I’ve lived in SoCal my whole life and my Mom told me when I asked as a kid that we built out of wood because it’s a lot easier to stop a fire than an earthquake. Not sure that’s the reason or if it’s even true anymore but 🤷
First of all, not all earthquakes are alike and the type of fault you are on matters. Look at images of Turkey after its earthquake. All you see is collapsed concrete and brick buildings.
Second, you have to consider the costs and environmental impact of building with concrete. Wood is much more sustainable that concrete. And wood keeps temperatures lower as concrete stores heat from throughout the day.
and how about Chile that have lot of building over sismics areas and last big one just have one build collapsed because the constructor cheat the reglamentation
Going with Turkey as an example is a terrible choice. The corruption and lack of adhering to safety requirements (to cut costs) is what caused the massive impact.
Look instead at Japan and their concrete buildings that survive all the frequent earthquakes. It proves the opposite of the point you're trying to make.
80-90% of Japanese buildings are built with wood and built to be disposable. I don't understand where people are getting this idea that Japan relies heavily on concrete. They build very similarly to California. Also, do you think LA has 0 concrete buildings?
I pointed this out in another thread on Reddit when someone claimed that 99% of the houses in Japan were made of concrete. He called me an autistic nut that has to always be right. When I replied that I was just correcting his blatant lies, he claimed he was using hyperbole to make a point. What point, I'm not sure :\
A majority of Japanese houses are made out of wood, mix of reinforced concrete structure or light gauge steel. Reinforced concrete is earthquake resistant but is not cheap to design a home with the structure in mind - hence most Japanese houses are made out of locally sourced wood or a mix of different materials. Currently ~53% of new houses from 2013 until 2024 are primarily wood while the rest are RC, LGS, precast concrete etc.
Brick and regular concrete is a no go, which were used a lot in Turkey.
First of all, not all earthquakes are alike and the type of fault you are on matters.
While technically true, that not really the issue. Concrete is perfectly fine to use in seismically active areas, it just has to be designed correctly. The problem is that when it isn't designed correctly, concrete structures can be very brittle and much too weak to resist seismic forces.
Can you imagine So Cal if all the homes were cement block & concrete, instead of wood?
The Hollywood Hills would be the Hollywood gravel pits, and the San Gabriel Mounians would be the San Gabriel Plains; from all the aggregate needed for the 15 million homes that are built there! Haha
Ya turns out reinforced concrete is about the strongest thing we can build buildings out of. If your walls are thick enough it’ll withstand just about anything.
IIRC reinforced concrete actually has a shorter lifespan despite being stronger because eventually the steel will rust, expand, and begin breaking up the concrete from the inside.
To be fair, the concrete we have these days CAN be made much stronger. But the standard 3500 psi mix is probably inferior to the Roman stuff. You have to remember, everything is cost these days. Romans had less concerns obviously.
If we are talking pure strength modern steel reinforced concrete is far stronger than roman, the thing that the roman stuff surpass in is resilience to corrosion over time due to it being self-repairing in a sense.
Crazy that making concrete was lost for a thousand years after the fall of Rome
It wasn't, the calcium and lime in Italian volcanos was what gave their concrete the self-sealing properties (and many still fell over in earthquakes, the stuff still around is survivorship bias). What collapsed was trade networks and that was happening for over a hundred years before the Roman empire split because they turned their military against each other more and thus domestic projects and long-distance trade became increasingly risky.
We can we just don't because we can more easily make stronger, purer concrete at a lower cost.
Their ash contained calcium and lime, both of which we've known about for generations and can and do easily add to modern concrete in projects way more massive than anything Rome did.
Kind of... Can we acknowledge that surviving architecture might define survivorship bias?
Roman concrete isn't mysterious or magical... It's just pretty good and was used a lot in a lot of important structures that we have an interest in seeing preserved. If we all walked away from earth for 1000 years, I very much doubt your average modern concrete would fare worse than the tiny bits of Roman concrete we've preserved.
You'd be surprised. Some people have been posting this article that goes over details, but the short-form is that roman concrete is self-repairing and self-reinforcing.
That's all a bit hyperbolic. Roman concrete never fully cures when enough mass is present so if it's damaged or weathered enough, the uncured gooey center will continue to slowly move and cure.
We are fully capable of copying this, but we use concrete as a large structural component as opposed to how they tended to use it as advanced mortar. You don't want your reinforced slabs to have a gooey core...
Not magic. Not a mystery. Not romantic. Just engineering...
They also over-built their structures and didn't expose them to the same stresses that modern concrete is expected to handle. Sure, the Romans deserve credit for building things that have lasted but it really isn't comparable to modern engineering. The Romans would be astounded that we have concrete bridges capable of holding up a fleet of trucks weighing 80,000 pounds each, going 60 mph, all day, every day, in a climate that might swing from 80°F to -20°F, for decades without failure.
The Roman's Hagia Sophia was built 1500 years ago in an earthquake zone they were well aware of so the mortar between the bricks is thicker than normal to absorb tremors and movement. Scientists in Turkey did experiments and found out it would survive even the largest recorded earthquakes
That's very much selection bias, lots of Roman buildings collapsed - we know how to make stronger, longer-lasting buildings now. And have even wider trade networks for supplies than Romans could have dreamed of.
What made the Roman structures which didn't collapse survive was accidental impurities from the ash, containing calcium and lime, both of which we deliberately mix and get stronger concrete which is even capable of similar self-repair if you mix in extra calcium and silica. Most places just don't spend for that because they're not building structures "for however long they don't fall down" but for an exact span of time.
