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This is a very odd design document and it makes me think this author has thought a lot about materials and buildings but not actually built anything. The steel

• Animats 5y ago
  "rigid steel structure" Steel is springy. Tall steel-framed buildings and bridges routinely sway in wind, which is usually harmless to the structure but annoying to occupants. Unless you get harmonic oscillation, where the energy stored in the motion builds up, which can be a problem and has destroyed bridges. Much of seismic design involves connections which raise the resonant frequency of the structure so it can't oscillate at a low frequency with high amplitude. That's what those triangular reinforcement beams one sees in San Francisco really do. It's also what all those rectangular trusses under the Golden Gate Bridge do. Those were a retrofit. Wood's flexibility usually causes problems at joints. Nailed joints are not very strong in tension. Most construction today in areas with earthquakes or high winds involves metal reinforcement of joints. There's a collection of galvanized sheet metal parts for that at any Home Depot. Tension joints for wood are seen in classic Japanese construction, in boats, and in cabinetry. Not so much in modern houses, partly because they work better in hardwood. I wonder if, in the next installment, the author will discuss those.
  • rsync 5y ago
    I would agree that connections should be steel - I like the thick gauge, heavy duty simpson connectors, plates and column caps, etc., which allow you to lock in beams and columns with 3/4 machine bolts, etc.: https://www.strongtie.com/boltedcolumncaps_columncaps/cct_cap/p/cct https://www.strongtie.com/boltedcolumncaps_columncaps/cct_ca...
  • clairity 5y ago
    > "Steel is springy. Tall steel-framed buildings and bridges routinely sway in wind, which is usually harmless to the structure but annoying to occupants." exactly, i recently mentioned my swaying-in-an-earthquake story[0], which was in a class A (steel+concrete) highrise office building. driving steel into the ground doesn't automatically mean it will rot and/or break in the first earthquake/windstorm that hits, even if that's a general possibility, given that engineers do think about that stuff when designing buildings. the gp comment is classic bullshit, plausible sounding but unconcerned with truth. [0]: https://news.ycombinator.com/item?id=29665129 https://news.ycombinator.com/item?id=29665129
    • rsync 5y ago
      You misunderstood my comment about steel in the ground ... I was trying to convince the OP that they don't need to worry about the corrosion since even in terrible circumstances the steel still lasts quite a while. With regard to your skyscraper experience: I'm not sure this is an apples-to-apples comparison. Skyscrapers are not made of skyscraper-height columns - they are a stack of elements that are connected every X height that has a well known flex per connection. It's also (hopefully) a uniform flex at every connection. But a smaller building would, indeed, have unbroken steel members (like a column) and you might "successfully" connect them to one another with an incredible amount of rigidity. It will either be tremendously strong throughout (good for you) or there will be some tiny piece of the chain that isn't as strong and can fail. I would be confident attempting this on a very small building. I would be hesitant to attempt this on a medium, two-story building. I would want wood framing. For aesthetic reasons, I would want that wood framing to be big timbers. I'd rather spend my money on those than on stainless steel roof framing :)
• mikewarot 5y ago
  Steel beams buried in the ground, no matter what they're made of, are going to rot away quite rapidly if they contact any other metal, due to galvanic corrosion. I think you'd be better off with basalt fiber reinforced concrete for anything going in the ground. It's going to be strong, and it won't rot.
  • entangledqubit 5y ago
    There is also basalt rebar. Last I checked, some building codes allow equivalent 1:1 tradeoff with classic rebar - even though the basalt rebar is stronger. From what I understand, basalt rebar does not have the usual problem of regular rebar where oxidizing (rust) expansion can cause cracking in concrete. Additionally, the temperature expansion rates are much closer (rebar vs concrete). My main hesitation would be that it is relatively new so we don't have that much data on how well it ages. Overall, it seems better than rebar classic by far (other than cost - which hasn't been scaled) - but I don't build structures for a living.
