Labor was free because of slavery, so the economics were not the same. Current engineering has the concept of “over engineering” which is what cracked-up addicts in wall street call “building to last”, due to the “expense” of not being shortsighted on a quarter by quarter basis.
I think it’s just an assumption based on the mode of society at that time in history. If it was built in the 12th century it was built by what we would now consider slaves. In the 1100s the land was divided into fiefs and the lord of that land considered the people who lived and worked on the land as part of that land: serfs. Unless this bridge was an exception to the rule, then serfs would have undertaken all the labour that got it built.
Actually overenginnering is the thing with pre-modern structures, like the bottom bridge here. Survivorship bias played a role, where things they don’t build to last, evidently don’t last to this day, but mostly it’s because they don’t really understand the math behind all of it so they take the most conservative and the tried and tested rules of thumb when doing big structures. This is why big projects back then can take decades to complete.
In the modern day, we design specifically to balance durability and cost, and we are confident of our maths and understanding of material science to use the least amount that does the work for the design life that we choose.
From my pov I think you’re repeating exactly what I said, but I appreciate the additional details.
My last point is that “the design life we choose” is usually dictated by non-engineering forces. A 12th century king can throw resources at a problem. A 20th century governor cannot, and doesn’t care to. They care about the bridge lasting until the end of their term limits.
Labor was free because of slavery, so the economics were not the same. Current engineering has the concept of “over engineering” which is what cracked-up addicts in wall street call “building to last”, due to the “expense” of not being shortsighted on a quarter by quarter basis.
Was it slaves? I am not seeing any references to slaves building the original bridge online anywhere, where did you see that? :o
I’m considering most economic systems prior to…the last few centuries to be essentially slavery. If some random king owns everything…
Not the same as America’s slavery of course, nor is it necessarily legally structured slavery as existed in many societies, but nevertheless.
I think it’s just an assumption based on the mode of society at that time in history. If it was built in the 12th century it was built by what we would now consider slaves. In the 1100s the land was divided into fiefs and the lord of that land considered the people who lived and worked on the land as part of that land: serfs. Unless this bridge was an exception to the rule, then serfs would have undertaken all the labour that got it built.
Yeppers that’s the thought process. thanks for explaining better than me.
Actually overenginnering is the thing with pre-modern structures, like the bottom bridge here. Survivorship bias played a role, where things they don’t build to last, evidently don’t last to this day, but mostly it’s because they don’t really understand the math behind all of it so they take the most conservative and the tried and tested rules of thumb when doing big structures. This is why big projects back then can take decades to complete.
In the modern day, we design specifically to balance durability and cost, and we are confident of our maths and understanding of material science to use the least amount that does the work for the design life that we choose.
Good thing that’s not a problem anymore.
From my pov I think you’re repeating exactly what I said, but I appreciate the additional details.
My last point is that “the design life we choose” is usually dictated by non-engineering forces. A 12th century king can throw resources at a problem. A 20th century governor cannot, and doesn’t care to. They care about the bridge lasting until the end of their term limits.