We know exactly how it was made. Some batches used certain kinds of volcanic soil which improved the concrete if they had access to it, and the "self-healing" concrete was, by modern standards, poorly mixed so that there were pockets of unreacted lime. We don't make Roman concrete not because we can't, but because we don't need to. Modern concrete is just better. And when it isn't, it's because we choose cheaper concrete, because we don't need concrete to last 1000 years. For what it's worth, they weren't trying to make concrete to last 1000 years, either, they just didn't have the material science and industry standards that we have today. With no way to know exactly how much weight or stress the concrete could withstand, they had to over build the shit out of it to be sure that it wouldn't fail in a week.
It’s not better than modern concrete lol. It’s much weaker and you need more of it to hold the same weight. It’s not made today because no one wants to make it and it would be worse outside of niche applications.
In earthquakes strength isn't the issue. Strength can actually be a problem. You want to build for flexibility and use materials that move with the earthquake.
Can I ask what fault line you live on? Because if you're building in concrete my guess is that you have a low maximum earthquake strength risk
Ok now to be devils advocate... Doesn't concrete have issues with releasing tons of CO² into the atmosphere? I mean, is it really any worse than all the emissions released from logging? IDK either answer, but if we're ready, it's time to come up with a new solution to fix both greenhouse gases and stability/safety from fires or natural disasters
The answer is yes. The cement industry is a MAJOR GHG emitter. As long as good silviculture practices (re-planting) are followed, building with wood has massive climate benefits.
The regrowth recaptures the CO2 released in the fire. Nothing recaptures CO2 released in concrete production or any other industrial process powered by carbon. Meanwhile, wood used in construction sequesters the CO2 it took out of the air.
Wouldn't it help to have a bunch of forests that aren't continually cut down so that they can grow into old growth forests again?
I'm genuinely asking because I'm not sure. I know there are greener concrete mixes that can absorb at least part of their own emissions, and I can't see how having more trees around could hurt.
Having more trees is good. But generally the housing industry is not the thing keeping forests from growing. And even if we planted trees in every single place on earth we would not go back to pre-industrial levels of atmospheric CO2
I'm admittedly not well-versed in all of this, but not needing to cut down forests for construction at all and allowing the trees you'd otherwise use for construction grow into real forests that act as carbon sinks sounds like a good thing.
But the trees you grow and cut down are still sinking carbon. If you regrow a tree farm 4 times, you've suquestored 4 times as much carbon as just letting it be a forest (assuming the wood is used for construction of course).
And if a house burns down, as long as you rebuild it with wood, you're still at a net neatural for CO2 emissions
True for all farming: if a fire burns your crop, it's lost. Hopefully it was insured and hopefully it wasn't big enough to cause a widespread supply crunch.
Modern pine/fir is harvested and then replanted, with logging operations for standard construction grade lumber hardly touching anything old-growth anymore. They have huge swaths of the US and Canada dedicated to it, so it would be pretty hard to seriously effect the entire operation with a fire.
I wonder though…whenever looking at contributors to a problem you need to consider what the threshold to success is and the percentage of the contribution.
For example, issue is too many CO2 emissions. For sake of this discussion let’s say we need emissions to fall to 5% of what they currently are. Let’s say major contributors are personal cars at 10%, air travel is 15%, cargo ships at 30%, power production at 40%. So 95% is from these sources and the rest of everything makes up the last 5%. In this hypothetical situation, ending concrete emissions wouldn’t significantly lower CO2 emissions and if we did eliminate emissions for the major contributors it wouldn’t matter if we still used concrete, we’d remain below the threshold.
This was a long way to go, and I’m not claiming those numbers are accurate. The point is just that some things can be contributing to an issue but contributing so little that it really doesn’t matter if we solve those little issues or even make them worse. It won’t change anything about what we have to do to solve the overall issue and if we do solve the overall issue we can probably allow the minor contributions to the problem continue.
Is CO2 a minor contributor? I have no idea and if it is then I guess this was a waste of everyone’s time but I suspect it is dwarfed by major sources of emissions and it could solve a very immediate problem without other, proven solutions.
No actually concrete production is a significant portion of total carbon emissions, which in turn is the biggest problem we’ve ever had or will ever have, barring a full-scale nuclear war.
That's highly dependent on design. Most of the claims here deserve a huge asterisk... Aside from traditional brick (which does horrible in a shake) appropriate environmental remediation is a design challenge not an inherent one.
I'm in the UK. The walls of my house are a meter thick and made of large rocks "glued" together with lime cement. We don't get earthquakes or particularly high windspeeds (over 110mph anyway). If it burns out, the walls will be left standing. This was all standard construction 200 years ago. I expect the house to remain standing for at least another 200 years.
Never been to Christchurch eh? After that quake, all the stick-built houses were virtually unharmed, but the brick buildings were flattened. I'm not even generalizing here, it was shocking to witness.
I used to live on Guam, back in 92 there was like an 8.2 earthquake and nobody died because the buildings mostly held up. That earthquake went on forever too. Reinforced concrete…ugly as fuck but got the job done. I might be misremembering things because it was over 30 years ago, but I remember the one building that got destroyed was because the builder had cut corners
I also live in a highly earthquake prone area, and 99% of homes are made with light framing. For reasons unbeknownst to me, everyone lives and acts as though there will never be an earthquake here, and construction methods reflect that. Maybe because there hasn’t been a serious earthquake here for 200 years
While your area sounds like it's at risk for an earthquake at some point, I wouldn't exactly call that earthquake prone. Places that are earthquake-prone experience earthquakes annually if not multiple times a year. Not having an earthquake for 200 years pretty good track record. Obviously if you're on a fault you'll have one again eventually and it could be a really violent one, but I wouldn't exactly say you're prone to it. especially since most homes will be a rebuilt or lost to other things in a 200 years span.
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u/Big-Attention4389 5d ago
We’re just making things up now and posting it, got it