    • SECProto 5y ago
      > Last I checked, some building codes allow equivalent 1:1 tradeoff with classic rebar - even though the basalt rebar is stronger. Basalt rebar has a much lower elastic modulus, so when it fails, it fails. Steel on the other hand has a much larger elastic region - where the steel stretches while still carrying the same load. Part of the benefit of reinforced concrete is elastic failure - essentially every (properly) designed reinforced concrete structure is designed to fail with the tensile side of concrete cracking while the steel rebar still caries load, giving visual evidence that the concrete has failed. This is called elastic failure. This works because steel has a large ductile range. Basalt rebar doesn't fail the same way, so substituting it 1:1 seems inappropriate, regardless of it being stronger (per unit area). I did find one random study[1] that substituted basalt rebar 1:1 with steel and compared the failure modes, and found that basalt-reinforced had cracking load essentially the same as a steel-reinforced, but a much larger ultimate load. Interestingly, the higher ultimate strength more than makes up for the much lower elastic modulus. [1] https://www.icontrolpollution.com/articles/investigation-of-structural-members-with-basalt-rebar-reinforcement-as-an-effective-alternative-of-standard-steel-rebar-.pdf https://www.icontrolpollution.com/articles/investigation-of-...
• avereveard 5y ago
  > If I had an unlimited budget at some point on the price scale you can just build a titanium cast for a house and pour molten rocks in, probably a basalt. what's the yield strength of igneous rocks? maybe the roof need to be arched.
  • MR4D 5y ago
    So, a cave in a basalt mountain then. I like your thinking. ;)
    • samstave 5y ago
      What are the load-baring capabilities of a Basalt Cave during the Apocalypse? /MontyPython style...
      • sedatk 5y ago
        Is that a European basalt cave, or African?
  • titanomachy 5y ago
    Is that something that we've actually done at any kind of scale?
    • samstave 5y ago
      On a global scale, probably, yes... but I'm either 1 or 0 correct.
    • wongarsu 5y ago
      Many cold war bunkers are kind of like this, but using rock that's already in-situ: start with solid rock (either in a mountain or in bedrock), remove some of it, in the cavity add linings of concrete, copper and steel to enhance properties as desired (copper for better EM shielding).
    • Anon1096 5y ago
      Not the same, but the Pyramids of Giza are essentially huge rock houses. I don't think they provide very modern amenities though :)
• skylanh 5y ago
  > author has thought a lot about materials and buildings > but not actually built anything. That was my impression. As soon as they started talking about unenforced concrete pilings (drilled? monopile?) to bedrock and stressed steel framing I wasn't certain I would enjoy anymore or that it was a good use of my time. I think costs at this stage are unrealistically low "probably in the neighborhood of $1000-2000 per square foot ... (8 to 16 times as much as conventional construction)". ~$250-400 sq ft is the cost of modern labour expediated and material optimized building. They're describing stainless steel framing with what would be (what?) 316 SS in S-beam with a custom end plate? A blob of rolled 1" x 6' 316 SS is $200. There are the examples we could draw from: https://en.wikipedia.org/wiki/List_of_oldest_known_surviving_buildings https://en.wikipedia.org/wiki/List_of_oldest_known_surviving... https://en.wikipedia.org/wiki/L%27Anse_aux_Meadows https://en.wikipedia.org/wiki/L%27Anse_aux_Meadows https://en.wikipedia.org/wiki/Ancestral_Puebloans https://en.wikipedia.org/wiki/Ancestral_Puebloans Material wise we'd look at clay, solid high-density rocks, non-ferrous metals (lead, aluminum, copper, tin), dense naturally mold resistant woods (cedar, redwood), high density with high oil content woods (https://en.wikipedia.org/wiki/Lignum_vitae https://en.wikipedia.org/wiki/Lignum_vitae), and easily replaceable sacrificial surfaces, dirt with live plant, cobble rock. Building techniques aren't going to improve with technology, we already have examples that have lasted -- we're looking at building a heap temple with ancient style water and sewers. This is either a rock temple or a log-house with highly resistant woods. Either we aim for a light-weight footprint or we find solid rock for building on. Solid rock is the most appropriate. Our fasteners are all based on managing gravity. Rock with concave and convex connections under gravity. Wood pegs in non-load bearing configurations. Lead sheets with crimped folded seams. Solid copper sheet trays with crimped folded seams in rock trays. The first thought should be "what happens if I drive a truck into the side of this building 10 times?" And the answer should be "not much, you move a few things around, but there is limited stressed coupling, and things rest on top of each other." If you do substantially damage the building, all you should be doing is reassembling the pile. I called the author out for not having built anything, and in honesty, I haven't built using these ancient approaches, so, perhaps this is a self-destructing prophecy.
