to Cat3 structures, where Cat0 and Cat1 require and independent check from another engineer in the Design Team, Cat 2 requires a check by a Checking Team (usually another office, i.e. geographical location, of the same company) and Cat3 requires a check by a Checking Team from a different company.

Whilst thorough, this arrangement would seem to fall foul of your requirements re engineers signing off their own designs only?

http://www.standardsforhighways.co.uk/dmrb/vol1/section1/bd205.pdf

 

[Qshake]

In the US there is no stringent system as the UK has. I have done work in the UK where I was introduced to this method. It surprised me at first but I think it a very good method.

In the US, depending who you work for, we generally have one engineer/designer do the comps and another more experienced engineer check the work. There is also a overall check that the methodology and comps are done in accordance with expecatations for the industry level of acceptance.

We are now starting to get into second designs/reviews by a separate firm or Peer reviews for structures of significance. It's coming on slowly.

If you work for the Corps of Engineers, the COE has strict rules for who can check designs and who can check drawings resulting from those designs.

I hope this provides some insight to the procedure. Please keep in mind that this may not be the case for each and every project or client. Just my experiences.

Regards,
Qshake

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