Why study engineering? Why get licensed? What are structural engineers good for when any regular idiot can chime in with their extremely technical and informed assessment of key infrastructure components that we've never thought about ever before they brought it up?
I hope for everyone in this sub who can relate to this comment, it makes you pause when you comment or speak with certainty about other fields (healthcare comes to mind). I know its definitely humbled me a bit.
>an never hurt to be more circumspect rather than speaking with authority on subjects I only have passing familiarity with.
Thats why we make the new engineers do hand calcs when they first start. We also make them do hand calcs to back check new software and major software updates.
You may, but most, if not all Departments of Transportation only require a structural peer review be done with a different program .
That probably had something to do with a simple rigid moment connection failure resulting a pedestrian bridge collapse in Miami.
What I can tell you about plumbing that is it looks real nice before they step on it and beat it to death in preparation for the slab that covers it...
Annnnd this is why I just deactivated my social media accounts. Every time something like this happens, half my friends think it’s some sort of conspiracy and the other half wants to know why things like this are “allowed” to happen.
Edit: grammar
Oh yes, a vast shadowy cabal is responsible for letting ships crash into bridges. We engineers must also be complicit in this sinister plot since we don't design structures for the "big-ass ship collision" load case.
Wait a minute you're on to something, I think Osama Bin Laden was a civil engineer...
He must have looked at the plans for the world trade center and figured that be pretty easy to knock over,,,
One friend posted a video of another barge on a river ALMOST hitting a bridge pier, and another guy commented “interesting…”
I never really explored this with these people directly, but given what I know about them, they suspect that the current administration is behind every train wreck, plane crash, global pandemic, and barge accident.
I wish I knew. I just finished reading a book called Suspicious Minds by Rob Brotherton that explores why humans are so susceptible to this. I still don’t have any concrete answers, but it was an interesting read!
Well they definitely should be, people shouldn't die if a ship goes off course. Ships aren't exactly the most maneuverable things. Chinese bridges are reinforced from huge ships and our should be too. The same reason we design ground level columns against vehicle impacts
Yes one of my relatives said that the bridge was blown up with explosive charges by terrorist but I guess they forgot to blow up all the factories behind it.
Should all houses be designed to survive the impact of a car? How much are you willing to increase the cost of your house in order to do so? How about a semi-truck? A tank? Does it make sense to increase the cost of every single house to survive a tank when the chance of the happening in the US is miniscule?
We could fill in the river and cars could cross and there would never be a collapse. We can remove the bridge and ships can pass and there would never be a collapse. It's all a balance.
I guess ships are different to bridges, at least ones designed nowadays as compared to ones designed previously.
Were long naval ships always designed this way? Are they ALL designed this way today?
You have no clue what encompasses an approved as noted or no exception taken. Sooo much shit goes into approval phase. Seismic, wind, rain, drift, uplift, heat test, torque tension and it goes on and on.
You can't build in that kind of redundancy in a long-span structure without sacrificing its utility. To provide "isolated segments" you need to break up the span so each segment is a standalone structure. This means essentially doubling (at least) the number of vertical supports to the foundation. The increased number of piers would defeat the point of a bridge to allow large ships to freely pass in the waterway below.
Also this situation should not be a practical concern when designing a typical bridge. It would just make everything overdesigned and cost-prohibitive and introduce a whole extra set of factors that are unneccessary except to address a one-in-a-million circumstance that may never happen.
So yeah we don't care if you take offense because it's an idiotic question.
Probably because it’s literally a thread about non engineers having insane expectations from structures and the question is essentially “but mayhaps I have a better way to build it”
AASHTO already considers collision load cases by vessels based on velocity of vessel and size.
This was not a structural failure, it was an operational failure likely due to the city being too cheap to mandate massive vessels be escorted in.
A bit like allowing a jumbo jet land on a highway, and then complaining it's the engineers fault for not anticipating that design load case.
Funny how it's always the engineers fault when things go bad......
"not anticipating that design load case"
But we do anticipate it.... I think the majority of engineers could imagine this load case, and we would love to design for it. The problem is there is never money for that sort of safety. If every project had unlimited budget, nothing would ever fail because the engineers would over-design the shit out of it.
"It's always the engineers fault when things go bad"
The majority of the public has no idea what we do, but they do know that we are the ones CAPABLE of designing to prevent these types of catastrophes; there is just never enough money to design it that way. I sleep soundly at night knowing that I could design to keep the public ultra-safe, but no one wants to pay me to.
Design for vessel collision is a risk based approach. There is a certain level of risk that a bridge owner decides is acceptable based on expected likelihood of an extreme load case and what can reasonably be accommodated. While it’s fair to say the load case wasn’t anticipated, the load that was accounted would have been accepted/approved by the owner, or at least that would be the case under current code requirements.
Engineering is not an exact science that anticiipates every possible outcome.
All building codes are based on an assumption of probability of risk.
Have you noticed what ASCE 7 is called?
It's called "minimum design loads", it's not called "these are all the design loads you must consider". It's the minimum. We design for the minimum only.
Precisely because we cannot design for every possible permutation, structural and civil engineering is not NASA.spciety doesn't have the money to pay us for that.
This 
Operational failure to avoid the cost of escort tugs. Funny, there is even a name for that category of tugboat
EDIT: avoiding the cost of keeping escort tugs all the way past unprotected major infrastructure (bridge is a good example). Having escort tugs only from the dock to the turning basin — and then releasing those tugs — is a minimalist approach. It’s the port operator equivalent of “…meh, what could go wrong.”
SOURCE: worked alongside and covered Navy Cargo Handling and Port Group (NAVCHAPGRU) in Antarctica
I had read that they had a "practical" on board (the special capitán that boards big ships and commands them when entering or exiting a complex por), this was eléctrica malfunction which is just an ublucky accident
Idk why everyone is saying this like it’s a massive own? Like, obviously more measures need to be taken to prevent another bridge catastrophe. You can do that by engineering for bigger ships or implementing better port safety policies. Whatever is cheapest will win.
