Revolutionizing Bridge Design: A Vision of the Future

Zero-weight bridges

Imagine a world where bridges defy traditional engineering constraints, floating effortlessly above waterways without the need for supports or suspension cables. This is not a scene from a science fiction novel; it’s the vision of a groundbreaking bridge design that could change the face of civil engineering and architecture.

The Genesis of an Idea

A decade ago last week, I invented a novel material I called “carbon foam”. Made of graphene spheres with vacuum interiors, it boasts a density similar to helium, its high buoyancy at ground level making it possible to make virtually weightless structures. With very many possible applications, from floating Avatar-like islands in the sky to my Sky Lines hypersonic air travel and tethered floating architecture, this material laid the foundation for a new era in construction, where the impossible becomes possible.

Adapting the Vision

The idea soon evolved, allowing for non-spherical containment and variable density. By simply pumping air in or out of a sealed structure, still made of graphene with intricate, flowing internal structure, the sort we’re rapidly becoming accustomed to AI designing, the material’s weight can be adjusted, paving the way for structures that are both light and adaptable.

A Bridge Like No Other

Enter the bridge concept: a single-span structure, free from the constraints of weight. This design eliminates the need for support columns, allowing for construction from one end to the other, as long as desired. Picture the San Francisco Bay, graced by a new single span bridge, a single gentle arc sitting elegantly alongside its historic counterpart, but without any suspension or columns.

Furthermore, it can be constructed from one end, all the way across, the entire arc only connected at one end until the final days when it is joined to the highway at the other end.

Tackling the Wind

A key challenge for such a structure is wind. Traditional bridges use heavy materials and suspension cables to counteract wind forces, but this innovative design demands a different approach. Enter adaptive aerodynamics, powered by AI. Structures such as spirals and aerofoils, dynamically adjusted by AI algorithms, would balance and greatly reduce the wind load, ensuring stability and safety.

The Warren Truss: An Old Friend Revisited

The Warren Truss, a design known for its stability and strength, finds new life in this concept. In a weightless world, its potential is fully realized, offering unparalleled structural integrity without the burden of heaviness.

But we have AI now, so we can start with the Warren Truss as inspiration and use AI to simulate far more elegant, aesthetic and curvy mesh solutions to the various forces. Then, having used adaptive AI aerodynamics to reduce wind forces, the new meshes could produce bridges that are very beautiful and minimalist.

This is not just about creating a functional bridge; it’s about crafting a piece of art. AI simulations enable the design of aesthetically pleasing structures that are both simple and beautiful. The bridge’s design, while serving its primary function, would also stand as a testament to the harmonious blend of technology and art.

I tried to get a pretty AI illustration of a new San Francisco Bridge, but since AI draws its inspirations mostly from existing imagery, every attempt it made still had support columns or suspension structures.

Here is one of the better ones. After several more attempts very, very clearly explaining the requirements, I lost patience:

A Visionary Future

This bridge would be more than a pathway over water; it would blend our past and future where traditional design principles meet cutting-edge technology. It’s a promise of what can be achieved when we dare to reimagine the foundations of our world.

A potential architectural nightmare

I read in the papers that Google’s boss has rejected ‘boring’ plans for their London HQ. Hooray! Larry Page says he wants something that will be worthy of standing 100 years. I don’t always agree with Google but I certainly approve on this occasion. Given their normal style choices for other buildings, I have every confidence that their new building will be gorgeous, but what if I’m wrong?

In spite of the best efforts of Prince Charles, London has become a truly 21st century city. The new tall buildings are gorgeous and awe-inspiring as they should be. Whether they will be here in 100 years I don’t much care, but they certainly show off what can be done today, rather than poorly mimicking what could be done in the 16th century.

I’ve always loved modern architecture since I was a child (I like some older styles too, especially Gaudi’s Sagrada Familia in Barcelona). Stainless steel and glass are simple materials but used well, they can make beautiful structures. Since the Lloyds building opened up the new era, many impressive buildings have appeared. Modern materials have very well-known physical properties and high manufacturing consistency, so can be used at their full engineering potential.

Materials technology is developing quickly and won’t slow down any time soon. Recently discovered materials such as graphene will dramatically improve what can be done. Reliable electronics will too. If you could be certain that a device will always perform properly even when there is a local power cut, and is immune to hacking, then ultra-fast electromagnetic lifts could result. You could be accelerated downwards at 2.5g and the lift could rotate and slow you down at 0.5g in the slowing phase, then you would feel a constant weight all the way down but would reach high speed on a long descent. Cables just wouldn’t be able to do such a thing when we get building that are many kilometers high.

