A CIVIL ENGINEER | FerrariChat

A CIVIL ENGINEER

Discussion in 'Aviation Chat' started by Bob Parks, May 16, 2021.

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  1. Bob Parks

    Bob Parks F1 Veteran
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    Nov 29, 2003
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    I have met a few that were civil but then there are some that design things that don't fly. Like that bridge in the east that has a beam failure. I'm not civil most of the time and I'm not a civil engineer or an airplane engineer but I saw the image of the beam failure and I'm convinced that it is a design flaw. The break is just outside of a gusset plate chock full of big rivets that has an abrupt ending right where the break is. From what I know about gussets and doublers , at least in airplane stuff, you do not abruptly terminate a load carrying member but you gradually disperse the loads into the adjoining structure by tapering the thickness or pattern of gusset/doublers. Curry?
     
  2. tritone

    tritone F1 Veteran
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    No problem Bob; up in Silver Art S. already fixed it.......:p
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  3. Bob Parks

    Bob Parks F1 Veteran
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    That's great! What a hoot! I hope that it is all weather tape.
     
  4. tritone

    tritone F1 Veteran
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    After a few years though, the fabric separates from the adhesive; we'll have to wait and see how long this 'fix' works.......
     
  5. tazandjan

    tazandjan Three Time F1 World Champ
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    Bad news is it stopped all the barge traffic going up the Mississippi. Cars can at least detour to the I-55 bridge, but tough for a barge. Glad I am not traveling between Albuquerque and Clarksville like I was last year. Bridge is only 48 years old, so should have been better designed.
     
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  6. jcurry

    jcurry Two Time F1 World Champ
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    nope, wasn't me.;) I'm like you, neither civil nor a civil engineer!

    re tapering the thickness or pattern of gusset/doublers, generally good design practice although most pertinent for fatigue aspects.
     
  7. Bob Parks

    Bob Parks F1 Veteran
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    I thought that there would be live loads in the structure with heavy and lighter vehicles running by. Odd that the failed beam has moved upward. Bending in the span, maybe, but it has support rods like area that failed.
     
  8. jcurry

    jcurry Two Time F1 World Champ
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    Absolutely there are varying live loads. However what were the factors of safety used in bridge design 50 yrs ago? Aircraft use FS=1.5, which if most people realized this might make them less sure about flying. I've seen numbers as high as 5-7 for bridge design, although not sure if that has changed in the last 50yrs. Use a high FS on static loads and then the fatigue stresses would likely be considered so low as to be near infinite life. Like I said, I'm not familiar with civil codes. I do know that Fatigue and Damage Tolerance analysis of airplanes has changed very significantly since 1970. Luckily the 747 was designed by a bunch of civil engineers;)
     
  9. NYC Fred

    NYC Fred F1 Veteran
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    They closed the river b/c they're worried that the bridge will fall on a barge??

    I'd be tempted to roll the dice. Supply chains are bad enough already.
     
  10. Bob Parks

    Bob Parks F1 Veteran
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    I just looked at some images from 2019 that show the crack starting in the lower part of the box beam that failed. This was missed by the inspector at that time. He has been fired. I witnessed the extreme loads on the 747 "civil" engineers and it will live with me for a long time. That was a brutal program on them and many of us.
     
  11. JJ

    JJ F1 World Champ
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    You're only wrong once.
     
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  12. vandevanterSH

    vandevanterSH Formula 3
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    "Inspector Who Twice Missed Crack in Bridge Is Fired, Arkansas Officials Say
    “the same person was the team leader in both inspections” in 2019 and 2020.

    “He didn’t see it,” Lorie Tudor, the department’s director, said at the news conference. “But the reason he didn’t see it is because he wasn’t following proper protocol.” The inspector was required to “literally go inch by inch along that beam and physically inspect every inch of the beam,” she said, adding, “That did not happen.”

    https://www.nytimes.com/2021/05/17/us/memphis-i40-bridge-crack-inspector-fired.html
     

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