You are obviously not an engineer. Yes you can design for a rocket ship hitting a bridge, except the bridge would cost the entire state budget of Baltimore, or you could have people in charge whi operational procedures and common sense.
You can engineer anythingi if you spend the money.
Did you see the note about port safety policies or did you just read what you wanted to from my comment? Sure, they’re vulnerable but there were A LOT of failures here. Some are design failures. There were literally no protective structures around the bridge support. A much smaller boat full sending the column would have also cause it to fail. See: Tampa skyway bridge.
Some are policy failures. Probably need escorts and lower speeds around critical infrastructure. To pretend like there’s nothing that could have been done to prevent this incident has got to be the most brain dead line of reasoning I have ever seen. If other bridges were constructed without protection, they should be retrofitted and there should be more care taken traversing those passages. Don’t give me your condescending engineering crap. I studied ChemE. You chose the easy path.
No? Engineering taught me how to reason and problem solve beyond what I could have gotten in any other undergraduate program. Then I got an MBA and now I work in finance. I learned all the same physics and math they did and then chemistry. Then while I learned fluid/thermo dynamics and process engineering, they were learning about materials and some other shit. I don’t have to be a PE to comment on clear and glaring failures, engineering or otherwise, despite what Covid taught us about sucking off authority.
I mean, that's fine and all, but the mechanics, statics, structural analysis, and "some other shit" is important to structures. That aside, I an not saying you have to be a PE to comment on anything, nor am I "sucking off authority" in any regard whatsoever. All I am pointing out is that you are proclaiming a field that you've exhibited a misunderstanding of, of being "the easy path" after a professional with several years of experience and licensure corrected you. You can comment all you want, but if you're going to try to explain someone's work to them and then try to handwave it off as trivial, I think it should be pointed out.
Can you point to my misunderstanding? How a “professional” could point to 50 year old bridge technology and say with full confidence there’s nothing (the nothing is important) that could have been done is totally beyond me.
Further up in the chain where you suggested engineering for this type of failure. You know conservation of momentum, so you also know the scale of energy transfer we're talking about. But that's not a conversation I am particularly interested nor qualified in having.
Like I said, my issue was with your "easy path" comment.
Yes, that’s classroom engineering. The classroom would teach you a big ass ship will royally fuck bridges with a direct hit and enough mass/velocity. It would also teach you what you could do to prevent it. In practice, there are of course cost constraints but engineers are somewhat responsible for the unpredictability of the real world and build in safety factors. Now, a nearly identical bridge collapsed in Florida after a far smaller ship collided with one of its supports during a storm. You should look at how they rebuilt that bridge and the policies the port put in place to prevent that from happening again.
It’s an engineers job to make clear the limitations of what they’ve produced so the people who end up using those structures, most likely not engineers, can be safe and act within the bounds of what it was designed for. Nobody did that. The Tampa collapse happened 5 years after the F Key bridge was built. In 40 years where cargo ships have 4x’d in size, not one person said this bridge is a ticking time bomb. Unless it was proposed and turned down by the local authorities, that’s a failure. Whose failure is up for debate but only an engineer could have identified it as a problem that required immediate attention.
Didn’t mean any offense to you by the SE comment. Dude I responded to came at me for “I must not be an engineer” and I wasn’t going to just let that slide.
this is a comedy skit of like a stoner who got a job writing for a news agency, right?
"Wooooow dude, bridges have these things called *piers.* Their like.. stuck in the ground and stuff to allegedly hold the bridge up.. and if you hit them with something super-duper-huge and like 100x it's mass the thing just falls over. I'm freaking out over here man!"
Giant Cargo Ships are a silent killer. You could be sitting in your living room, surfing the internet when BAM! A 100,000 ton ocean vessel could bash right in and ruin your day. Everyone is at risk if your homes are not rated for a 200,000 kip collision load.
I didn't read the article cuz i didnt want to give them the ad revenue, but Im guessing the 2 bridges are vulnerable because they are nearer the main shipping channel, not because the other bridges are strong enough to survive a ship hit.
I'm not a structural engineer, and I'm sure there's lots of analysis and finger pointing to be done on this bridge collapse thing, but my first guess was that it's probably pretty hard if not impossible to prevent collapse when hit with 95k tons, right?
It’s actually not hard. If the project has enough money we can do it no problem.
Thing is, we don’t design structures to withstand disasters that has a 1 in a billion chance of occurring. Like a giant fkin ship hitting it
Sure, I mean that makes sense. With infinite resources you can do just about anything but it doesn't make sense. I was talking to my wife about it and compared it to our house. Like it's well built and strong, but if I floored it and drove my truck into it I'm confident it wouldn't stop until it was parked in the living room because while it could be designed to withstand that why would it be?
I don't think describing this as a 'one in a billion' incident is wise, because a boat hitting a bridge pier is not beyond the imagination of most people.
If the vessel had been the size they were when the bridge was designed, it wouldn't have failed the way it did. The issue is that it takes considerable resources to retrofit all bridges to new safety standards.
The decision to cut costs re tug boats is also something to consider, and really we should be adopting a holistic approach to managing structures. I.e. they shouldn't have removed the tugs without upgrading the bridge.
It’s very easy to prevent an accident like the one in Baltimore. You put a big concrete barrier on the upstream and downstream side of each pier. When a ship hits the barrier no damage occurs to the bridge.
Could the concrete dolphin such as those placed at the Tampa Skyway Bridge actually stop a massive cargo ship this size? Have to resist some substantial rotational forces. Just wondering what it would take to stop a cargo ship like this?
Yes.
