Maybe I'm crazy, but I don't know exactly what a slip ramp is?
What is it, and how does it differ from a normal freeway exit ramp?
No one has even bothered to make up write up a definition on Wiki yet. :-D
as far as I know, a slip ramp is a ramp between parallel sets of carriageways - for example, freeway main lanes to the frontage road, or vice versa. basically, you end up "slipping" over a few feet, but going in the same direction as before.
at least, that is how I have always used the term.
Quote from: agentsteel53 on November 25, 2011, 12:21:26 AM
as far as I know, a slip ramp is a ramp between parallel sets of carriageways - for example, freeway main lanes to the frontage road, or vice versa. basically, you end up "slipping" over a few feet, but going in the same direction as before.
at least, that is how I have always used the term.
That's how I've always understood the term as well. A good example are the ramps between the local and express lanes on the Dan Ryan Expressway.
The Pennsylvania Turnpike uses the term for an EZPass only ramp: http://www.paturnpike.com/newsletters/december00/page08.htm http://www.paturnpike.com/ConstructionProjects/Route29_SlipRamp/home.html
I've heard the term used for this (http://maps.google.com/maps?q=41.587154,-90.609956&ll=41.586724,-90.609811&spn=0.00459,0.006866&num=1&t=k&vpsrc=6&z=18) particular ramp. This falls (sort of) under the same lines as Jake's definition.
In Europe, I believe 'slip road' is used for entrance and exit ramps. The term isn't confined to expressways, either. The right-turn cutoff found at some stoplighted intersections (with a Yield sign instead of light) could also be called a slip.
Could be wrong, but check me out.
The term is used in the local traffic reports for the ramps between I-890 and its service road (for lack of a better term) in Rotterdam and Schenectady:
http://maps.google.com/maps?q=schenectady,+ny&hl=en&ll=42.81286,-73.971441&spn=0.009917,0.018153&sll=32.626653,-96.883621&sspn=0.364325,0.580902&vpsrc=6&hnear=Schenectady,+New+York&t=h&z=16 (http://maps.google.com/maps?q=schenectady,+ny&hl=en&ll=42.81286,-73.971441&spn=0.009917,0.018153&sll=32.626653,-96.883621&sspn=0.364325,0.580902&vpsrc=6&hnear=Schenectady,+New+York&t=h&z=16)
One of these ramps was damaged in the T.S. Irene flooding in August, and was closed for a time. Traffic reporters would say "and the slip-ramp to 890 in front of GE is still closed to traffic."
Jake's description of a slip ramp is exactly as how I would define them. When I think of a stereotypical example of it, I think of some of those on the Anacostia Freeway in D.C. (http://maps.google.com/?ll=38.906453,-76.939064&spn=0.001313,0.003259&t=h&z=19&vpsrc=6):
(https://www.aaroads.com/mid-atlantic/district_of_columbia/dc-295_sb_exit_008a_02.jpg)
A cursory Google search of 'slip road' returns results giving the same definition as 'entrance ramp' or 'exit ramp'.
Google searching for 'slip ramp', OTOH, returns more mixed results; some saying it's a local/express slip and others saying it's an entrance or exit ramp.
The DOT also describes the exit ramp from I-390 south to Brighton-Henrietta Town Line Rd as a slip ramp, even though the only difference between it and a regular exit is the lack of other ramps. It has more in common with the Pennsylvania Turnpike slip ramps than anything else posted here.
It seems like I'm the only one on here, but I've regularly heard and used the term to refer to a right turn at an intersection separated by an island of some sort from the intersection, like this example at Causeway and Washington Streets in Boston (http://maps.google.com/maps?q=Boston,+MA&hl=en&ll=42.367132,-71.058335&spn=0.001591,0.003433&sll=37.0625,-95.677068&sspn=54.928982,79.013672&vpsrc=6&hnear=Boston,+Suffolk,+Massachusetts&t=h&z=19&layer=c&cbll=42.367132,-71.058335&panoid=176w7-NfPvHNVtiyVd4dZg&cbp=12,294.04,,0,9.49).
The folks at the public works department in my hometown, back when I worked there, knew what I was referring to when I mentioned a slip lane, and that is also the term used in SimCity.
No, this was my understanding as well. Quoted by myself above: The right-turn cutoff found at some stoplighted intersections (with a Yield sign instead of light) could also be called a slip.
My understanding was that it was a connector between two freeways, that was full speed, at least that is what i think. For example exit 6 on the NJ Turnpike connecting it to the PA Extension is a slip ramp i think, allowing for a near full speed connection between two freeways.
Wow, I never realized there was so much confusion about this term. Myself, I've always known a slip ramp as a more or less lateral movement, such as from a freeway to its service road.
Some quick Googling might shed some light...
At least according to wikipedia, a slip lane is what me and kphoger were thinking of, while a slip ramp connects parallel carriageways on a freeway.
Quote from: deathtopumpkins on November 28, 2011, 11:09:03 AM
Some quick Googling might shed some light...
At least according to wikipedia, a slip lane is what me and kphoger were thinking of, while a slip ramp connects parallel carriageways on a freeway.
I remember the old version of the AAA map of Northern Virginia from the mid-1980s used the term "slip ramps" in the latter sense in reference to the ramps connecting the Dulles Toll Road and the Dulles Access Road. For those unfamiliar, it's a quad-carriageway with two carriageways in each direction; the inner (free) ones serve airport traffic and the outer (tolled) ones serve local traffic. Periodically there's a ramp from the Toll Road to the Access Road (westbound) or from the Access Road to the Toll Road (eastbound). The AAA map used to have the notation "Slip Ramps" with an arrow pointing at those spots.