Mexico Rail Bridge Collapse

Discussion in 'Physics & Math' started by RainbowSingularity, May 5, 2021.

  1. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    Dennis Tate likes this.
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    lack of suspension(shock absorbers)
    lack of flexibility
    lack of vibration monitoring
    im guessing it has all those factors involved already

    i also guess it could be something as simple as an underground subsidence
    but im looking at it
    and it is where the 2 tracks merge
    which means it would have considerably more vibration & so require a lot more advanced strengthening and shock absorption as ALL other factors would just increase vibration.
     
    Dennis Tate likes this.
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Michael 345 New year. PRESENT is 71 years old Valued Senior Member

    Messages:
    11,075
    All what you mentioned adding up to lack of maintenance

    Recently saw a American bridge due for replacement years ago according to each politician at election time

    After election - it can wait a bit longer. Bit longer it might look like Mexico bridge

    Any idea if Mexico bridge had in-built stress recorders?

    Please Register or Log in to view the hidden image!

     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    exactly what i was wondering
    specially considering it sitting right beside continental plates AND sitting below sea level on a flooding massive lake bed
    its like daring mother nature to have a go
    i will have a look back at earth quakes maybe tomorrow(if i recall)
    i doubt mexico has monitoring

    the south american exodus from covid & economic collapse will be punishing Mexico
    no one will be wanting to spend any money in the country
    and instead take as much as they can and then move north to the usa
    or extract every last dollar anyone has and not spend any of that on the local systems

    American capitalists look at Mexico and define Mexico as being the abuser who is about to cost them money so they use that ideology to refuse to invest or provide AID

    while Mexican low cost labor supports and keeps up the entire usa ecconomy
     
    Dennis Tate likes this.
  8. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    just looking at 1 picture you can see the massively wide double rail coming into a single rail
    there is almost no real support
    so its going to be a MASSIVE stress zone of torque

    Please Register or Log in to view the hidden image!

     
    Dennis Tate likes this.
  9. Michael 345 New year. PRESENT is 71 years old Valued Senior Member

    Messages:
    11,075
    Looks like an extream stress point yes

    Please Register or Log in to view the hidden image!

     
    RainbowSingularity likes this.
  10. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    i am guessing vibration from the train & from the track & from the environment
    conflicting at the ground point where road traffic & surrounding frequency comes through to a point of harmonic amplification + or -
    most likely is materials faults at moving parts
    or weak points in pour(concrete etc)
    i wonder how strict & expensive their concrete materials are
    as steel is increased to compensate for lower grad concrete, it will have an amplification process of harmonic resonance through the structure increasing weakness to various points
    assuming the weak concrete is not getting increased vibration making if fail even faster

    given the massively high volume of people
    probably nothing less than world standard top quality modern engineering would stay up for long

    built from the ground up
    including isolation & absorption with monitoring
    even so we see modern high tech expensive builds being stopped and re built or pulled down ad re formed often

    not withstanding any potential corruption concepts that may or may not exist involving short cuts and cheap materials and under budget targeting resulting in over all poorer builds etc
    maintenance issues.

    my 1st thought was terrorism
    but it appears not significant enough and the connection point and build looks like its most likely a result of over use
    expired build materials and expired design etc

    if they factor the increased traffic i wonder how the maintenance looks

    they need light rail
    electric
    whos going to pay for it ?
    usa agriculture sector would be a good start
    maybe some Californian tourism budgeting
    all together with Mexican money

    assuming they can build a defense against covid.

    i love mexican food & some aspects of their culture and the very few Mexicans i have met were very nice.
    they have such a lot of culture to offer the world and have been so ergonomically oppressed for soo long

    USA labour supply pool company(mexico) should have earnt quite a bit of money by now
    but they get trampled by the rest of south America and USA litigation toward the wall pushing back increasing costs
    wasting massive resourcing on policing a wall that doesn't really work
    that whole American bigger guns kinda attitude doesn't save money it costs money

    and Mexican infrastructure is soo terribly poor(lacking big tax incomes for proper funding)
     
    Last edited: May 6, 2021
  11. Seattle Valued Senior Member

    Messages:
    7,326
    I'm guessing inferior materials and design. This was fairly new (2012).
     