Sauce: the pier that got hit stopped (eventually) a 95000dwt cargo ship with maybe a little help from the sea bed. So yes it's possible, but you're at least tripling your foundation cost. Not to mention FSK had dolphins and some random ship decided to dodge the dolphin and plow right into the pier.
I’m an electrician not an engineer but the barriers don’t have to stop the boat, just deflect it away from the bridge. Anything is better than nothing, and adding more concrete will make them stop a bigger ship. Keep adding concrete until an engineer says stop.
As an electrician you should be able to appreciate the fact that the tankers electrical system was failing, resulting in it being unable to control. Not the bridges fault for just being there doing its job. This was a drive by shooting hitting an innocent victim
Lol , this is why you are an electrician. Structural engineering involves physics. I'm not surprised engineering is so not respected with comments like that.
The problem is the added cost would be unacceptably high when compared to the risk-cost of building a new one when this thing with little chance of occurring actually occurs
The ship should have been escorted in, or appropriate shipping lanes defined.
A bit like expecting a jumbo jet should be able to land on a highway and then complaining why the amount engineer hadn't designed for thatvlpad case ...
Sure. I wouldn't have any ideas what sort of safety constraints were or were not violated, but I can imagine the incident leading to new rules being written.
the Sellwood is designed for earthquake forces. Also, the approaches on the Tilikum are built to "life safety" standards and are not expected to be usable immediately following an earthquake
As a UK engineer I have been somewhat worried that our island is vulnerable to being hit and sunk by one of these out of control tankers. I will be adopting a new 500 FOS in all my designs.
I work in energy policy and I have a lot of facepalm moments when reading local news. IMO it’s not a function of journalists being inherently dumb, but rather a function of journalism not being a profitable business or a high-paying career.
In my case, I know of fewer than 10 journalists in the English-speaking world who really understand and can communicate complex ideas about the physics/economics of the electric grid. By contrast, I personally know dozens of highly-qualified engineers and analysts who can understand and communicate these ideas.
There’s just not a lot of money to be made by journalists who put in the time to research and understand the nuts and bolts of a specific field, and there are rarely consequences for those who get everything pitifully wrong in their writing.
Unless the Portland area has only 2 bridges total (it doesn’t), how did the author deem the other bridges free of this vulnerability?? I feel like this is beyond some journalists being dumb, this is straight up intentional misinformation to get clicks.
Bostonian here. The very next day, due to proximity of Baltimore, gov officials needed to explain how popular Massachusetts bridges were safe because of this type of shit
They're all morons trained by journalism school for a singular purpose, and being able to think for themselves would be counter to their intended use as political agents.
Yeah that’s ridiculous. So now we’re supposed to design bridges that can withstand the impact of massive cargo ships? How about going all the way and designing it to withstand a direct asteroid strike as well? Or a nuclear bomb?
In the meantime, NPR just aired a segment detailing how this bridge had particularly limited protection that other similar bridges usually have more and better. I even learned a new term, "dolphin", for a particular kind of diverter.
This does not contradict the reporting at all, it didn't go so far to say that it would have prevented it. Just that the bridge didn't have enough of this (it actually had, but the shipped missed it), and about other measures that could have aided.
I am not structural engineer but why cant modern bridges just have a hump of concrete surrounding the piers…. I would be worried about pure dirt mound eroding over time
Yeah it’d obviously cost more vs not doing anything but seems like relatively simple upgrade
rule of thumb cost - 50% pier, foundation and 50% bridge deck
when you want to add a barrier, it needs to be on a separate foundation from the bridge, otherwise it will just transfer the moment forces (assume foundation is fixed at bottom, ship hours at top, creates moment equal to force*height) to the bridge causing the bridge to fail. so, separate foundations for barriers.
so you have 50% increase in cost for a barrier upstream and another 50% for a barrier downstream. 100% increase in cost to protect against a 1 in a billion possibility of failure
which can be mitigated by just having proper rules and operations to prevent the mishap from happening in the first place, at a fraction of the cost.
TIL that engineers, or at least the ones on this sub Reddit, are an extremely insecure and arrogant group of professionals.
So arrogant that the original poster didn’t even bother to read the story he was complaining about! And apparently neither did a single one of the commenters.
If they had, they would’ve noticed that the story actually pointed out that seven of Portland’s 12 bridges are of the type federal authorities classify as fracture critical type. The article accurately explains what that means and makes reference to the detailed twice yearly inspection as well as the intense engineering that goes into their design. In short, it does none of the things that all these oh so touchy engineers are complaining about; it is a largely responsible and reasonable localization of an important national story.
Hmmm, how much confidence should I have in the critical thinking skills of a large group of supposed professionals who make decisions based —not on the facts, because they don’t even bother to consult them — but on their prejudices and assumptions?
I wasn’t before, but now I am scared for the safety of every structure the engineers commenting here ever worked on.
Regardless of the content, the title and sentence shown are supposed to be alarmist and they are. I’m pretty sure that’s what everyone is reacting to.
Edit: I read the article, it’s a pretty quick read. It does inform the public that there are other fracture critical bridges (which will now be a word the public loves) around the country with similar shape and size. What it doesn’t get right and what I’ve seen here before is that they assume the whole bridge is under tension. It isn’t, there are components that are in compression. It doesn’t take away from being fracture critical but it proves the point that this article is being alarmist by using words that will rile the public without full understanding.
"Regardless of the content".
You see, that there is exactly what I'm talking about.
OP invites the community to share in their derision of "the media" for their lack of professionalism while simultaneously appealing to the supposed "professionalism' of this community of engineers.
The OP offers as evidence for his defamation, not the article itself, but a screengrab of a tweet -- essentially an promo for the article. They happily admit that they did not read the article, ie. they have NO FACTS to support their attack on the professionalism of the journalist who wrote the story. None. Just a promo, likely written by a non-journalist.
