Yes, differences in the bottom level of footings is common.

Single story buildings are more likely to have similar footing all around as they are supporting similar loads. As the height and weight of the building above ground increases you are more likely to see changes in the depth of the footing.

Another commenter mentioned that the depth of the footing is due to weight bearing. While this is a factor, it isn’t significant until the footing gets quite deep in comparison to the footings other dimensions. Mostly the depth of the footing is to either increase the overall mass/ weight of the footing or to keep the concrete from cracking and splitting under the weight.

Most high rises are built to stand for 150 years. The oldest ones have hit that point and look like they can easily go for another 100 years with regular maintenance. But, most only seem to last for about 50–70 years before they are torn down and rebuilt with new high rises due to the value of the land they are built upon.

If these are the only criteria, then yes.

Basketball fans have expressed an increased need.

On the other hand, medical use is on the decline. Assuming that medical needs had already been met at level not requiring a new hospital there is no additional need for a hospital if medical needs are decreasing.

The problem is that we have to assume that nominal needs were being met before this argument was made. If needs were unbalanced prior to this everything changes, but we haven’t been supplied this information.

Now if we go the other direction.

Is a basketball court a need? No. Therefore, has it actually negatively affected the basketball fans by not building the court. No, as it is more of a want than a need as described.

Should a hospital be built when there are fewer sick people? Hospitals are massive complexes requiring many many support businesses and personnel to operate at a massive expense. We have no knowledge if another hospital is near by, if the medical needs of the area are already being satisfied, or if a new hospital would attract economic resources from the greater community to support it.

Without knowledge of the surrounding area all we are left with is the statement that less people are getting sick. So, resources would be spent on a problem that already seems to be resolving. Even if you make the argument that by having more resources available you would be able to further push the rate of sick people down further; this assumes that there are people looking for medical aid and not receiving it. Again, this requires assumptions that are not supplied, and have no guarantee that they exist in this community.

So, at the end of the day. Build the basketball court.

The real answer has a lot less to do with physics and a lot more to do with politics.

The real answer involves lock to lock steering rations, friction coefficients of tires, downdrafts, and car weights. But cars are all different with different levels of drivers. Yes, different levels of drivers. If you can’t figure out how to parallel park why do you think you can take a high-speed maximum turn at a 100mph? And even if you can parallel park you can probably only do that turn if you have been professionally trained.

Most roads are speed defined either by traffic load or by turn speed. Typical streets are just classified as (highest to lowest) highway, arterial, collector, and street. Most municipalities just post a value based upon that designation.

Turns are more important when it comes to design speed.

The tightest turn expected to be taken by “composite passenger vehicle” is a 20-foot interior radius. And you need to be moving at about 2–3mph to make it. Think of a drive-through aisle with a u-turn. That would be a fair idea of the tightest possible turn.

On the other end we have freeways. Rumor has it that speeds of between 130–160mph were used to design the sharpest inside-most turns. Keep in mind that this is the freeway itself and not on or off ramps. In speaking with Caltrans engineers, they seem to feel that this is more of rumor that may have had some truth at one point, but now turns are more related to the realities of property acquisitions and whether the turns conform with general empirical models based on the existing freeway system.

In between these we have the posted speed turn. Again, most of this is based on empirical models released from Caltrans and the Federal Highway Administration, but the posted speed tends to be about half of the speed the turn is rated for unless the local municipality has decided to reduce it further. Again, don’t go thinking that this means you can take the turn at double the speed. You are more likely to lose control or spin your vehicle without a lot of training. And even that requires that your vehicle was set up correctly for a turn like that.

Please don’t speed through turns. You can easily kill yourself and others in a blink of an eye.

• Is it visually significant? Will it age well?
• Is it culturally significant? Is the designer aware of what it promotes, ignores, or ridicules?
• It will be a moment frozen in time. Does it look forward, to the past, or to the present?
• Who is commissioning this project? What do they stand for, represent, and how might this look to future generations?
• Does it represent a level of skill and craftsmanship that places it beyond the abilities of a layperson, a builder, a skilled professional?

The resin needs to be exterior rated and UV rated (they may not be the same thing).

Other than that it is application specific.

It would buckle under its own weight. Whether it broke into pieces would depend on the result of the buckling as it is very near the surface of the earth.

But, in broad terms how big would it need to be to support itself.

The circumference of the earth is between 24,859 – 24,901 miles. Let’s call it 24,900 miles and assume a path has been prepared so no issues with mountains or such. I believe that such a structure would act like a simply supported beam of half the circumference so 12,450 miles. Again assuming a steel static shape section like a box beam or wide flange we would have a 20:1 size for a nominal bridge load so it would need to be about 622 miles tall to support the weight and about 60 miles wide to support nominal torsion. So that covers half of low earth orbit.

We would need to place this thing higher than 3 feet off the ground as normal deflection of an object that big would be more than 3 feet as would the likely shift from the moon.

But in theory, you need a bridge roughly 620 miles high by 60 miles to hold a stable position. The further out it gets the bigger it gets.

Keep in mind that these are very rough design calls and the actual should be 10% or so smaller once worked out.

Houses have roofs design to shed water and snow easily with minimum maintenance over a long period of time.

Commercial buildings have roofs that also shed water, but are designed so that, when possible, to have annoyance equipment (loud, hot,…) placed on the roof if they are not needed within the building itself.

Firstly, keep in mind that bedrock isn’t solid rock as most people seem to think, but any form of soil and/or rock that has developed cohesive forces within its structure.

Secondly, you pretty much need tunnels to be going through bedrock otherwise you need to treat the soil as if it was a liquid.

Most of Los Angeles probably has bedrock between a couple of feet below the surface to about 20 feet deep. You are going to have pockets much deeper at valleys, beaches, or any other courseway.

In addition to the costs mentioned in other responses, there is the issue of the materials that make up the building. These materials have been altered and possibly ‘stored’ in conditions which may alter their attributes. In order to reuse these materials they need to be reassessed and possibly tested. When compared to the ease and cost of new reliable materials it commonly doesn’t make sense to reuse much of the existing materials in any other capacity.