Racing Turtles

Harrison Saunders

I Have But One Egret

Lamar St Bridge over Lady Bird Lake Austin, Texas

Tight squeeze.

“Made her a bridge to the window she always stared at but could never reach.“

(Source)

here’s a compilation of different people driving box trucks into a low bridge over and over

It’s worth knowing a few fun facts, courtesy of 11foot8.com:

The guy who runs the website (and owns the cameras) says he sees a lot more trucks pull up to the stoplight, look at the warnings, and turn off onto the side road, but about once a month, someone hits the bridge.

the penske business is probably sick of this shit

Since all the information is from 2017, here some updates from April 2022 according the website 11foot8.com

The Truck Peeler 3000

surely this is a good idea that doesn't have the capacity to end real fuckin badly

Bridges aren’t supposed to have weight restrictions on them. That is, they don’t come with weight restrictions on them when they’re new. So a bridge with a weight restriction on it is a sign that something has gone wrong and the bridge does not meet current standards.

The maximum weight that a vehicle is allowed to carry on the Interstate System per federal law is 80,000 pounds gross vehicle weight (with a max of 20,000 pounds per axle). That’s 40 tons. That limit applies to every inch of pavement, not just the bridges. Since this is a known cap, a new Interstate bridge will be designed to accommodate an 80,000 lb GVW load on it. You could say the bridge’s weight limit is 80,000 lb/40 tons but that doesn’t really have much meaning, because a load higher than that would be illegal to transport on public roads anyway, and the road leading up to the bridge has the same weight restriction. (In practice, the bridge doubtlessly will be designed to have a little bit of let to it just in case some idiot tries to squeak by a few hundred extra pounds.)

Now, note that that law applies to the Interstate System only, because the federal government only has a governing interest in the Interstate System (and other roads that together make up something called the National Highway System) because they partially fund it. Most long-distance roads are owned and funded by the states. The states could theoretically set lower standard weight limits and/or design bridges with lower weight limits...but in practice they don’t.

One, because all of that 80,000 lb GVW traffic on the Interstate system has to go somewhere when it exits the system.

Two, because a group called the American Association of State Highway and Transportation Officials (AASHTO, who are best known for picking the road numbers) maintains a catalog of standard components for making bridges that meet Interstate System requirements. Engineers are expensive on a per-hour basis, so if you can direct your engineer to use standard components and make a standard bridge, that’s a lot cheaper than having them design a bridge from scratch to go over the creek in Nowheresville. As a result, most new bridges meet Interstate standards and have an 80,000 lb GVW rating even if they aren’t on the Interstate system. (This is also why all new bridges kind of look the same, but we’re not worried about how boring the bridges are for the sake of this post.)

So a bridge only has an explicit weight limit if it has been damaged in some way (through failure to properly maintain it usually) or because it predates the application of Interstate System standards and the standard AASHTO bridges.

Older bridges often have other problems in addition to the weight limits: many older designs are what we call “fracture critical”, which means that if one component of the bridge fails the whole thing collapses. Modern bridge designs have redundancy designed into them so that if one beam fails the other beams will carry the load until the damaged beam can be replaced. Older bridges also often don’t meet other standards, like height (16 ft clearance) and width (12 ft per lane plus 14 ft for shoulders) requirements.

Biden isn’t advocating eliminating weight limits and letting it be a laissez-faire free-for-all where trucks can just go wherever they want. He’s advocating for replacing bridges that carry weight limits with new ones that don’t have them.

wow i got absolutely schooled thank you for all this this is really informative. i have learned so much

This is a great explanation of what the fuck Biden was talking about in his tweet. because I will freely admit that I also went ".......wtf?????" when I read it. So thank you.

Today I learned about civil engineering.

i’m detecting wikipedia bridge drama

ok but then I looked up “culvert” on Wikipedia

So how do they make that?

This just raises more questions for me 🤦🏾‍♂️

what the FUCK

this is whats called a ‘coffer dam’, you basically build some walls, drop them in the water, tie them together, and then pump out the water from your new hole in the water so you can build while staying dry its oddly not that hard- the flippin ROMANS were able to do it with logs and mud

occasionally particularly devious people would use this to hide treasure or tombs underneath the river so its not only impossible to find but impossible to get to without an engineer division

that last part gives me ideas for campaigns

“Not that hard - the ROMANS were able to do it” - people seriously underestimate how advanced some ancient cultures were and the organized effort it takes to come up with something like this and actually implement it. The Romans had heated floors, glass windows and ceilings that could be rotated to reflect what you were eating (forests for game, sea landscapes for fish). Hell, the Greeks built cameras and moving robots. The Minoans, who lived four thousands years ago and were wiped out by a tsunami three times as powerful as the one which devasted Japan in 2011, had running water and modern toilets. And let’s not get into how China basically invented everything centuries before anyone else. 

Bottom line: just because someone was already doing it thousands of years ago, doesn’t mean it’s not very difficult and an extraordinary feat of engineering.

someone: you build how many bridges on a single military campaign…?

Caesar: what, like it’s hard?