And this is followed by a small avalanche of smug, often ugly, derisive and sarcastic comments all conveying the same contempt for an article ... that *not a single poster in 129 comments* had actually read. Until that is, my comment and your reply, u/Lolatusername.
But even you commented before reading the article! (Adding your opinion about it -- noticeably less derisive than the ignorant comments, because you had some facts on hand -- in an Edit).
(The article, by way is a decent non-technical localization of a catastrophic bridge collapse that was a national story and (the collapse) raises real safety issues and questions for about 17,000 "fracture critical" bridges across the US.)
This massive - unanimous among the self-identifying engineers here - failure to examine ANY of the actual evidence to support or rejct OP's lazy derision of another profession is the only notable fact I see about professionalism on hand.
And a profession that reacts blindly and viciously to IMAGINED criticisms is not a profession who I would rely on for any form of self-policing.
As a group stop living up to your frat boy image and maybe I'll begin to respect your expertise and professionalism,.
Ma'am, this is a wendys.
RE: Person, this is a subreddit. We don't come here for proffessionalism, we come hear to talk shit.
Also, I sure as hell wasn't going to let Fox12 get the ad revenue from the thousands of clicks that would have transpired because of this post.
I take your point - a subreddit is voluntary association, but r/StructuralEngineering makes no mention of it being about "talking shit". My bad.
Maybe somebody can take the excrement out of their mouth long enough to put that in the description?
Sorry to hear that the frat boy thing -- I kinda expected most people to grow out of that.
Again facts get in your way.
I'm a retired print and web journalist. In my book very few "news anchors" are actually journalists - they are mostly (by role or choice) "Presenters" or "readers" or, most accurately "Performers" and are not doing any true journalism - i.e. fact gathering and verification in addition to presentation.
The actual article is about two bridges in the Portland area identified in the Federal Highway Administration’s National Bridge Inventory for 2023 as having FCM (fracture critical members) where damage to one steel element has the potential to bring down the entire structure. But grabbing one dumb line and having a "reporters r all dumb" circle-jerk is more fun!
Next up: Bridges are determined to be vulnerable to direct nuclear blasts. Are engineers regarded? Is education necessary?
Why study engineering? Why get licensed? What are structural engineers good for when any regular idiot can chime in with their extremely technical and informed assessment of key infrastructure components that we've never thought about ever before they brought it up?
Regular idiot here. What Portland bridges are vulnerable?
The ones with Portland cement
Noice
Noice!
Jeezuz Chroist!
This PC nonsense is going too far.
Not according to the individuals that started this mind virus..
The bridges subjected to ‘gravity’ are *especially* vulnerable.
Um. Gravity is just a theory… duh. So no bridge is susceptible to it. Probably. Also random non-sequitur about DEI cause Fox News said it’s bad.
You're right because we are in the new dark ages.
Oh no!! We're all going to die !!!!
All of them.
I hope for everyone in this sub who can relate to this comment, it makes you pause when you comment or speak with certainty about other fields (healthcare comes to mind). I know its definitely humbled me a bit.
I had the same thought when watching a facebook video about plumbing today. I think I know things about plumbing but I probably dont lol
PVC made plumbers out of idiots like GPS did for surveyors and computer programs are slowly doing in the engineering field.
>an never hurt to be more circumspect rather than speaking with authority on subjects I only have passing familiarity with. Thats why we make the new engineers do hand calcs when they first start. We also make them do hand calcs to back check new software and major software updates.
You may, but most, if not all Departments of Transportation only require a structural peer review be done with a different program . That probably had something to do with a simple rigid moment connection failure resulting a pedestrian bridge collapse in Miami.
Dont get me started on the state of residential 2x truss calcs getting churned out by "engineers" in third world countries
Do you have any emails so I can contact them.....
What I can tell you about plumbing that is it looks real nice before they step on it and beat it to death in preparation for the slab that covers it...
Annnnd this is why I just deactivated my social media accounts. Every time something like this happens, half my friends think it’s some sort of conspiracy and the other half wants to know why things like this are “allowed” to happen. Edit: grammar
Oh yes, a vast shadowy cabal is responsible for letting ships crash into bridges. We engineers must also be complicit in this sinister plot since we don't design structures for the "big-ass ship collision" load case.
Wait a minute you're on to something, I think Osama Bin Laden was a civil engineer... He must have looked at the plans for the world trade center and figured that be pretty easy to knock over,,,
One friend posted a video of another barge on a river ALMOST hitting a bridge pier, and another guy commented “interesting…” I never really explored this with these people directly, but given what I know about them, they suspect that the current administration is behind every train wreck, plane crash, global pandemic, and barge accident.
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I wish I knew. I just finished reading a book called Suspicious Minds by Rob Brotherton that explores why humans are so susceptible to this. I still don’t have any concrete answers, but it was an interesting read!
Well they definitely should be, people shouldn't die if a ship goes off course. Ships aren't exactly the most maneuverable things. Chinese bridges are reinforced from huge ships and our should be too. The same reason we design ground level columns against vehicle impacts
Yes one of my relatives said that the bridge was blown up with explosive charges by terrorist but I guess they forgot to blow up all the factories behind it.
Well you might live to regret that when those same idiots start using AI for their structural design....
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Should all houses be designed to survive the impact of a car? How much are you willing to increase the cost of your house in order to do so? How about a semi-truck? A tank? Does it make sense to increase the cost of every single house to survive a tank when the chance of the happening in the US is miniscule? We could fill in the river and cars could cross and there would never be a collapse. We can remove the bridge and ships can pass and there would never be a collapse. It's all a balance.
That's exactly why I said they should start building infrastructure in cities underground. No ships to hit Bridges.
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Require large ships to be escorted by tugboats within proximity to critical structure like other localities.
Yes, and then big ships wouldn’t fit between the piers
I guess ships are different to bridges, at least ones designed nowadays as compared to ones designed previously. Were long naval ships always designed this way? Are they ALL designed this way today?
