26

I am not sure about this particular design. But in public places, the benches are designed to provide temporary comfort but discourage using them as a vagrant or homeless hang out, hence designed subtle discomfort. Also, they have to be easy to scan by security cameras and not have hard-to-see corners easy to hide contraband material or even explosives! ...


18

This is very common misunderstanding. When we look a a road, we see few centimeters thick layer of bituminous surface, and we think about "the road" as "the asphalt/tarmac." It's not. When you look how a road is build (or rebuilt), you can see that "the road" is actually over half a meter (or more) deep, consists of layers of sand and gravel and has ...


15

Cold makes things shrink. Despite being buried — presumably below the frost line — both the ground outside the pipe and the water inside the pipe are much colder in winter than in summer. This causes the pipe segments to shrink, putting tension on the joints, and increasing the chances that a weak one will fail. By contrast, warm weather puts the ...


10

Benches are not usually engineered as such. They are being made by furniture designers, (landscape/interior) architects etc. Now generally these professions put a lot of work into making their items novel in some way (Even if that novelty feels stupid to you). Reason for this is that they are being selected that way from catalogs, trade magazines and display ...


8

You mean going back to cobblestone roads? Many sidewalks are often paved with pavers. One of the challenges is maintaining a level surface. Asphalt holds itself together like a sheet and a dip in the surface below will pull on the sides delaying the onset of potholes. while separate parts will start moving under the vibration and frost heaving. Once the ...


7

I think that there are a few things that you aren't considering. Subgrade Most roads have at least 12 in (300 mm) of compacted aggregate (rock) under the actual pavement. If the existing soil is very weak, then this depth of aggregate subbase can be increased. Sometimes the soil needs to be strengthened by mixing in cement. This means that just removing road ...


6

Keep drawing combinations. You forgot Østerås to Vestli, Østerås to Bergkrystallen, and every other combination of possible origin and destination. This breaks down in a hurry. By the time you split up all the trains to hit every destination, you end up with only a few trains a day going where you want to go. Since you don't want to travel then, you ...


6

The main reason is economics. Who is going to pay for all the additional lines? The other part to this is, will the additional lines have enough passengers to make them profitable and sustainable? If the lines are on the Earth's surface how much land will they occupy and could the land be better used for something else? If the lines are underground, or ...


5

Q1: Yes. Q2: Yes. Q3: It depends but generally not much. Q4: No. Without getting into the technical details of how you recover the energy, consider it from a conservation of energy perspective. Yes, you can generate energy from roadways or stairs in a number of ways, but that energy has to come from somewhere. If you make the road generate energy from ...


4

As some of the other posters have mentioned a road has several built up layers (hopefully). The drainage system is usually very important. Bad quality roads are usually because the drainage is poor or non-existent. Roman roads were sometimes as much as 10 feet thick, which is why many are still in use today, 2000 years later. It is possible to create a ...


4

Water main failures are greater in the winter months than in the spring or summer. As a water utility professional in northern Illinois we have around 120 failures each year with 20 + years of data. Each and every year we have 90 of the 120 between December and March (Fact). The question that indeed is hard to define is why? Here are the facts I see year ...


4

In the bench that you show, the slats are supported and held in alignment by the end brackets. The armrests are supported by, and in line with, the legs. You could incorporate the end brackets into the leg structure but this would make for a more complicated moulding that either doesn't allow the same mixture of materials or has too many holes drilled in it ...


3

The reality of generating electricity from nuclear fusion on an industrial scale is still a very long ways off. It is speculative high cost, high risk venture, with a potential high payoff far off into the future. Test reactors alone are >$100 million. The existing technical problems and challenges with nuclear fusion are very complex. We're talking ...


3

On the following roads, a curb is not desirable - highway without pedestrian traffic, rural highway (ease of pulling to the shoulder and not to restrict water flow to ditches), City streets designated as walking zone, usually for tourism/commercial purposes, and no vehicular traffic allowed. The street curbs, raised sidewalks are designed to impede the ...


