Well There's Your Problem | Episode 36: I-35W Mississippi River Bridge Collapse 

I think it's telling on how freakin' BORING your "teaching" of bridge physics is that I fell asleep not once, but twice, trying to listen to it. YAWN.

You know, when listening to the start of this episode I realized that a lot of times in SimCity 2000 I'd build up a city as sensibly as a kid can manage, unlock freeways, and then puzzle over how the hell I was supposed to add one to my downtown without bulldozing about a hundred core city lots, and only now does it dawn on me that I was essentially roleplaying the leadup to some of the greatest crimes in urban design of the mid-twentieth century. Also props to Alice for the Owl City reference.

the genuine but subtle (and possibly sinister?) excitement in Roz's voice when he gets to talk about beam theory is actually extremely heartwarming

I love listening to this 65 year old man and his cool young friends.

Well There's Your Problem's Image of Utopia: No cars, lots of trains, some horses No language, because it was a mistake All medical and engineering professions are fully interdisciplinary Humans can never cross rivers via bridge (crossing via other means is not strictly prohibited but meet with harsh scrutiny) Every human being has a personal union to represent themselves Drinking, smoking and switchblade possession is mandatory on every job site All booze will have small amounts of Anti-Freeze additive

Justin: Then the bridge fell into the water and everyone on it died. Alice: That's so sad hang on I have a meme for that

This may seem funny, but in reality bridges only act like this when they are EXTREMELY UPSET.

As a non-destructive technician, the quote "...people will pay to get the inspections done that they need to get done, and they'll get the report back that says 'all of these critical issues need to be addressed immediately,' and then they'll just file it away..." rings so true I now tinnitus.

As a big fan of math I really appreciate all the effort Roz puts in to try and explain mathematics. As a fan of comedy I really appreciate the amount of shit he gets. Pls more calculus in podcasts

Me: Mom can we have tacoma narrows bridge disaster? Mom: We have tacoma narrows bridge disaster at home. Tacoma Narrows bridge disaster at home:

I cannot express how much I love when this podcast gets into more technical details.

The main purpose of a hard hat on a construction site is so there's enough left of your head that your next-of-kin can identify your corpse. This is important, otherwise the company won't know it was you, you might have just wandered off, who knows? and then the insurance company would refuse to pay off your next-of-kin. You mentioned the ball-whacking property of a safety harness. As Justin says, "Yes." The very first time I ever put on a harness was for a construction job involving installing four water pumps in 45 foot deep, 8 foot diameter metal cans. The cans had to be pretty close to perfectly plumb, as the pumps where hanging from the top. However, apparently something went wrong with the soil testing, and they had missed a vein of clay underground. Clay has an ultimate weight holding capacity of zero, that is, if you put any weight on it at all, eventually the weight will sink into the clay. So the cans were slowly sinking, not all that much of a problem, but they were leaning as well. It was my job to measure the out-of-plumbness of them. The technique was, I got a 12 foot 2x4 and fifty-foot reel of string and hung my 32 ounce plumb bob down the shaft from the 2x4 across the top of the can. Since it was underground and out of the wind, the plumb bob hung almost perfectly vertically. With a box tape I measured the distance from the plumb bob string to the inside face of the can at the top, then I was to get lowered into the can to measure it again near the bottom. The guys up to would then rotate the 2x4 45° and I'd measure the distance at the top and bottom again, enabling me to measure the plumbness at eight points around the can. They brought out this harness and a tripod with a reel with a steel cable on it. I put on the harness and slipped over the edge, and they began lowering me down the hole. Unfortunately whoever had wound up the cable on the reel last time didn't do it with tension on the cable, so it was loose. I got down about five feet, and then the cable slipped and unwound and I suddenly free-fell about maybe six feet before it took up the slack. As you noted, I absorbed all the impact with my crotch, which was a literally breathtaking experience. That was the first of thirty-two trips down and up the cans I got to do that day. I have other horror stories about clay too. I surveyed excavations for a seventy-foot high berm around a water reservoir about a mile E/W and a mile and a half N/S. You'd be walking along on apparently solid ground, and then suddenly sploot! you're waist-deep and sinking. That clay nearly dragged me under more than once. That God damned site was the mother of all OSHA violations. I was out there six days a week for about a year, and that was the most dangerous job site I ever worked on in forty years of land surveying, including surveying in moccasin-infested swamps, wading chest-deep through ponds full of alligators, and hundreds of hours running a transit set up in the intersections of busy roads with nothing but a few cones between me and the 70 MPH traffic. It was the only job site I ever worked on where somebody got killed on the job while I and my crew were on site.