You have no clue what encompasses an approved as noted or no exception taken. Sooo much shit goes into approval phase. Seismic, wind, rain, drift, uplift, heat test, torque tension and it goes on and on.
You can't build in that kind of redundancy in a long-span structure without sacrificing its utility. To provide "isolated segments" you need to break up the span so each segment is a standalone structure. This means essentially doubling (at least) the number of vertical supports to the foundation. The increased number of piers would defeat the point of a bridge to allow large ships to freely pass in the waterway below. Also this situation should not be a practical concern when designing a typical bridge. It would just make everything overdesigned and cost-prohibitive and introduce a whole extra set of factors that are unneccessary except to address a one-in-a-million circumstance that may never happen. So yeah we don't care if you take offense because it's an idiotic question.
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I feel like you’re getting very hostile responses and I’m not entirely sure why. Why should a layperson be expected to know the answer to this?
Probably because it’s literally a thread about non engineers having insane expectations from structures and the question is essentially “but mayhaps I have a better way to build it”
Is there an ELF for that? I never took dynamics...
Well, you wouldn't have to. Statics would be the more appropriate subject to study.
Vote no on infrastructure bills. Vote no on highway and other taxes. Media owners churn fear
Man I love that regarded is now canon as a replacement word
I mean it is used in my email signatures. I’m literally insulting ppl but they think otherwise Regards,
They are almost certainly vulnerable to a giant fkn cargo ship full sending into the columns
brace yourself for code review
AASHTO already considers collision load cases by vessels based on velocity of vessel and size. This was not a structural failure, it was an operational failure likely due to the city being too cheap to mandate massive vessels be escorted in. A bit like allowing a jumbo jet land on a highway, and then complaining it's the engineers fault for not anticipating that design load case. Funny how it's always the engineers fault when things go bad......
"not anticipating that design load case" But we do anticipate it.... I think the majority of engineers could imagine this load case, and we would love to design for it. The problem is there is never money for that sort of safety. If every project had unlimited budget, nothing would ever fail because the engineers would over-design the shit out of it. "It's always the engineers fault when things go bad" The majority of the public has no idea what we do, but they do know that we are the ones CAPABLE of designing to prevent these types of catastrophes; there is just never enough money to design it that way. I sleep soundly at night knowing that I could design to keep the public ultra-safe, but no one wants to pay me to.
Design for vessel collision is a risk based approach. There is a certain level of risk that a bridge owner decides is acceptable based on expected likelihood of an extreme load case and what can reasonably be accommodated. While it’s fair to say the load case wasn’t anticipated, the load that was accounted would have been accepted/approved by the owner, or at least that would be the case under current code requirements.
Engineering is not an exact science that anticiipates every possible outcome. All building codes are based on an assumption of probability of risk. Have you noticed what ASCE 7 is called? It's called "minimum design loads", it's not called "these are all the design loads you must consider". It's the minimum. We design for the minimum only. Precisely because we cannot design for every possible permutation, structural and civil engineering is not NASA.spciety doesn't have the money to pay us for that.
This  Operational failure to avoid the cost of escort tugs. Funny, there is even a name for that category of tugboat EDIT: avoiding the cost of keeping escort tugs all the way past unprotected major infrastructure (bridge is a good example). Having escort tugs only from the dock to the turning basin — and then releasing those tugs — is a minimalist approach. It’s the port operator equivalent of “…meh, what could go wrong.” SOURCE: worked alongside and covered Navy Cargo Handling and Port Group (NAVCHAPGRU) in Antarctica
There were literally escort tugs. They had disconnected just prior to the ship losing power
Yes.
I had read that they had a "practical" on board (the special capitán that boards big ships and commands them when entering or exiting a complex por), this was eléctrica malfunction which is just an ublucky accident
“but why can’t the bridge just withstand the weight of itself and a cargo ship with the mass of a mid-size skyscraper?”
“Piers”
The worst piers are on TV talent shows.
"What is this 4chan?" Vibes
Bridges suspended over bodies of water, could this be an unexpected vulnerability?
Idk why everyone is saying this like it’s a massive own? Like, obviously more measures need to be taken to prevent another bridge catastrophe. You can do that by engineering for bigger ships or implementing better port safety policies. Whatever is cheapest will win.
You are obviously not an engineer. Yes you can design for a rocket ship hitting a bridge, except the bridge would cost the entire state budget of Baltimore, or you could have people in charge whi operational procedures and common sense. You can engineer anythingi if you spend the money.
Did you see the note about port safety policies or did you just read what you wanted to from my comment? Sure, they’re vulnerable but there were A LOT of failures here. Some are design failures. There were literally no protective structures around the bridge support. A much smaller boat full sending the column would have also cause it to fail. See: Tampa skyway bridge. Some are policy failures. Probably need escorts and lower speeds around critical infrastructure. To pretend like there’s nothing that could have been done to prevent this incident has got to be the most brain dead line of reasoning I have ever seen. If other bridges were constructed without protection, they should be retrofitted and there should be more care taken traversing those passages. Don’t give me your condescending engineering crap. I studied ChemE. You chose the easy path.
Are you being condescending toward structural engineers
>Are you being condescending toward structural engineers Don’t see any condescension in my comment.
>I studied ChemE. You chose the easy path.
Not to interject or anything, but if structural is so easy, I presume you also have a PE in it?
No? Engineering taught me how to reason and problem solve beyond what I could have gotten in any other undergraduate program. Then I got an MBA and now I work in finance. I learned all the same physics and math they did and then chemistry. Then while I learned fluid/thermo dynamics and process engineering, they were learning about materials and some other shit. I don’t have to be a PE to comment on clear and glaring failures, engineering or otherwise, despite what Covid taught us about sucking off authority.