Google could only build with materials that exist now or could be reliable enough for building use by construction time. They can’t use graphene tension members or plasma windows or things that won’t even be invented for decades. Whatever they do, the materials and techniques will not remain state of the art for long. That means there is even more importance in making something that looks impressive. Technology dates quickly, style lasts much longer. So for possibly the first time ever, I’d recommend going for impressive style over substance.

There is an alternative; to go for a design that is adaptable, that can change as technology permits. That is not without penalty though, because making something that has to be adaptive restricts the design options.

I discussed plasma glass in: https://timeguide.wordpress.com/2013/11/01/will-plasma-be-the-new-glass/

I don’t really know if it will be feasible, but it might be.

Carbon foam could be made less dense than air, or even helium for that matter, so could make buildings with sections that float (a bit like the city in the game Bioshock Infinite).

Dynamic magnetic levitation could allow features that hover or move about. Again, this would need ultra-reliable electronics or else things would be falling on people. Lightweight graphene or carbon nanotube composite panels would provide both structural strength and the means to conduct the electricity to make the magnetic fields.

Light emission will remain an important feature. We already see some superb uses of lighting, but as the technology to produce light continues to improve, we will see ever more interesting and powerful effects. LEDs and lasers dominate today, and holograms are starting to develop again, but none of these existed until half a century ago. Even futurologists can only talk about things that exist at least in concept already, but many of the things that will dominate architecture in 50-100 years have probably not even been thought of yet. Obviously, I can’t list them. However, with a base level assumption that we will have at the very least free-floating panels and holograms floating around the building, and very likely various plasma constructions too, the far future building will be potentially very visually stimulating.

It will therefore be hard for Google to make a building today that would hold its own against what we can build in 50 or 100 years. Hard, but not impossible. Some of the most impressive structures in the world were built hundreds or even thousands of years ago.

A lighter form of adaptability is to use augmented reality. Buildings could have avatars just as people can. This is where the Google dream building could potentially become an architectural nightmare if they make another glass-style error.

A building might emit a 3D digital aura designed by its owners, or the user might have one superimposed by a third-party digital architecture service, based on their own architectural preferences, or digital architectural overlays could be hijacked by marketers or state services as just another platform to advertise. Clearly, this form of adaptation cannot easily be guaranteed to stay in the control of the building owners.

On the other hand, this one is for Google. Google and advertising are well acquainted. Maybe they could use their entire building surface as a huge personalised augmented reality advertising banner. They will know by image search who all the passers-by are, will know all aspects of their lives, and can customize ads to their desires as they walk past.

So the nightmare for the new Google building is not that the building will be boring, but that it is invisible, replaced by a personalized building-sized advertisement.

 

Will plasma be the new glass?

Now and again, everyone gets a chance to show the true depths of their ignorance, and I suspect this is my chance, but you know what? I don’t really care. I have some good ideas as well as dumb ones, and sometimes it is too hard to know which is which. I freely admit that my physics is very rusty. However….

Plasma is essentially a highly ionised gas; lots of ions and free electrons. It conducts electricity so is ideally suited to magnetic confinement. You make a current in it, and use magnetic field interaction with that current to hold it in place.It can also hold a decent charge overall, positive or negative. That means it interacts electrostatically as well as magnetically. Electromagnetics is all one big happy field anyway.

A strong magnetic field can be made that encompasses the plasma magnetically without it needing to be surrounded by a solid object. Let’s do a thought experiment.

Start off with a sealed ball and make a small hole in it, put an electric coil around the hole, send some current through it, and make a field around that hole to stop plasma escaping. Ditto the opposite side of the ball, so now you have a tube with plasma in it, albeit a fat tube with narrow ends. Gradually make the hole diameters bigger and bigger, and the tube shorter and less curvy. Eventually you will have more or less a fat disk of plasma. The relative dimensions of the disk will depend on the intensity and control of the magnetic field, the ionisation of the plasma and any currents you make in it.

With some good physics and engineering, adequate sensing and a decent control system, I reckon it should be possible to make reasonable sized disks of plasma. So, make two of them. Put the two disks reasonable close and face to face. Arrange them so that the electric currents in the plasmas run in different directions too. If they are both similarly charged overall they will repel electrostatically and their internal magnetic fields will also interact, but the managed applied magnetic fields could stop them deforming too much. Add more disks, and we have plasma plywood. Let’s call it plasma-ply for lack of a better word.

I can’t calculate how thin this plasma-ply could be made. I suspect that with future materials such as graphene and room temperature superconductors, future remote sensing and advanced computer control systems, they could be pretty damned good. If you try to deform one of these disks, it would resist, because the magnetic and electrical interactions would create force to keep it in place. We have another name for that. We call it a force field and we see them in every space opera. If the surrounding coils and other stuff is just a think ring, as you’d expect, you’d have a round window. Maybe a smallish window, but you could use a lot of the coils to make a big window in a honeycomb structure.