This was a particularly good episode. Alice’s “A MAN HAS FALLEN INTO THE RIVER” drop killed me.

I really appreciated being able to exorcise my statics demons watching this. Hearing a civil/structural engineer say that the bending moment diagram is unintuitive/upside-down thrilled me to no end. I was also as incredulous as Alice and Liam upon learning that the unit of measurement of the "area moment of inertia" is a quartic distance. (wtf?). I don't know if Justin fucked it up or its a colloquial thing, but the degree to which a cross section resists bending in certain directions has more than one name. It is called both "The second moment of area" AND "The area moment of inertia" (among others). To make this EVEN MORE confusing, the "moment of inertia" is used to refer to an object's resistance to being rotated around specific axes. The moment of inertia is also called the "mass moment of inertia", "angular mass", or the "rotational inertia". This second term is NOT a term from statics (things that don't move), but from dynamics (things that DO move). If you know of Newton's second law of motion (F=m*a), it is basically the angular version of that (M=I*alpha I think). Thank you for allowing me to vent, and if you are currently studying this, I am very sorry.

Sleeping status: woke. Sipping on: coke. Mississippi bridge: broke. Yep, it's podcast time.

To those of you wondering why this isn't the video you were expecting: There have been others before you. You are among the unfortunate few who have been slipping between timelines. Our universe isn't scheduled to get the Tacoma Narrows episode until _next_ week. With any luck, you'll remain spatiotemporally stable until then. But if you don't get the right episode, you'll know you've slid again. If I'm the first to tell you, I'm sorry you had to hear it this way and I hope you find your way back home. Good luck and Godspeed traveler!

If there is one thing I have learned is that fixed connections are bad, and roller connections are good. In lay terms, bridges should be massive skateboards made exclusively out of smaller skateboards. Skateboards all the way down. Instead of the slump test we do the kickflip test.

This entire podcast has the same energy as a frustrated old college professor telling his confused research intern: *Well there's your problem!*

So I studied structural engineering at the University of Minnesota, and the bridge collapsed 1 week before I moved in for my freshman year. Suffice it to say, the 35W bridge was a major point of reference throughout my college education. Also, welcome to civil engineering: where everything we know we learned from horrific, mass casualty causing failures. :) Edit: since you brought up the light rail, by way of context, it's worth noting that there were 2 proposed light rail routes, and the one that would have involved 35W was objectively worse. It was proposed primarily as a way to bypass the UMN campus, as the school was digging in their heels over concerns that it might affect their nanotechnology research labs. Ultimately, though, those concerns were addressed, the U relented, and we got a light rail built through campus and beyond, making the 35W bypass redundant.