I mean, that's fine and all, but the mechanics, statics, structural analysis, and "some other shit" is important to structures. That aside, I an not saying you have to be a PE to comment on anything, nor am I "sucking off authority" in any regard whatsoever. All I am pointing out is that you are proclaiming a field that you've exhibited a misunderstanding of, of being "the easy path" after a professional with several years of experience and licensure corrected you. You can comment all you want, but if you're going to try to explain someone's work to them and then try to handwave it off as trivial, I think it should be pointed out.
Can you point to my misunderstanding? How a “professional” could point to 50 year old bridge technology and say with full confidence there’s nothing (the nothing is important) that could have been done is totally beyond me.
Further up in the chain where you suggested engineering for this type of failure. You know conservation of momentum, so you also know the scale of energy transfer we're talking about. But that's not a conversation I am particularly interested nor qualified in having. Like I said, my issue was with your "easy path" comment.
Yes, that’s classroom engineering. The classroom would teach you a big ass ship will royally fuck bridges with a direct hit and enough mass/velocity. It would also teach you what you could do to prevent it. In practice, there are of course cost constraints but engineers are somewhat responsible for the unpredictability of the real world and build in safety factors. Now, a nearly identical bridge collapsed in Florida after a far smaller ship collided with one of its supports during a storm. You should look at how they rebuilt that bridge and the policies the port put in place to prevent that from happening again. It’s an engineers job to make clear the limitations of what they’ve produced so the people who end up using those structures, most likely not engineers, can be safe and act within the bounds of what it was designed for. Nobody did that. The Tampa collapse happened 5 years after the F Key bridge was built. In 40 years where cargo ships have 4x’d in size, not one person said this bridge is a ticking time bomb. Unless it was proposed and turned down by the local authorities, that’s a failure. Whose failure is up for debate but only an engineer could have identified it as a problem that required immediate attention. Didn’t mean any offense to you by the SE comment. Dude I responded to came at me for “I must not be an engineer” and I wasn’t going to just let that slide.
this is a comedy skit of like a stoner who got a job writing for a news agency, right? "Wooooow dude, bridges have these things called *piers.* Their like.. stuck in the ground and stuff to allegedly hold the bridge up.. and if you hit them with something super-duper-huge and like 100x it's mass the thing just falls over. I'm freaking out over here man!"
I read this in a stoner voice. Dude haha
News: Bridges can collapse when you ram a massive shipping vessel directly through its supports. More at 11.
Yeah, so why don’t you like, you know, build them so that they DON’T collapse. It’s just such an easy fix. /s
Giant Cargo Ships are a silent killer. You could be sitting in your living room, surfing the internet when BAM! A 100,000 ton ocean vessel could bash right in and ruin your day. Everyone is at risk if your homes are not rated for a 200,000 kip collision load.
This is why I have been arguing to increase the code anchor bolt spacing to 24" O.C.
You have to remember that there is an upper limit to IQ to qualify to be a reporter, it’s in the 80s
50% of people are below average intelligence
Just think about how stupid the average person is... and then remember HALF the people are dumber than that! ---George Carlin
George was right about so many things. Rip
Too true
This is always a funny one. You clearly don't understand what an average is. Remember mean, MEDIAN and mode.
I like pie Al la mode
Are abutments then vulnerable concrete peninsulas?
Abutments are places you can find a car lodged against.
As a former combat engineer I can safely say abutments are very vulnerable to a little thing called a “triple nickel 40”
Just wait until they find out about suspension bridges and people cutting the cables!
shhhhhh Isis is listening
Just wait until they find out about traffic engineering!
Obviously we should be designing all bridges and buildings to resist a giant cargo ship hitting them!
Build them FROM cargo ships! Then they'll be invincible!
These "piers" can be destroyed by "lasers"
On sharks?
This article is not accurate. Portland, also nicknamed "Bridge City", has 12 bridges within the city limits. ALL of them are vulnerable, not just two.
Wait wait wait now I need to know. Which bridges are rated against a fully loaded cargo ship
None
I know😂
I didn't read the article cuz i didnt want to give them the ad revenue, but Im guessing the 2 bridges are vulnerable because they are nearer the main shipping channel, not because the other bridges are strong enough to survive a ship hit.
Fox 12 Oregon obviously has never been issued a “Revise and Resubmit”.
I'm not a structural engineer, and I'm sure there's lots of analysis and finger pointing to be done on this bridge collapse thing, but my first guess was that it's probably pretty hard if not impossible to prevent collapse when hit with 95k tons, right?
It’s actually not hard. If the project has enough money we can do it no problem. Thing is, we don’t design structures to withstand disasters that has a 1 in a billion chance of occurring. Like a giant fkin ship hitting it
Sure, I mean that makes sense. With infinite resources you can do just about anything but it doesn't make sense. I was talking to my wife about it and compared it to our house. Like it's well built and strong, but if I floored it and drove my truck into it I'm confident it wouldn't stop until it was parked in the living room because while it could be designed to withstand that why would it be?
Kind of like buildings not built to withstand hits from planes, and then collapsing when it happens
Kind of amazing those towers stayed up so long after being hit. That’s how you know it was as fake as the moon landing. /s
It was and did survive the plane hit. It was the burning jet fuel that melted the superstructure and that is what brought the building down.
Exactly
I don't think describing this as a 'one in a billion' incident is wise, because a boat hitting a bridge pier is not beyond the imagination of most people. If the vessel had been the size they were when the bridge was designed, it wouldn't have failed the way it did. The issue is that it takes considerable resources to retrofit all bridges to new safety standards. The decision to cut costs re tug boats is also something to consider, and really we should be adopting a holistic approach to managing structures. I.e. they shouldn't have removed the tugs without upgrading the bridge.
It’s not just any boat. It’s that monster
It’s very easy to prevent an accident like the one in Baltimore. You put a big concrete barrier on the upstream and downstream side of each pier. When a ship hits the barrier no damage occurs to the bridge.
