I just got done watching Blade Runner for the first time. Really hated that movie. It did bring up one question for me though.

Is it even possible for us to create a city that is as huge, vertically, as LA was in that movie? The reason I ask is because it seems that the Earth would not contain enough resources such as steal and other metals to make more than a couple “metal” cities like that.

The first main structure that deckard flies into was several magnitudes larger than anything on the planet right now.

If we could build a city like that, using current building methods it would take 50 years just to finish one or 2 of those massive buildings.

So could we ever really do this?

(Im on my way over to Cafe to start a thread about the most over-rated movie of all time :rolleyes: )

Depends what we built it out of; Aluminium and iron are pretty abundant materials (and in the story, they have space travel, so they could be mining asteroids or something); more likely to be a problem (to us today, at least) would be the energy to refine and process the materials.

This movie is supposed to be set in 2019. We had better hurry up and get going if we are gonna look like that by then.

I am just wondering how long it would take, if it could be done, to build a city like that using current tech AND only use stuff found on earth right now.

It’s been my estimation that a lot of sci-fi authors are generally very overly-optimistic about their time estimations for future events…

I would wonder about the survivability of such a huge building in an LA earthquake. Smaller ones could flex in various ways to take the vibrations, but one huge block of a building would just have to hope for the best.

The world’s total production of steel is about 700 million tons per year. I don’t know how much steel it takes to build a structure, but if the average density of the structure is 0.5 grams/cm^3, with one year’s supply of steel you can build a structure one mile square and half a mile tall.

Actually 0.5 may be a conservative estimate of density. And there are other materials you can use.

Assume a generic room in a building is 20’ by 20’ by 10’ high, and has walls 1’ thick and a ceiling 2’ thick. That’s 2888 cubic feet of empty space in 4000 cubic feet, for a density 0.28 times the density of walls and ceiling, which, for the sake of argument, let’s say have 0.2 times the density of steel. Hence a generic building has a density about 5% that of steel. That is, you can build a volume of building 20 times, roughly, the volume of steel you have available.

The Earth’s crust is 5% iron, roughly. That is, 1/20 of the Earth’s crust can be turned into steel, roughly. Putting this figure together with that in the previous paragraph, we conclude that by using all of the steel in the Earth’s crust, you could build buildings with a total volume just about equal to the Earth’s crust. Let’s assume you don’t build on the oceans (70% of the land area). Then you could cover the land area with building to a height about 3 times the thickness of the crust, which is 3 miles, give or take.

Hence we conclude the ultimate iron resources of the Earth’s crust would suffice to cover the Earth in buildings 9 miles high.

On a more realistic level, we learn here that present iron ore reserves are estimated to be enough to produce over 230 billion tons of iron. At a density of 8 g/cm^3 that gives 2.9 trillion cubic meters of iron, or (from above) 58 cubic trillion meters of building. If the megabuildings are to be a mile high, there is enough iron known at present to build 14,000 square miles of them.

Either way, material resources have zip to do with whether you could build a `Blade Runner’ city.

As I recall, the buildings in the movie were said to be 400 stories tall. I’ve always assumed there were none taller.

That’s four times taller than anything that exists today, and moreover some of the buildings were slanted at a pretty steep angle.

They couldn’t support themselves with today’s technology.

Unless there was something inside them to decrease there weight. I’m thinking chambers filled with hydrogen or helium.

Have engineers ever experimented with this idea? Buildings would essentially be anchored dirigibles. Seems like it would work for tall buildings and also help to earthquake-proof them.

How about having big empty vacuum chambers?

Of course that presents the whole other problem of how to not have the walls of said chambers buckle under the pressure.

But what does “E.T.” have to do with the size of buildings in 2019?

I can understand throwing in the requirement concerning the abundance of raw materials, but why on Earth would you want to restrict it to today’s technology? If someone said no, we can’t build cities like that today, what would that prove? The story is supposed to take place in the future, when we have futuristic technology!

Unless they were cantilevered, say, 800 stories underground.

Yup. I’ll get working on the blueprints right away, sir.

Iron is the fourth most abundant element in the earth’s crust, about 5% of its total composition. Granted, not all of that is going to be recoverable, but the recoverable iron is easily in the hundreds of billions of tons.

The U.S., by itself, produces seven million metric tons of steel per month. The steel frame of the Empire State Building only weighs 60 thousand tons.

We could probably build thousands of 100-story skyscrapers without making iron scarce, even relatively.

I don’t know how you got that idea. It may have been bigger, but several orders of magnitude bigger is ridiculous. If a 100 story building was one order of magnitude bigger, it would be a 1000 story building.

The buildings in BR look big, but even the sprawling Tyrell pyramid proves smaller than it looks as the camera gets closer and we can make out a ceiling fan spinning in a room. Suddenly the perspective becomes “yeah, it’s big, but it’s not ludicrously huge.”

You massively underestimate modern construction. The Empire State Building was built over 70 years ago and is the tallest building in NYC. It took one year and forty-five days to build.

Sure. Hell, we could still do it by the movie’s date of 2019 if we put our backs into it. I hope we don’t, though. A few skyscrapers can be inspiring. A forest of them is a nightmare. LA has plenty already.

A problem with buildings of that size… the elevators. The solution they came up with for the twin towers was to have express elevators on the first floor that went up to particular where the rider would have to switch to the local elevator. Would this work on something of this scale or would they have to come up with a new solution?

I should have mentioned that the problem with the elevators is that the number needed to move the amount of people involved would take up so much space as to make the whole idea of gigantic building impractical.

Quick note, I don’t recall any building being specifically mentioned in the film as taller than Deckard’s apartment building. He lived on the 90-somethingth floor and there’s no compelling reason to believe the building was much taller than that.

That’s tall, but not even as tall as the WTC.

Regarding Orders of Magnitude:

The CN Tower, IIRC is the tallest building in the world, coming in at about 1,800 feet. One order of magnitude taller than that would be 18,000 feet (a little less than 3.5 miles). I don’t think anything in BR was even hinted at as being that high, much less 180,000 feet (two orders of magnitude taller, AKA 35 miles).

I’ve heard that. The OP wanted to know if we’d have to strip mine the whole earth for the materials, and if it was possible to build that many big buildings and so forth, which I answered above.

Whether or not super tall buildings could be made practical, who knows? In the film, they had flying cars, and, we can assume, flying busses. Elevators are not nearly as big a problem if you can deliver your workforce right to their home floor.

And then there are arcologies, buildings built to house the people who also work in them. Oath of Fealty, by Larry Niven and Jerry Pournelle, describes such an endeavor (which, coincidentally, also takes place in Los Angeles). You don’t have to move people very far if they work in the same building they live in, particularly if you intersperse commercial and residential sections so that people aren’t all trying to get to the same place from a single floor.

Guess you haven’t seen the New version of ET!!!

The reason I say that those buildings were so massive is because IIRC you couldn’t see the ground in any of the aerial scenes. That makes for some pretty massive buildings.

It’s been a while since I’ve seen the movie, but isn’t the existence of off-world mining colonies stated? I mean, isn’t that where the replicants escaped from?