    Dennis Tate and exchemist like this.
  12. exchemist Valued Senior Member

    Messages:
    10,638
    Yes. And, this being Mexico, I would be far from surprised if corruption turns out to be at the bottom of it.
     
    Dennis Tate and Seattle like this.
  13. Beer w/Straw Transcendental Ignorance! Valued Senior Member

    Messages:
    6,097
    Was it reinforced concrete or not?
     
  14. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    thats a specialized answer depending on the type of build and what requires reinforcement.

    Please Register or Log in to view the hidden image!



    Please Register or Log in to view the hidden image!



    total guess
    over loading on a design made for very light use
    you can see a massive difference in the pillars
    and the thin section of steel truss primary fabrication struts
    using half the thickness dividing it when it probably should be double the thickness instead
    th increased flexibility of the thin pillars may have increased the movement stress on that section between the thin pillar and thick pillar

    additionally if trains are braking on that part it may be placing massive additional strain and moving the entire foundations creating sheer strain on all steel bolts
    along with increased vibration
    it would only take a small fault with the steel
    and/or the ground moving beneath one of the pillars or several of the pillars

    with the massive weight of trains sitting stopping and starting at the station it could have pulled the entire section of bridge away slightly over time

    in the last picture above
    above the lady standing
    you can se the steel is formed and split to half the width
    thats is a design fault of engineering and or a point that would have likely taken the weight and collapsed 1st as a guess from a simple glance
     
    Last edited: May 6, 2021
  15. Dennis Tate Valued Senior Member

    Messages:
    1,154
    In my wife's nation Ecuador most of the buildings in cities and towns are built to withstand earthquakes so I am guessing that that structure was not up to code.
     
  16. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    i would guess it was also above its traffic volume rating every day as a normal volume
     
  17. Michael 345 New year. PRESENT is 71 years old Valued Senior Member

    Messages:
    11,075
    RainbowSingularity likes this.
  18. hardalee Registered Senior Member

    Messages:
    384
    The Mexico bridge appears to be prestressed concrete which failed in the middle at the highest area of bending stress.

    Likely a design or construction error, no way to determine from photos shown.

    Not likely overload.
     
  19. sculptor Valued Senior Member

    Messages:
    7,891
    click on the link
    and
    what you see is called a "crack"
    ?????????????????????????
     
  20. billvon Valued Senior Member

    Messages:
    19,935
    After 9/11 everyone was an architect.
    After Malaysian Airlines flight 370 everyone was a pilot.
    After COVID-19 arrived everyone was an epidemiologist.
    Now everyone is a civil engineer.

    Such is the usual pattern online.
     
    RainbowSingularity likes this.
  21. Michael 345 New year. PRESENT is 71 years old Valued Senior Member

    Messages:
    11,075
    Looks more like broken apart

    Please Register or Log in to view the hidden image!

     
  22. sculptor Valued Senior Member

    Messages:
    7,891
    The inspector (Monty Frazier) who failed to find the crack in 2 consecutive years has been fired and may be facing federal prosecution.

    With people like him looking after our infrastructure......................................................
    (do you feel safe?)

    and
    the crack was obvious in a photo taken in 2016
    see
    https://www.commercialappeal.com/st...ando-de-soto-bridge-began-earlier/5163249001/
     
    Last edited: May 23, 2021
    RainbowSingularity likes this.
  23. RainbowSingularity Valued Senior Member

    Messages:
    6,618
    what i am guessing is
    the design & build would be for a lot less traffic than it has gotten

    aside from any design or material faults

    i expect increased traffic would exponentially increase faults

    what i am wondering is if this factor can be shown in mathematics to show a real useful benefit to learn from

    if they can see a real statistic
    then they can manage by general people counting computers so it has a system which shows its real load bearing
     

Share This Page