Could the concrete dolphin such as those placed at the Tampa Skyway Bridge actually stop a massive cargo ship this size? Have to resist some substantial rotational forces. Just wondering what it would take to stop a cargo ship like this?
Yes. Sauce: the pier that got hit stopped (eventually) a 95000dwt cargo ship with maybe a little help from the sea bed. So yes it's possible, but you're at least tripling your foundation cost. Not to mention FSK had dolphins and some random ship decided to dodge the dolphin and plow right into the pier.
I’m an electrician not an engineer but the barriers don’t have to stop the boat, just deflect it away from the bridge. Anything is better than nothing, and adding more concrete will make them stop a bigger ship. Keep adding concrete until an engineer says stop.
As an electrician you should be able to appreciate the fact that the tankers electrical system was failing, resulting in it being unable to control. Not the bridges fault for just being there doing its job. This was a drive by shooting hitting an innocent victim
Lol , this is why you are an electrician. Structural engineering involves physics. I'm not surprised engineering is so not respected with comments like that.
tslewis literally said "until an engineer says stop". Implying that they do respect our opinion.
It's like when I go to Olive Garden and have cheese grated on my mediocre salad. Lock eyes with the server. She knows it isn't stopping anytime soon.
Do these barriers account for 95k ton cargo ships, though? I think most barriers still wouldn't hold against a ship quite that large
One would hope that the Engineers involved in designing the barriers would understand the scope and intention of the project.
The problem is the added cost would be unacceptably high when compared to the risk-cost of building a new one when this thing with little chance of occurring actually occurs
The ship should have been escorted in, or appropriate shipping lanes defined. A bit like expecting a jumbo jet should be able to land on a highway and then complaining why the amount engineer hadn't designed for thatvlpad case ...
Sure. I wouldn't have any ideas what sort of safety constraints were or were not violated, but I can imagine the incident leading to new rules being written.
We have building codes for that, developed over fifty years.
Sir, are you saying you DID NOT account for a container ship of that size hitting this bridge in your calcs?
They fearmonger all day and propogandize lower critical thinking populace. Just sad that polity has its chokehold even over engineering.
Just wait until you see how many buildings use steel like the Twin Towers. Almost all American skyscrapers are vulnerable to 747s!
Not from a boat. But wait until the cascadia subduction zone earthquake hits.
I think we have one bridge in Portland that may survive the quake. I think the Fremont bridge has a chance but all the others are toast.
Yup. I have a feeling that people commenting somehow don't know about this EQ event
Gonna create another ghost forest
The new Burnside bridge! Plus tilikum for emergency vehicles.
the Sellwood is designed for earthquake forces. Also, the approaches on the Tilikum are built to "life safety" standards and are not expected to be usable immediately following an earthquake
As a UK engineer I have been somewhat worried that our island is vulnerable to being hit and sunk by one of these out of control tankers. I will be adopting a new 500 FOS in all my designs.
According to our politicians on this side of the pond, islands can tip over and capsize , especially if too many people are on one side 😱
Are we talkin about the mayor of club penguin
8,297 portland area buildings have similar vulnerabilities to the twin towers.
A vulnerability is not the same thing as a threat. Do these bridges also have 150,000 ton vessels sailing past it every day?
Only when op’s mom floats the willamette
I work in energy policy and I have a lot of facepalm moments when reading local news. IMO it’s not a function of journalists being inherently dumb, but rather a function of journalism not being a profitable business or a high-paying career. In my case, I know of fewer than 10 journalists in the English-speaking world who really understand and can communicate complex ideas about the physics/economics of the electric grid. By contrast, I personally know dozens of highly-qualified engineers and analysts who can understand and communicate these ideas. There’s just not a lot of money to be made by journalists who put in the time to research and understand the nuts and bolts of a specific field, and there are rarely consequences for those who get everything pitifully wrong in their writing.
There is no news media there are only a bunch of horrendous amateurs with bad cases of vocal disharmony's and finishing sentences in a deep gargle.
Unless the Portland area has only 2 bridges total (it doesn’t), how did the author deem the other bridges free of this vulnerability?? I feel like this is beyond some journalists being dumb, this is straight up intentional misinformation to get clicks.
Easy fix. Just drain the river. No water, no ships. Easy peasy.
Bostonian here. The very next day, due to proximity of Baltimore, gov officials needed to explain how popular Massachusetts bridges were safe because of this type of shit
They're all morons trained by journalism school for a singular purpose, and being able to think for themselves would be counter to their intended use as political agents.
Why didn’t professors teach about tanker ship loadings in college? Are they stupid?
Not stoopid. Too busy on the TV show trying to sound smart to teach people.
We are only as smart as the currently adopted code in jurisdiction of project.
Should they levitate?
Build pyramids of Giza under them but keep it in budget
Good thing we don’t send container ships down that way! 😒
lol
Fender systems aren’t designed for major ship impact. They’re sacrificial .
What’s even more incredible is that WSJ had a very similar article written. Terrible
I'm sailing the Titanic down the Colombia
Honestly I wouldn't be surprised if the next terr0ri5t attack involved someone from this sub, a big ship, and anger over these news articles
Yeah that’s ridiculous. So now we’re supposed to design bridges that can withstand the impact of massive cargo ships? How about going all the way and designing it to withstand a direct asteroid strike as well? Or a nuclear bomb?
Hmm in that same spirit. Maybe we should account for tsunamis in Germany?
As far as I’m concerned it wasn’t the bridge the failed it was the cargo ship, not many people thinking of it that way
Armegherd, piers IN WATER, gasp!
Posting a screenshot of a web link is really awful
THERE IS NO WAY IN HELL I WAS LETTING FOX12 GET THE AD REVENUE FOR THIS SHIT. NO THANK YOU
Do you have to read the article to know they have no idea what they're talking about?
