4 replies to this topic

[PEin2010]

I think i'm going a little cuckoo with the exams only 4 days away!

My question is: I know that stations in vertical curves are based on horizontal distances.

How about the stations in horizontal curves?

[Ambrug20]

I think i'm going a little cuckoo with the exams only 4 days away!

My question is: I know that stations in vertical curves are based on horizontal distances.

How about the stations in horizontal curves?

The previous explanation is pretty much answering the question. When you design roadway, the stations on the vertical alignment are always mach horizontal. For the purpose of the exam, you need to figure out what alignment calculations needs to be perform. Also remember the difference between sag and crest curve (they do different calculations for sight distance and curve length), pay attention to it.
Good luck

[StogieFL]

Stations are based on the HCL (the horizontal control line). Typically, the HCL is also the centerline of the road, but that isn't always the case. So when the HCL curves horizontally, the stations follow that curve.

Just kepp in mind that parallel lines do not have the same stationing coming of a curve. Parallel curves have different lenghths of curve thus the stationing changes. This is whay many times you will see an equation at the PT of the Curve. If an equation is introduced then the Vertical Curve must also have an equation.


Learn about Engineering
http://www.whatisengineering.net/

Edited by StogieFL, 14 September 2011 - 03:31 PM.

[Dexman PE]

^^^ That's why you set your stationing to follow the HCL, and when you have parallel lines you refer to them by Station/offset.