Email didn't work Hands-down my worst working conditions were at a Regal Cinemas in Foothill Ranch, CA for half of 2005. I don't even know where to begin, but here's some highlights: 1. Rodent problem It was so bad that one time a patron's toe was bitten by a rat while watching a movie wearing open toed shoes, the managers actually paid him off in gift certificates somehow. One time a rat died in the wall between two theaters causing the most wretched smell ever, and so the managers decided instead of losing revenue by closing those two theaters down just screened the least popular movies there. If a patron complained they'd just get a refund, but the majority of the time people would actually endure the conditions and sit there for a full 90+ minutes. I worked as an usher and had to clean those theaters after screenings and I'd pull my shirt over my nose and hold my breath as long as possible, the smell got worse and worse to the point where that entire wing of the building was uninhabitable to anyone with a sense of smell. Another time the trash compactor broke, so we had to pile all the trash bags up behind the building for 3 days until the compactor was fixed. Once that happened, I was left with the responsibility of relocating this gargantuan pile of trash bags back into the building and put into the compactor. In those few days a giant nest of rats, what could be reasonably described as a "hive" over the course of an hour would one by one sprint out from this pile between my legs, over my feet, onto my hands, fleeing from the destruction of their rat kingdom. 2. Changing light bulbs The ushers there liked to perform "earthquake drills" while changing light bulbs. The 6-foot A-frame ladder provided for changing hallway light bulbs was too short, so even the tallest employee would have to stand on the top step of the ladder, and while doing so, the usher charged with holding the ladder would often times start shaking it while yelling "earthquake! earthquake!" and somehow no one was ever injured doing this. I chock it up to all of us being socal natives that regularly skateboard and surf. There was a dinky cherrypicker used for changing the light bulbs in the lobby, which the ceiling was probably 60 feet high. The cherrypicker at one point might have had a functional leveling system, but during my tenure it did not function properly, and once it got about halfway up it would sway in every direction like an Atari 2600 joystick during an intense game of Galaga. You felt safer with the stoned usher performing the aforementioned "earthquake drill" on the wooden A-frame ladder. 3. Concessions Nearly everyone working in this theater was a teenager from the suburbs, zero personal responsibility, zero common sense, only there because their parents bought them a WRX for their 16th birthday under the condition they get a job. The people in concessions were hands down the least responsible, the ice machines were in a hallway the ushers and projectionists constantly used, which is also where the timeclock and break room were. The people in concessions would recklessly spill ice all over the place, causing slip and falls on a daily basis, once again I don't know how a serious injury never occurred during my tenure. The least dangerous, but still gross condition that I found out about years later, is the concession workers NEVER cleaned the nozzles for the soda fountains, which prevents mold from growing in them. One told me about it years later thinking it was hilarious, and upon me explaining both him and I and all the other employees drank soda from those fountains he exclaimed "oh, I never thought of that..." 4. Sanitation The theater had a cleaning crew that came in after hours, but ushers were responsible for keeping everything clean during business hours, including bathrooms. Drunk people would miss the toilet while vomiting, children and special needs persons would have accidents, "service animals" (i.e. asshole with patches sewn on their dog's harness to bring them everywhere) would urinate and defecate on the floors. The theater provided ushers with that sawdust stuff, generic Folex, and generic glass cleaner for cleaning this stuff. That means if there's a pile of shit on the ground, I'm picking it up with paper towels, if someone vomits on a tile floor I'm using sawdust and sweeping the vomit sawdust clumps up with my broom and porter. You'd think at the very least we'd have been provided with latex gloves, but apparently that was too much. All the above issues, and plenty of others were constantly pointed out by myself and my coworkers to the GM at the time, whose name was Mark Krebs, and every time he just said "I'll talk to corporate." The whole experience definitely made me never want to set foot in a movie theater ever again.

Hey what gives, this isn't the bridge disaster I was promised last episode. Or the last 35 now that I think about it.

"Make it thicker. It doesn't matter how much it weighs, just make it thicker." And now you all are putting me to mind of a bridge designed by cosmologists. Where real statistics don't matter and everything is Fermi estimated to the next power of ten. And the end result is that the whole bridge is just "big chungus."

Ain't gonna lie, I understood a lot more of Justin's beam theory lecture than Liam's rant about sportsball...

Justin: "Let me know in the comments if you're confused by this." Me, looking at the diagram of the bridge covered in random red squiggles: "No this makes perfect sense."

Ah, talking about drilling holes to relieve stress reminds me of a gun story. When Colt decided to make a 10mm version of the classic M1911 design, they discovered that the frames kept cracking in one specific place. After some experimentation, they solved the problem by simply cutting that section of frame away. It sounds wildly stupid and counter-intuitive, but it worked.

A SCHOOLBUS HAS FALLEN INTO THE RIVER IN LEGO CITY!

Justin when Alice says things normally: "Yes..." Justin when Alice says bridges need to be more rigid: "Nooooooooo!"

>Euler >Justin pronounces it you-ler >it's actually pronounced oil-ler (I am math major btw) >Alice didn't chime in My disappointment is immeasurable and my day is ruined.

* goes to comment "p is stored in the beams" * alice says it right as I start typing * is sad

I have so many god damn unsafe stories from my 9-month stint in railroad engineering management that I don't even know where to start honestly.

Note older style concrete arch bridge in background, which has not fallen down, in spite of being older than the collapsed bridge, and may out live the new bridge as well.