  • lstodd 5y ago
    No you're right. Stainless steel is insane, in those conditions it will corrode in several decades, if not faster. Foundation is just laughable, it won't last 200 years, much less 1000. Like you say, a structured pile of rocks with everything else easily replaceable is the recipe. The question actually should be not of a several truck hits, but of several fires, like, complete burnouts. That's what would happen in 1000 years.
• tyingq 5y ago
  >makes me think this author has thought a lot about materials and buildings but not actually built anything Here's an interview with the author: https://on.substack.com/p/what-to-read-construction-physics https://on.substack.com/p/what-to-read-construction-physics and his LinkedIn page: https://www.linkedin.com/in/brian-potter-6a082150 https://www.linkedin.com/in/brian-potter-6a082150 Anything's possible, of course, but he does seem to have the right credentials and experience for the subject matter.
• phkahler 5y ago
  >> If I had an unlimited budget and was aiming for >1000 years I would pour the piles to bedrock with stainless rebar... Yeah they reject reinforced concrete, but the reason it doesn't last is the type of rebar used. To then site stainless later seems odd. IMHO our roads need to be built with stainless rebar.
• tzs 5y ago
  > If I had an unlimited budget and was aiming for >1000 years I would pour the piles to bedrock with stainless rebar inside fly-ash concrete and top those pilings with plate connectors into which you could socket large wooden columns (perhaps 8x8) and build the structure with large wooden members connected with steel connectors and column caps, etc. Are there any existing buildings constructed that way that have stood for >1000 years? If not, my approach would be to copy an existing building that has stood for >1000 years in a region that has had several of the same kind of natural disasters that happen at the place I'm going to be building.
  • tempestn 5y ago
    Could be prone to some survivorship bias.
    • maxwell86 5y ago
      Sure, but what's the alternative? Dig out all other buildings that failed over the last 1000 years, figure out how they failed and why, and take action? You can just copy what is known to work instead.
      • hwillis 5y ago
        Or like, look at any of the million dilapidated houses and realize that 1. most houses leak at some point and 2. termites eat wood. Then conclude that actually, maybe .0001% of wood houses lasting for 1000 years is not actually good evidence that wood is a material that easily lasts 1000 years. Then think twice about using wood. Personally I'd a concrete dome: https://en.wikipedia.org/wiki/Pantheon,_Rome https://en.wikipedia.org/wiki/Pantheon,_Rome
        • maxwell86 5y ago
          The claim here is that one would look at _ALL_ 1000+ year ld buildings, and then decide what to build. You are building the strawman of looking at _ONE_ 1000+ year old building, and then building that because it must work. Nobody is arguing about this, and probably everybody here would agree that doing this is a bad idea. --- With that out of the way, there aren't many 1000+ year old buildings made out of wood. There are some, e.g., japanese temples, that IIRC have burned a couple of times along the way, but are 1000+ year old and build out of wood. But most buildings in the 1000+ year old range are made out of stone and only partially out of wood (cathedrals, etc.).
• rlaanemets 5y ago
  I would like to know more reasoning behind choosing a frame without diagonals. I have had to repair many old garages and shacks which had wooden frame but lacked diagonals. Often we had to push them upright and brace the frame with diagonals to avoid problems in the future. A cube-like building frame without diagonals or shear walls is unstable and does not sound so strong or resilient at all.
  • clairity 5y ago
    in a typical wood-frame wall, it's (usually) plywood nailed to the studs that acts to resist shear forces. you shouldn't need diagonal cross-members, unless there's not enough structural plywood cladding or not enough studding.
• roywiggins 5y ago
  I'd carve it out of a cave somewhere. https://www.cnn.com/travel/article/anglo-saxon-cave-house-scli-intl-gbr/index.html https://www.cnn.com/travel/article/anglo-saxon-cave-house-sc...
  • strken 5y ago
    The dugouts in Coober Pedy are a modern example of this. I'll bet they're still there in 1000 years, albeit with damage to the exterior facades.
    • hwillis 5y ago
      With .5" of monthly rainfall and nearly no seismic or insect activity to speak of, you could make any house in Coober Pedy last nearly forever.
  • rrobukef 5y ago
    Here is a testimonial about a modern cave home: https://dengarden.com/misc/The-Pitfalls-of-an-Underground-House https://dengarden.com/misc/The-Pitfalls-of-an-Underground-Ho...