So we can bin the word plasma-ply and start using the words we already have. We will have force fields and plasma windows. Plasma will be the new glass, and an important 21st century building material.

3D printing the highest skyscraper? 600km tall structures may be feasible.

What would you do with a 600km high structure? That would be hundreds of times higher than the highest ever built so far. I think it is feasible. Here I will suggest super-light, super-strong building materials that can substitute for steel and concrete that can be grown up from the base using feasibly high pressures.

I recently proposed a biomimetic technique for printing graphene filaments to make carbon fur (- in this case, for my fictional carbon-obsessed super-heroine Carbon Girl. I am using the Carbon Trio as a nice fun way to illustrate a lot of genuine carbon-related concepts for both civil and military uses, since they could make a good story at some point. Don’t be put off by the fictional setting, the actual concepts are intended to be entirely feasible. Real science makes a better foundation for good science fiction. Anyway, this is the article on how to make carbon filaments, self-organised into fur, and hence her fur coat:)

http://carbondevices.com/2013/07/01/carbon-fur-biokleptic-warmth-and-protection/

Here is the only pic I’ve drawn so far of part of the filament print head face:

Many print heads would be spread out biomimetically over a scalable area as sparsely or densely as needed, just like fur follicles. A strong foundation with this print head on top could feasibly form the base of a very tall vertical column. If the concept as described in the fur link is adapted slightly to print the filaments into a graphene foam medium, (obviously pushed through the space between the follicles that produce the filaments) a very lightweight foam structure with long binding filaments of graphene graphene foam would result, that would essentially grow from the ground up. This could be very strong both in compression and tension, like a very fine-grained reinforced concrete, but with a tiny fraction of the weight. Given the amazing strength of graphene, it could be strong enough for our target 600km. Graphene foam is described here:

Could graphene foam be a future Helium substitute?

Extruding the supporting columns of a skyscraper from the ground up by hydraulically growing reinforced graphene foam would certainly be a challenging project. The highest hydraulic pressures today are around 1400 bar, 1.427 tonnes per sq cm. However, the density of graphene foam with graphene filament reinforcement could be set at any required density from below that of helium (for graphene spheres of 0.014mm with vacuum inside), to that of solid carbon if the spheres are just solid particles with no vacuum core. I haven’t yet calculated the maximum size of hollow graphene spheres that would be able to resist production pressures of 1400 bar. That would determine the overall density of the material and hence the maximum height achievable. However, even solid carbon columns only weigh 227g per metre height per sq cm of cross-section, so even that pressure would allow 6.3km tall solid columns to be hydraulically extruded. Lower densities of foam would give potentially large multiples of that.

This concrete substitute would be nowhere near as strong as basic graphene, but has the advantage that it could be grown.

(The overall listed strength of solid graphene theoretically allows up to 600km tall, which would take you well into space, perfect for launching satellites or space missions such as asteroid mining. But that is almost irrelevant, since graphene will also permit construction of the space elevator, and that solves that problem far better still. Still, space elevators would be very costly so maybe there is a place for super-tall ground-supported structures.)

But let’s look again at the pressures and densities. I think we can do a lot better than 6km. My own proposal a while back suggests how 30km tall structures could be built using graphene tube composite columns structures. I did think we’d be able to grow those.

Super-tall (30km) carbon structures (graphene and nanotube mesh)

We’d need higher pressures to extrude higher than 6km if we extruding solid columns, but these tube-based columns with graphene filament reinforced graphene foam packing would have a far lower density. The print heads in the above diagram were designed to make fur filaments but I think it is possible (though I haven’t yet done it) to redesign the print heads so that they could print the tubular structures needed for our columns. Tricky, but probably possible. The internal column structures are based on what nature uses to make trees, so are also nicely biomimetic. If we can redesign the print heads, then printing low density columns using a composite of filament reinforced foam, in between graphene tubes should work fine, up to heights well above the 30km I originally suggested. An outer low pressure foam layer can be added as the column emerges. It doesn’t have to withstand any significant pressure so can be as light as helium and add the strength needed to prevent column buckling. With the right structure, perhaps the whole 600km can be achieved that way. Certainly the figures look OK superficially, and there’s no hurry. It’s certainly worth more detailed study.

Super-tall (30km) carbon structures (graphene and nanotube mesh)

I recently blogged about a 200km moon-based structure. Here is my original earth-based concept, which could now be enhanced by filling columns with graphene foam

Could graphene foam be a future Helium substitute?