Perfect timing. Just the thing I needed to get through overtime. One thing I heard about this disaster is that a lot of corrosion on the bridge was caused by decades of bird shit building up on the members and hardly ever being cleaned. The bird shit reacted with the steel promoted rust. Some birds were apparently even nesting and crapping inside the box girders. Not a good thing for a bridge that was only half engineered and not being repaired.

1:20:30 The rage that washed over me at hearing the words "... we need a 10 lane highway" 💀💀💀

Oh yeah I remember this disaster, it was the the first time we visited the US. And I was so surprised that a bridge could just collapse in the richest country on earth, then I learned that US infrastructure is basically at Bulgaria level. A few prestige projects a whole lot of crumbling, rustling shit

I was midway through sewing a facemask on a sewing machine when I heard "I'm Justin Roczniak and my pronouns are Justin Roczniak" and the resulting snort laugh meant I almost sewed my thumb to the mask.

I think this is a great example of an episode that does a great job of differentiating WTYP as both (1) a podcast that contains actual engineering and (2) a podcast that is funny. I cannot wait for the eventual multi-parter that opens each section with the different engineering challenges & failures, creating a sense of mounting comic horror for Alice to continuously stay one step ahead of the audience in discovering. ("The Demon Core" might work for something like that, if you pepper in other WWII research accidents, since explaining how the experiment works highlights how crazy/Chad Slotin is.)

Justin: Let's start by getting an idea of how this bridge works, right? Let's go to the NTSB report. Alice: Well, okay, it holds up a thing and then, like, people drive over the top of it, is my understanding. I've played Poly Bridge! Justin: Yes! Liam: *snorts* Me: I love these idiots.

YESS. This is such an incredible example on the topic regarding American infrastructure. So glad you guys looked at this. Would something like the 2006 Ivory Coast toxic waste dump be something to look at next?

“Ah it’s probably fine” is the sentence that transforms an engineering project into a WTYP episode

I now know why the US gets a grade of D in infrastructure, Mechanics is hard enough in metric but if you're gonna do it in imperial then there is no hope.

51:25 For an experiment I was working on, we had a whole bunch of incredibly thin (this was a requirement) flexible circuits printed. The lowest bidder company that made them was too cheap to cut them out with something like a water jet or laser, or even a router. They had someone cut them out by hand with scissors, creating a bunch of little tiny rips. These rips grew and grew, until they threatened to break the circuit traces. Fortunately, a very experienced mechanical engineer remembered the technique you describe, and we were able to save the circuits with a very sharp hole punch.

Because I feel like it didn't get enough of a laugh: Alice, I liked your apartheid emeralds joke.

Negative zero can be avoided if you make the numbering go from 14 to -14, putting 0 in the middle.

I think this is one of the best episodes you guys have done in awhile. It's educational, comparatively focused, and the humor doesn't feel like it's derailing Justin's engineering talk but adds to it by voicing the realities of how so much of this is counter intuitive, and leading him to explain why the counter intuitive thing is correct. Its really the kind of episode that reminds me why I like this show, and why I put up with the more unfocused and all over the place episodes.

The real disaster is using non-SI units for force calculations.

Comrade is the perfect universal pronoun. All other pronouns are outmoded.

i was just about to go to sleep, then i saw a new episode was up

Justin's "...NO." at 40:06 gave me gallons of life force, thank you

"And in the year 2045, Well There's Your Problem signed off with a podcast recorded from a bridge at risk of collapse. Special guest: Mothman."

When I worked as a dishwasher for Bento, they used the space on top of the walk ins as extra storage. Whenever there was a delivery, I would be trapped into a corner between the machine and the freezer, and people would begin throwing these 40+ pound boxes up on top of the freezer. It was bad enough when I had to climb on top of the slippery, polished steel top of the freezer, but every time they did this I was at least almost hit if they missed their throw, because it would come flying down on top of me. I got hit a few times. I couldn't get them to not do this, and I got in trouble for leaving my post when there was a delivery, because I had to help unload deliveries whilst being the only dishwasher and rice prep. There was a strong smell of gas coming from the rice cooker, and when I brought it up the managers said "I thought I smelled something... we'll take a look at it." They never took a look at it, and I and others would still get lightheaded when standing too close to it. I was not trained in any food safe procedures, at all. This was whatever, except it meant that EVERY SINGLE TIME the food safety inspector inspected, the office management would demand that I hide out of sight while he inspected. The kitchen crew was not informed that I was not allowed to be in the kitchen--or visible--during inspections, and they constantly yelled at me when it happened because there would be a massive pile up of dishes because, again, I was the only dishwasher in a busy restaurant. The worst part was that corporate demanded that they have "practice" inspections bi monthly, and the inspector showed up during the lunch rush everytime.

