6

The answer is slightly more complex than what the OP proposes -- this is due to two factors: The interconnect must be fail safe -- i.e. if the interconnect circuit fails, the system must be able to detect this and report a problem to both highway and railroad maintenance crews. To this end, special supervised circuits are used, using two relays in opposite ...


5

Roads are usually designed using catenary curves. https://sketchup.engineeringtoolbox.com/catenery-curve-c_169.html Road curves are designed around vehicle velocities and they are not uniform. As vehicles approach a curve they tend to slow down and then accelerate out of the bend which means a non uniform curve is best suited to the purpose. This can be ...


5

Circular arcs are not used except in special situations, because the sudden change in curvature from a straight road to a circular arc would mean drivers had to quickly turn the steering wheel to the correct position to follow the circular arc, hold the wheel steady, and quickly turn back to straight at the end of the arc. There would also be problems if the ...


4

A round-a-bout introduces a disruption in any traffic, no matter which direction. In your case the only two "collision" directions - two left turns - are the least used ones, so traffic lights working in a preference program with induction loops on the two possible left turns, plus uncontrolled right turn lanes would be optimal. The crossing would stay in ...


3

What country? This is different between different countries. I can give the sequence in Poland, which is standard in most of EU. 180 seconds of Blinking Yellow. (Groups [**] with Yellow blink yellow, the rest remains off. If the controller was already in this mode, past duration is counted towards the 180 seconds.) All Yellow. Whichever groups don't have ...


3

In UK terminology, your separate turning lane would be called a "filter lane" ( see e.g. Collins dictionary definition). This definition doesn't mean that you can always turn in that lane, it means that this lane is exclusively for turning; traffic in it may or may not have to wait for a green light. I might therefore be tempted to call it a "crossroads ...


2

Often it's a lack of real estate for any other interchange. As the interchange is very narrow compared to a partial cloverleaf. The other option is then a diamond interchange. The diamond interchange is more economical because it doesn't need a particularly wide bridge (4-6 lanes depending on the traffic of the other road). The single point interchange ...


2

There are several of these near where I live (in the UK) but I've never heard the term "burger lanes" before. We don't seem to have a name for them - they just are! They serve the same basic function as a roundabout with a flyover bridge, except that all the roads are on the same level. The intersections of the burger lane and the roundabout are controlled ...


2

This is probably an example of a channelized intersection, where you have right turn bays that split from the main road just before the intersection: References: Individual Movement Treatments - FHWA


1

Clothoid? I recall hearing that some roadway curves are designed using the Clothoid Spiral AKA the Spiral of Cornu AKA https://en.wikipedia.org/wiki/Euler_spiral in which the (radius of) curvature varies linearly with arclength. Caveat: this is from ages ago (AKA grad school); YMMV.


1

There is another state the lights can be in: blinking yellow. Which means that the intersection is not being controlled and normal priority rules are in force. Going from off to all blinking does not change how you should behave on the intersection. Going from blinking yellow to solid yellow (longer than the normal 3 seconds) to red gives drivers enough ...


1

As you might well imagine, there is a metric f-ton (the technical term :-) ) of research covering both queuing theory and prioritization analysis. The correct, if unsatisfying answer to your title question is: there is never acase where two items have exactly equal priority, just as in American baseball there's never an exact tie between ball reaching ...


1

I think you don't understand how the switch can work if there is no place to put the lever in the middle of a street. The answer is simple: you only put the socket and every driver brings his own lever. This system is still used today when the electric drive malfunctions. Here's a video where it can be seen how it's done. We can see the driver putting the ...


1

I don't see why the simplest explanation isn't the best, i.e. manual switches. Freight trains used to have people on board whose entire job was to manually walk and throw switches. This would work just the same for trams. Also, trams don't usually travel at high speeds, to it wouldn't slow things down much at all to have someone walk to manually throw the ...


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