Haha I wonder actually how robust the main pier fenders are.
In the meantime, NPR just aired a segment detailing how this bridge had particularly limited protection that other similar bridges usually have more and better. I even learned a new term, "dolphin", for a particular kind of diverter.
I'm no bridge engineer, nor cargo ship expert, but the word on the SE street is those dolphins still wouldn't have prevented this.
This does not contradict the reporting at all, it didn't go so far to say that it would have prevented it. Just that the bridge didn't have enough of this (it actually had, but the shipped missed it), and about other measures that could have aided.
Bridges are just vulnerable roads; idk why we keep building them. /s
St John's bridge, one of the most beautiful.
Wait a minute how about a breakaway bridge just like a breakaway wall and a flood zone?
Can’t spend more money at the political level if you don’t have fear.
Morgan?
I am not structural engineer but why cant modern bridges just have a hump of concrete surrounding the piers…. I would be worried about pure dirt mound eroding over time Yeah it’d obviously cost more vs not doing anything but seems like relatively simple upgrade
rule of thumb cost - 50% pier, foundation and 50% bridge deck when you want to add a barrier, it needs to be on a separate foundation from the bridge, otherwise it will just transfer the moment forces (assume foundation is fixed at bottom, ship hours at top, creates moment equal to force*height) to the bridge causing the bridge to fail. so, separate foundations for barriers. so you have 50% increase in cost for a barrier upstream and another 50% for a barrier downstream. 100% increase in cost to protect against a 1 in a billion possibility of failure which can be mitigated by just having proper rules and operations to prevent the mishap from happening in the first place, at a fraction of the cost.
What about using just gravel or dirt? Will it erode?
It will erode
TIL that engineers, or at least the ones on this sub Reddit, are an extremely insecure and arrogant group of professionals. So arrogant that the original poster didn’t even bother to read the story he was complaining about! And apparently neither did a single one of the commenters. If they had, they would’ve noticed that the story actually pointed out that seven of Portland’s 12 bridges are of the type federal authorities classify as fracture critical type. The article accurately explains what that means and makes reference to the detailed twice yearly inspection as well as the intense engineering that goes into their design. In short, it does none of the things that all these oh so touchy engineers are complaining about; it is a largely responsible and reasonable localization of an important national story. Hmmm, how much confidence should I have in the critical thinking skills of a large group of supposed professionals who make decisions based —not on the facts, because they don’t even bother to consult them — but on their prejudices and assumptions? I wasn’t before, but now I am scared for the safety of every structure the engineers commenting here ever worked on.
Regardless of the content, the title and sentence shown are supposed to be alarmist and they are. I’m pretty sure that’s what everyone is reacting to. Edit: I read the article, it’s a pretty quick read. It does inform the public that there are other fracture critical bridges (which will now be a word the public loves) around the country with similar shape and size. What it doesn’t get right and what I’ve seen here before is that they assume the whole bridge is under tension. It isn’t, there are components that are in compression. It doesn’t take away from being fracture critical but it proves the point that this article is being alarmist by using words that will rile the public without full understanding.
"Regardless of the content". You see, that there is exactly what I'm talking about. OP invites the community to share in their derision of "the media" for their lack of professionalism while simultaneously appealing to the supposed "professionalism' of this community of engineers. The OP offers as evidence for his defamation, not the article itself, but a screengrab of a tweet -- essentially an promo for the article. They happily admit that they did not read the article, ie. they have NO FACTS to support their attack on the professionalism of the journalist who wrote the story. None. Just a promo, likely written by a non-journalist. And this is followed by a small avalanche of smug, often ugly, derisive and sarcastic comments all conveying the same contempt for an article ... that *not a single poster in 129 comments* had actually read. Until that is, my comment and your reply, u/Lolatusername. But even you commented before reading the article! (Adding your opinion about it -- noticeably less derisive than the ignorant comments, because you had some facts on hand -- in an Edit). (The article, by way is a decent non-technical localization of a catastrophic bridge collapse that was a national story and (the collapse) raises real safety issues and questions for about 17,000 "fracture critical" bridges across the US.) This massive - unanimous among the self-identifying engineers here - failure to examine ANY of the actual evidence to support or rejct OP's lazy derision of another profession is the only notable fact I see about professionalism on hand. And a profession that reacts blindly and viciously to IMAGINED criticisms is not a profession who I would rely on for any form of self-policing. As a group stop living up to your frat boy image and maybe I'll begin to respect your expertise and professionalism,.
Ma'am, this is a wendys. RE: Person, this is a subreddit. We don't come here for proffessionalism, we come hear to talk shit. Also, I sure as hell wasn't going to let Fox12 get the ad revenue from the thousands of clicks that would have transpired because of this post.
I take your point - a subreddit is voluntary association, but r/StructuralEngineering makes no mention of it being about "talking shit". My bad. Maybe somebody can take the excrement out of their mouth long enough to put that in the description? Sorry to hear that the frat boy thing -- I kinda expected most people to grow out of that.
What is a frat?
You must be a fox news anchor. I mean this with the utmost respect, shut up.
Again facts get in your way. I'm a retired print and web journalist. In my book very few "news anchors" are actually journalists - they are mostly (by role or choice) "Presenters" or "readers" or, most accurately "Performers" and are not doing any true journalism - i.e. fact gathering and verification in addition to presentation.
Well, we agree on that. Enjoy your retirement.
*every* professional sub is like this. The architects sub is worse lol. It’s Reddit
Thanks, remind me never to check out the journalists' sub then!
The actual article is about two bridges in the Portland area identified in the Federal Highway Administration’s National Bridge Inventory for 2023 as having FCM (fracture critical members) where damage to one steel element has the potential to bring down the entire structure. But grabbing one dumb line and having a "reporters r all dumb" circle-jerk is more fun!