Structural engineering: what happens when your math nerds learn to drink with the iron workers.

I appreciate how Justin states the exact reason that people live in Wyoming and reaches the wrong conclusion. There is indeed nothing in Wyoming, but that is the appeal of the state. Idk why so many millionaires move to the state, its probably for tax reasons.

I wonder if the three of you have ever seen the german short film "Staplerfahrer Klaus - Der Erste Arbeitstag" (Forklift Driver Klaus - First day of work). If you have not, I would love for the three of you to watch it sight unseen and record the reaction.

wouldn't it be funny if justin in post post production interrupted justin in post production to correct justin in post production worrying about hearing the AC over the mic

Glad to see the return of our friend p of ‘p on nut’ fame

my brain goes smooth when the math happens, but i do appreciate that roz's explanation of bridge construction and trusses made me think back to previous bridge episodes and gave me enough context to go "ah yes i understand" when i do not actually understand.

56:11 A coal barron in Southern Illinois back in the early 1900's actually had concrete mixed with champagne when constructing a mine just to show his wealth.

I'm excited to listen to this at work tomorrow. I love the thrill of this content, while working for The Man.

some fun tidbits from URS corp's wikipedia page: "In August 2011, a near criticality incident happened with eight rods of plutonium placed close to each other to take a photo." "This occurred during lax safety protocols and after they replaced all of the members of criticality safety team with URS employees." also according to the area 51 wikipedia page they may employ the guards

Fun Story: My Cousin worked in Security at the University of Minnesota at the time and had good time yelling at reporters and other gawkers.

Nobody calls it I-35 "West". It's "thirty five double-you" (Like its twin, thirty five eeeeeeeeeee)

Like others have said, it's just "eye thirty-five double-u", not "west." Also, I figure it's worth mentioning the near-disaster that happened on the new bridge the weekend after George Floyd was killed, where an oil tanker semi truck barrelled into a crowd of protesters on May 31, 2020. Pretty miraculous that nobody was killed there (I was especially worried people might have gone over the edge, especially since the new bridge is actually a pair of parallel structures with a sizable gap between them...)

"Let's get an idea of how this bridge works." Really well until not at all.

As someone who’s lived in Minneapolis my whole life, it’s wild to hear people that aren’t from like Wisconsin making jokes about us that aren’t just generic to the entire state if not the entire midwest.

“We don’t need safeties where we’re going” - oldmananderson

Minneapolis local here: I can tell you this was all that was talked about for what was probably months but felt like years. :O

The week the Philadelphia Eagles fans were in Minneapolis for the super bowl was probably the most scared I've been for my life here before mpd started tear gassing the shit out of us.

Oh I can't wait to listen to this I actually lived through this one. And by lived through I mean mildly inconvenienced due to traffic as I wasn't on the bridge or something. I'm still pretty sure that Dems took the governors office in 2010 (even though it wasn't against pawlenty -- and this was probably the reason he didn't run for a 3rd term) because of this. Pawpaw had done some serious defunding of roads right before this and that went over like a lead balloon for obvious reasons.

Pennsylvania and New Jersey engineering disasters you should do are Action Park, Centralia, and the Rhodes Opera House Fire

learning statics from engineering course: broke. learning statiscs from some podcast: woke

I’ve never used Twitter, and never will, and looking in from the outside it confounds me (especially in recent years): I’ve never, ever heard anyone say anything good or positive about it. It just seems to make everyone miserable and insane, and constantly complain about it. You know, you can *Just. Log. Off.* It’s easy, and painless, and good for you. I do understand that the process of “getting Likes” effectively short-circuits your dopamine delivery system... but if you’re afraid of missing out on that, another option is to just jam your mouth full of Skittles and chew it down to bolus - it literally feels the exact same. :D

Can't wait for a "The gang tries to build a bridge" bonus episode

First it was groverhaus, now it's groverspan, what's next...groverstadium?