How about a 30km tall building? Using multilayered columns using rolled up or rippled graphene and nanotubes, in various patterned cross sections, it should be possible to make strong threads, ribbons and membranes, interwoven to make columns and arrange them into an extremely tall pyramid.

Super-tall structures for science and tourism

Think of a structure like the wood and bark of a tree, with the many tubular fine structures. Engineering can take the ideas nature gives us and optimise them using synthetic materials. Graphene and carbon nanotube will become routing architectural materials in due course. Many mesh designs and composites will be possible, and layering these to make threads, columns, cross members with various micro-structures will enable extremely strong columns to be made. If the outer layer is coated to withstand vacuum, then it will be possible to make the columns strong enough to withstand atmospheric pressure, but with an overall density the same as the surrounding air or less. Pressure is of course less of an issue higher up, so higher parts of the columns can therefore be lighter still.

We should be able to make zero weight structures in lower atmosphere, and still have atmospheric buoyancy supporting some of the weight as altitude increases.  Once buoyancy fails, the structure will have to be supported by the structure below, limiting the final achievable height.  Optimising the structures to give just enough strength at the various heights, with optimised mesh structure and maximal use of buoyancy, will enable the tallest possible structures. Very tall structures indeed could be made.

So, think of making such a structure, with three columns in a triangular cross-section meeting at 43 degrees at the top (this is the optimal angle for the strongest A frame in terms of load-bearing to weight ratio, though that is a simplistic calculation that ignores buoyancy effects, so it ‘needs more work’.

Making a wild guess, 30km tall structures may be feasible, but that is just a wild guess and I would welcome comments from any civil engineers or graphene architects. These would not be ideal for habitation, since most of the strength in the structure would be to support the upper parts of the structure itself and whatever platform loading is needed. The idea may be perfect for pressurised platforms at the top for scientific research, environmental monitoring, telescopes, space launches, tourism and so on. The extreme difference in temperature may have energy production uses too.

Getting the first 30km off the ground without needing any rocket fuel would greatly reduce space development costs, not to mention carbon and high altitude water emissions.

A simple addition to this would be to add balloons to the columns at various points to add extra buoyancy. I dare not try to calculate how much higher this would permit, but I suspect not all that much more since even with balloons, they cannot give much extra lift once the atmosphere is too thin.

Could graphene foam be a future Helium substitute?

I just did a back-of-the-envelope calculation to work out what size of sphere containing a vacuum would give the same average density as helium at room temperature, if the sphere is made of graphene, the new one-size-does-everthing-you-can-imagine wonder material.

Why? Well, the Yanks have just prototyped a big airship and it uses helium for buoyancy. http://www.dailymail.co.uk/sciencetech/article-2257201/The-astonishing-Aeroscraft–new-type-rigid-airship-thats-set-revolutionise-haulage-tourism–warfare.html

Helium weighs 0.164kg per cubic metre. Graphene sheet weighs only 0.77mg per square metre. Mind you, the data source was Wikipedia so don’t start a business based on this without checking! If you could make a sphere out of a single layer of graphene, and have a vacuum inside (graphene is allegedly impervious to gas) it would become less dense than helium at sizes above 0.014mm. Wow! That’s very small. I expected ping pong ball sizes when I started and knew that would never work because large thin spheres would be likely to collapse. 14 micron spheres are too small to see with the naked eye, not much bigger than skin cells, maybe they would work OK.

Confession time now. I have no idea whether a single layer of graphene is absolutely impervious to gas, it says so on some websites but it says a lot of things on some websites that are total nonsense.

The obvious downside even if it could work is that graphene is still very expensive, but everything is when is starts off. Imagine how much you could sell a plastic cup for to an Egyptian Pharaoh.

Helium is an endangered resource. We use it for party balloons and then it goes into the atmosphere and from there leaks into space. It is hard to replace, at least for the next few decades. If we could use common elements like carbon as a substitute that would be good news. Getting the cost of production down is just engineering and people are good at that when there is an incentive.

So in the future, maybe we could fill party balloons and blimps with graphene foam. You could make huge airships happily with it, that don’t need helium of hydrogen. 

Tiny particles that size readily behave as a fluid and can easily be pumped. You could make lighter-than-air building materials for ultra-tall skyscrapers, launch platforms, floating Avatar-style sky islands and so on.

You could also make small clusters of them to carry tiny payloads for espionage or terrorism. Floating invisibly tiny particles of clever electronics around has good and bad uses. You could distribute explosives with floating particles that congeal into whatever shape you want on whatever target you want using self-organisation and liberal use of EM fields. I don’t even have that sort of stuff on Halo. I’d better stop now before I start laughing evilly and muttering about taking over the world.