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Had the radio on yesterday, they were talking about Haiti then the conversation went to the subject of building codes here in the US.

How does one build against both a hurricane and an earthquake? From what I understand there are buildings in Florida and California that would fail codes if build in the other state: Build to sway in California would be blown down here in Florida as very solid anti wind construction would crumble if the earth moves.

I wonder who would fare better: Earthquake in Miami vs. Hurricane in LA?
Both need the same building codes.

Structures are considered earthquake-proof if the foundation, floor, walls, and roofs are all tied together so they won't separate when tipped over. Earthquakes and ocean waves behave the same, they appear liquid and apply a horizontal force on structures. Unsafe buildings have roofs that collapse when the walls are tipped over, causing anyone inside the building to be crushed, both from the collapsing walls and the roof. The desired effect is a building that can roll over without collapsing.

Taller structures are built to be flexible and bend with side forces, rather than break. To stop tall buildings from tipping, studies are made of the ground they are built upon, and piers are driven down into bedrock, allowing liquified ground or waves to pass around the buildings without taking them down. The science is pretty straight-forward - but the inspection process is needed to assure all aspects work together. Even the best architectural plans can be built incorrectly, or engineered designs can be incorrect and following them without understanding the desired otcomes will result in failures.

I know of one tower in Vegas that was built up to the 20th floor, and a seasoned Super questioned why rebar was not connected in the concrete slabs. The inspectors missed it, and the building had to be taken down back to the mistake and rebuilt. That tower today is only half the height originally wanted.

Some concrete slabs use a design where a rebar-like bar is embedded in the slab, crisscrossed with other bars under tension to keep the entire slab together. Cutting into the slab at the wrong spot can cut this tension bar and the entire floor will explode.

Needless to say, few buildings in Haiti would be this sophisticated. There was one shot of an apartment complex that tipped over, but did not collapse, which shows some advanced methods were followed in some places.
When my ex-wife participated in week-long mission trips to Central or South American countries to build houses and churches, the first thing that was done was to pour a big, solid concrete slab, and a steel framework was built anchored to it. Then all concrete blocks were fitted by the workers with steel rebar and attached to the framework. The roofs were big sheets of corrugated galvanized steel, bolted on. Organizations like ADRA (ADventist Relief Agency) and Maranatha always built to codes that exceeded local codes for withstanding earthquakes and hurricanes. That is why the next time a hurricane or earthquake hit, it was the ADRA- and Maranatha-built houses, schools, and churches that were always left standing, for everyone else to shelter in.
My wife is a specialist in green architecture, and a certified inspector for both residential and commercial construction. Her answer for both earthquakes and hurricanes is monolithic dome construction. Granted there is a size limit in such buildings, but this is Haiti we're talking about. They aren't likely to have use for high rises (especially now).

Monolithic domes and earthquakes

War Bonnet Domes and earthquakes
I really like the idea. In fact, it has been known for a long time, that Quonset huts are very strong, easy to construct, and last a long time. They are also very cost effective.

I would think a tiny dome like this one, would be cheap, and could be stacked together, in large numbers.
My wife has already told me that if we find the cash to build our own home, it'll be monolithic dome.
A monolithic dome IS a tied-together structure. It is generally more expensive than simple walls and roofs tied together, but they behave the same.

Unless a Quonset hut is tied to a foundation, then if tipped on its side (the result of earthquake liquefaction and sideways torque), it may still collapse. This is dependent upon the spring-tension of a curve no longer centering its weight straight down. Think of it as an A-Frame with more curve to it.

A dome is much the same. The expense is in constructing something which is rigid enough to maintain its shape when tipped. A sphere should work great. Geodesic architecture came out of UofM. I remember walking through the experimental architecture attached to the side of the Architecture and Design School in Ann Arbor. You walked through a deodesic framework next to Ionic Greek coluimns.
A monolithic dome and a geodesic dome are not the same thing at all. A monolithic dome is one single piece, rather than walls and a roof. Basically, a rebar frame is erected and shotcrete is applied. Cost to build is actually no more expensive overall than a standard building of the same size. On top of that a monolithic dome costs half what a standard building costs to heat and cool.
Rebar alone does not suffice to tie together a structure to make it earthquake proof. The idea is to tie it all together. Most domes I've seen built are made from precast sub-assemblies. to cast a dome as a single unit, curved inside and outside walls are set up similarly to how poured basement are made with forms, and that is very complicated to have internal tied reinforcements centered in such a system.

I'm sure there is a system that may do it better than I've seen it done, but most tied together structures are done with cables or bars under tension. I'm not sure how that is done along a curve. Poured domes generally have loose fill rebar.
I suggest you study state of the art monolithic domes. They are not precast subassemblies.

Look at this
My guess is that these domes could be constructed in huge quantities, and made so as to be stacked within each other, and then shipped in mass, in order to fulfill an emergency call. They could even be set down on a leveled dirt/sand base, and then be picked up again, when the emergency is over.

Bill, you are thinking Big here. But these domes can be small, and fulfill a niche, such as what is happening in Haiti, or some other disaster.
Or buy an old concrete water tank and turn it into a house.

There was a large concrete water tank with a domed roof nearby that was for sale by the water deptartment.
I thought about buying it and turning it into a house. It was big enough to have two levels inside. It should be water proof and hurricane proof.
Someone else bought it, tore it down, and made a parking lot.

Put a deck on top with a chain gun, and it's zombie apocalypse ready.