Justin Rozniack's name is Justin Rozniack, and Justin Rozniack's pronouns are Justin Rozniack

Any Austin resident could have told you that nothing good ever came from I-35

You should cover the disaster that was the planning and building of I-35E through Saint Paul. It's an interesting example of how Interstate planning in the 60s had some... issues.

We need a tshirt with Alice's "Just make it more rigid!" tagline lol

I am a Minnesotan who lives in the suburbs of the twin cities and I remember very vividly when this disaster happened. It also led to my hometown's own, much smaller obviously, bridge over the Mississippi being replaced.

I remember seeing the squished rail car stuck under the bridge from the U of Minnesota campus at lunch during a baseball camp. Someone at the camp had been on the bridge just before it collapsed. I was on the bridge the day before Also. the Red Bulls also had the longest tour our of any group in Iraq. Their tour was extended to 20 months Also, also, the failed gusset plate is now a statue in front of the University of MN engineering building. The east side gusset plate and beams have been at my alma mater, the University of St Thomas where we will finally have mounted as a statue in our new STEM building after sitting for 10 years under a tarp.

Man, just build a goddam stone arch bridge like they did in the good old days. Something Something revolutionizing transit through cloud computing and increasing efficiency in the modern age.

As a Minnesotan, fantastic episode. I was completely riveted. Would love to hear an episode on the Metrodome collapse some day. That thing’s entire existence is one big engineering disaster

Native Minnesotan here. Love the podcast!

"let me know in the comments if you're still confused" i mean both perpetually and about bridge design yes

I'm not even done yet but I heard the phrase "moment of inertia" and I had war flashbacks to University Physics 1. I am but a humble physics student I dont want to deal with this torture. (Also calculating moment of inertia by hand is dumb. It involves integrals and I can never remember which one)

I enjoy the repeat of the lecture on connections for bridges from the very first episode on the silver bridge disaster, and that in both cases Alice instinctively went for the fixed connetion.

love that key moments feature where you can see where this show temporarily becomes liam's personal rant about football

why are you doing this to my sleep schedule

I've definitely pretended I didn't see asbestos a lot of times.

Honestly Justin's explanation of statics and beam theory was just about how they explained it to us at my school

Post Justin did a great job explaining why it was a cantilever and why it should have been not that. Thanks for the post-ness

"Pennsylvania is the worst I think" I can only hope that the inordinate amount of bridges we have in Pittsburgh are what skews our magnificent Commonwealth to be #1 in deficient bridges. Maybe an episode of the podcast dedicated to our entire city one day. I mean, I expect one way or another you'll just have to make an episode about the 'Burgh to unleash the floodgates of Philly banter. And 'floodgates' makes me think of Johnstown, but that doesn't count as Pittsburgh. Still a fitting episode for Pennsylvania hell content (Centralia too I suppose)

Justin, your mast climber story makes me wonder how engineers in construction even survive past, like, their 2nd week of work after college. Damn.

I fucking LOST IT at "P is stored in the beam". If only I could go back to undergrad statics and crack that joke.

Enjoyed listening to this on my commute, most especially because it's mostly on I-35.

First of all, this podcast is mega Second, you guys got me through my dissertation so cheers lads and lasses

@1:06:00 - It's amazing how much more concise and understandable Justin can make engineering explanations when he isn't constantly being interrupted by the two buffoons.

Interestingly, we don't name ANY of our bridges... It's the "35W Minnesota River bridge" in Bloomington, the "Cedar Ave Bridge" in Eagan, the "Bloomington Ferry Bridge" where there used to be a ferry in, um... oh, i keep forgetting that one. The "Hennepin Avenue Bridge", the "Stone Arch Bridge", the "Lake Street Bridge"... at least Stone Arch isn't just the street it carries. Are we missing something by not slapping people's names on these things?

And this is why I went into geoscience instead of engineering.

I can’t decide which is funnier: Justin saying “Yes” or Justin saying “No.”

This collapsed the August of the start of my freshman year of college at the University of Minnesota. They left the crushed train cars that had happened to be under the bridge around for a long time. Like a giant crushed a pop can. Also listening to all the lack of knowledge of Minnesota...（ｖ＾＿＾）ｖ