3

Here are some pylons in Norilsk, Northern Siberia, where temperatures get down towards -50°C (source) It's all a question of design and engineering: pylon spacing, the range of max and min ambient temperatures, and the range of currents carried on the cables - there will be whole design manuals that cover this, so a full answer would be way too long ...


3

Other answers have well described a road is a lot more than just the surface layer and the vast majority of the cost is the planning and logistics involved rather than the actual materials. Current road building materials are generally pretty much as cheap as engineering materials get, indeed many are effectively waste products from other industries. ...


3

There's nothing like kicking the dirt. I would advise actively participating in a manhole inspection, at least once so you know what it like. Do an inspection with an experienced person. By doing so you will have first hand experience of what is involved and what can and can't be easily seen or done via such inspections. Doing more such inspections would be ...


2

As far as I know, there are two major factors, fatigue loading and low temperatures. Pipes buried below roads experience fatigue loading from traffic, surprisingly enough. Literally cars driving over the road surface imparts a load onto the pipes, even if it's a very small load. However, this happens many times every day and pipes stay in the ground for ...


2

Pressure sensor that triggers alarm if something less than 1 ton but more than 10kg enters the garage. Electrify the floor, anyone walking in will be fried without a Faraday's cage protection. Fill whole garage with carbon monoxide fumes after entering. Suck out the fumes after 5min.


2

Dual gates, with the outer one always closing before the inner one opens. For extra security, a computer vision system could check that no people are present in the intermediate space before opening the inner gate.


2

It is difficult to provide a useful answer to this question without additional information. For example, what is the system pressurization - operating psi/bars? Having installed ductile iron water mains, and having pressure tested new installations to destruction (resulting from hairline cracks in new pipes), I can confirm that the effects can potentially ...


2

The problem with older and under-maintained (this is South Africa after all) systems is that the pipes get brittle, rusted and joints fragile and the network won't be able to handle the transient forces of constantly opening and closing valves, even if it's done slowly. The networks are in general not designed to withstand such large constant cyclic loading ...


2

Here is another thought. Have you had your arm on the armrest and someone walked by with a bag or otherwise just carelessly bumped into or smashed your arm? It might be nice to have a little of the bench sticking out to make passersby not cut in so close. I guess spikes like they put on chariot wheels might be more effective, but this design looks nicer.


2

Fusion is widely extolled by advocates as being safe (but is that collective opinion justified)? I would prefer to begin my discussion comparing fusion with renewable energy systems with an examination of safety as in my opinion, safety should always come first when we compare energy alternatives. Some Reasons offered why Fusion should be Safe - - Only ...


2

Laterally circumnavigating problematic bedrock is not always possible or practical for the following reasons: This can increase the length and cost of the tunnel The problematic geologic zone may be too vast laterally Such an alignment may already be minimizing the impact of a problematic zone by targeting the best geological zone available. As to the ...


1

Given that the six parallel lines in the centre of town actually consist of only two tracks (one eastbound and one westbound) running through "the tunnel" (Oslo T-bane or Oslo Tunnelbane) and that points or switches exist at the appropriate points (which they must to allow the existing route options) then your idea is possible. Figure 1. Stortinget station, ...


1

Best guess to the problem of adding more: Logistics and economics. First of all, never underestimate the cost of public construction project such as tunnel buldinnstuff. The last sizeable expansion was the Løren-banen which was finished a couple of years ago. The short stretch between Sinsen and Økern ended up costing more than 1 billion NOK (Google, 2018). ...


1

Since cost is not an issue how about an armed guard. Not every problem is an engineering problem.


1

You can install a passive solution like a Cattle Grid for people that would heavily discourage anyone from trying to walk on it. But then you might have to deal with the idiots that might get stuck and/or break they legs trying to cross one. Another passive solution is a ditch with about 6 inches of water, because I don't think anyone would want to soak ...


1

To begin with, gas/petrol filling stations may or may not be located at one site for a long period of time. Dealing with a disused pipeline for a closed station will be a problem. Continually extending the pipeline network will cause disruptions. One of the main issues, is like water distribution pipelines, pipelines for oil/petroleum products can burst, ...


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