Engineering Stack Exchange
Engineering Stack Exchange

Questions tagged [highway-engineering]

Highway engineering covers the design of highways, in particular: layout (vertical and horizontal), surfacing design and drainage

Highway engineering covers the design of highways, in particular:

  • layout (vertical and horizontal)
  • safety
  • surfacing design
  • drainage
53 questions
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What are the pros and cons of a traffic circle versus a traffic light intersection?

The debate of traffic circles (also called roundabouts or rotaries) versus traffic light intersections has been in progress for a while. Those in favor of traffic circles say that, among other things, that they are safer than traffic light…
APerson
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What is a Spiral Curve, and How is it Different from a Normal Curve?

I've heard the term spiral curve used to describe a section of highway that is more aesthetically pleasing to the driver's eye. However, I believe I've driven on enough road to say that I can't definitively tell the difference between any given…
gate_engineer
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Why was a coil chosen over a straight for this overbridge?

I saw this meme on Facebook showing a coiled railway overbridge and an alternative plan. I replied that straightening that overbridge will force it to start at the other side of the road, and you need to build a u-turn and there is a valuable…
Jesvin Jose
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Why do we pave roads instead of making them from removable parts?

If roads were made of removable parts, we'd probably have fiber cable internet everywhere by now I'd say. It'd be so much easier to install e.g. new electricity and water infrastructure and to maintain them if roads where made like that. We'd be…
Yuri Borges
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1 answer

Has a specific type of alternative intersection been shown to reduce congestion & accidents?

Localities in the US have different road layout and setups. For example the Michigan Left, Jersey Left/Jug Handle, vs a standard 4 way stop with left turns at the intersection. Have any of them come out as clear winners?
JedF
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What is the justification for working on such large stretches of road?

I live and work in the UK, a country known for relentless roadworks. Last week I drove through roadworks on the M1 that lasted for 18 miles, necessitating road users driving at 50 mph. Of course, almost all of this impressive stretch was simply…
Phil
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How are earthfills not eroded before they are overgrown with grass?

Almost every railroad and vehicle road landfill has its slopes overgrown with grass which is quite good at preventing erosion. However it takes some time (a year or more) for the grass to grow and emit enough roots to form a reliable mesh that would…
sharptooth
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Does passenger car traffic actually damage roads?

Pavement Design In roadway pavement design, the (US) controlling design load is usually the Equivalent Single Axle Load (ESAL). This number attempts to quantify how much bending stress a given vehicle causes in the pavement. Trucks have a much…
hazzey
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Best traffic control device/system for given situation

I am familiar with the round-a-bout/traffic light pros and cons, however, I've been tasked with deciding on a solution for the given parameters below. Currently, there is a two-way (four lane) road with a speed limit of 35 mph. Rough traffic counts…
Anthony Burleson
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1 answer

What are these banded earthworks near a freeway overpass for and what are they called?

The satellite view of this overpass (on Google Maps) shows some banded earthworks. When driving by, you can see that each band is an elongated triangular shape (street view): My guess is that these earthworks act as a wind break by making the…
CJ Dennis
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Effect on pavement by light tracked vehicles with rubber inserts

Is there data available to quantify the effect on pavement by light tracked vehicles with rubber inserts. One example of such a vehicle is the M113 armored personnel carriers shown below.
David
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Why are roads straightened when widened?

When widening a road, why does construction seem to inevitably include a "smoothing" out of the curves on the road, essentially making it more straight? I've seen this personally on roads where I travel, and you can even catch a glimpse on Google…
Will
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How are maximum speed limits determined for banked curves?

I was once told that the speed limits on banked highway curves (specifically off-ramps) were determined by assuming zero friction between the car and the road, such that as long as you stayed on the correct path of travel, the banking of the curve…
Ethan48
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How much noise does a road noise barrier block?

I am from The Netherlands, where noise barriers like these are commonly built along motorways: Now I live in England, where such structures are almost non-existent. In The Netherlands, living 200 metre from a motorway, I experienced far less noise…
gerrit
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How do you call the intersection with barrier and you can always right turn?

In the photo above I can name the first 3 intersection a) Regular intersection b) T intersection c) Skewed intersection I am having a hard time on identifying the fourth intersection, what do you call that one?
Cary Bondoc
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