• voisin 5y ago
  > I would only use steel members if the span called for wood that was too big (like a 24' span needing a 8x14 or whatever). What about laminated timber to achieve these spans?
• Spooky23 5y ago
  Agreed on the design. I worked in a post and beam barn built in the 1600s. It will be there in 2200. Basically, if you need the roof maintained and those buildings will last forever. Personally, I’d do a stone foundation with post and beam. Over 1000 years, luck and location mean more anyway. Chances are the building will be flattened by a war or other calamity over that timeline.
• hwillis 5y ago
  Okay, so your step #1 for building a 1000 year house is to just... have a house that never has any leaks or termites? I can see some issues. If you want something to last, you plan for when it does go wrong. You should be designing a house that survives ten once-in-a-century floods and storms. Freezing pipes. Hot and cold. Termites, carpenter ants, mice. > ... which also means that unburied steel, protected from elements, up in the air, is going to last more than 1000 years. Rust is protective. That's why cars can rust so quickly, because vibration breaks the rust flakes off and exposes steel to more air and water. Steel beams are subject to bending and vibration. Steel buried underground is not. A larger problem is also that rust is expansive. I'm not positive what you mean by plate connectors, but nailed tie plates push their nails out over time. Screws and bolts work fine. The biggest problem comes with using treated wood and steel together. Treated wood, even the non-arsenic ones, use copper compounds. That causes galvanic corrosion. It'll even eat through zinc-coated steel. Galvanized steel is enough for at least a couple decades, but I have no idea about a millenium.
• Retric 5y ago
  I think you must have skimmed some parts. He isn’t burring steel into the ground. It’s only to be used inside the buildings shell and above the foundation. Thus it’s generally going to stay dry and mostly avoid significant corrosion issues, especially considering the generous safety factor suggested. The foundation is concrete piles to bedrock supporting a floating concrete foundation. Clearly that limits building locations, but plenty of places have bedrock reasonably close to the surface.
  • Cogito 5y ago
    The point you are replying to is that stainless steel is unnecessary, because 'normal' steel will ast more than 1000 years in the conditions described.
    • Retric 5y ago
      Not when one of the assumptions is that the shell will be seriously compromised at some point. Stainless steel is just another durability vs cost tradeoff, but it could be what makes the difference between repair vs rebuilding and it’s not that expensive. Wood for example could hypothetically last that long, but both fire and leaks are a real concern.
• hilbert42 5y ago
  "If I had an unlimited budget and was aiming for >1000 years I would pour the piles to bedrock with stainless rebar inside fly-ash concrete and top those pilings..." What would situation be if you used proper hot-dipped galvanizing instead? (And I mean proper quality hot-dipped galvanizing, not the usual 'toy' stuff that passes for galvanizing these days.) I've a good reason for asking, as I've an example of galvanizing that is in such good rust-free condition after being exposed to the weather and elements for 65 years that I would not have believed the fact unless I'd actually known its background and seen its condition, which I've done on multiple occasions for reasons I've explained below. The galvanizing in question involves an extant clothesline that's still rust-free and in good condition, it consists of three galvanized, multistrand (7 strands if I recall correctly) of clothesline wire that span the full length of the backyard and that terminate on wooden poles with horizontal 'T' beams spanning them (it's a typical clothesline that everyone's familiar with). The clothesline was installed in the backyard of my patents home in the mid 1950s and in 1957 an electrical conduit tee junction of 3/4" diameter (for joining conduits) that was made from folded steel was wrapped freely around the middle clothesline and a dog chain attached. This meant that the dog could pull the tee junction along the line so that he could gain almost full access to the total area of the backyard. Despite the wear and tear on the clothesline from the steel in the tee constantly sliding over the line—to wear that's even extended to the galvanizing being worn off from the high points of the strands of wire by the steel tree to the extent that it's exposed the underlying bear steel yet nevertheless this clothesline still shows no signs of rust after 65 years. I've studied chemistry for some years so I understand how galvanizing works but I still find it incredible that this galvanized wire is still rust-free after 65 years. Frankly, I find it so astonishing that every time I visit my parents' old home I cannot but help to cheek up on the status of said clothesline. Incidentally, little remains of the electrical tee junction, it was made of mild steel and painted black, the paint offering little protection and there would have been no paint that the point of interface between the steel and the wire.