AARoads Forum

National Boards => General Highway Talk => Topic started by: mrpablue on May 26, 2018, 01:09:07 AM

Title: Double Interchanges
Post by: mrpablue on May 26, 2018, 01:09:07 AM
I recently noticed that the I-10 / Texas SL375 stack east of El Paso also includes a full cloverleaf for the frontage roads. Is this a common thing in freeways with frontage roads, or is this interchange one of a kind?
Title: Re: Double Interchanges
Post by: wxfree on May 26, 2018, 11:55:09 AM
That's really neat.  I'd never noticed it.

It's just a four-level interchange because this layout actually saves a level because otherwise the frontage roads would need their own level to intersect.  This way each frontage road can share a level with its freeway.
Title: Re: Double Interchanges
Post by: SSR_317 on May 30, 2018, 01:13:33 PM
In case you were wondering, here's what it looks like: https://www.google.com/maps/@31.7013836,-106.2843639,959m/data=!3m1!1e3
Title: Re: Double Interchanges
Post by: cpzilliacus on May 30, 2018, 10:32:12 PM
In a sense, every interchange on the "dual" part of the New Jersey Turnpike (Exit 6 in the south to Exit 14 in the north) has a double interchange on the Turnpike side.
Title: Re: Double Interchanges
Post by: jp the roadgeek on May 31, 2018, 08:31:01 AM
There's a few instances of dual interchanges in CT on I-84 and I-91 involving the HOV lanes.  There are ramps leading directly to and from the HOV lane at the same point as the interchanges in the regular roadway. Granted, they are mostly partial interchanges, with exits heading north and east from Hartford, and entrances heading south and west to Hartford. They have come in handy a few times, especially when it's near Christmastime and I'm heading to the mall and I have a passenger in my car.  Saves up to 20 minutes sitting in the bottleneck coming off the regular exit.
Title: Re: Double Interchanges
Post by: mrpablue on May 31, 2018, 03:13:28 PM
Quote from: SSR_317 on May 30, 2018, 01:13:33 PM
In case you were wondering, here's what it looks like: https://www.google.com/maps/@31.7013836,-106.2843639,959m/data=!3m1!1e3
Sorry I didn't include the GSV  :-/
Title: Re: Double Interchanges
Post by: Roadsguy on June 01, 2018, 12:27:29 AM
The US 119/PA 43/PA 51 (https://goo.gl/maps/YyxxivszKz72) interchange is actually two separate interchanges at the same spot. You have the original diamond with PA 51, and the new semi-directional Y with PA 43 built on top of it.
Title: Re: Double Interchanges
Post by: Flint1979 on June 01, 2018, 01:38:17 AM
We don't have anything like that in Michigan. In Detroit for the most part the Service Drive (that's what they are called in Detroit) either ends or curves into the other highway's service drive. Like for example, you're going eastbound on the Edsel Ford Service Drive (I-94 is the Edsel Ford Freeway which is where the service drive gets it's name) and you are approaching the I-75 interchange on the service drive, the service drive just curves and picks up as the SB Chrysler Service Drive (I-75 is the Chrysler Freeway in this area). The NB Chrysler Service Drive ends at Ferry Street and the WB Edsel Ford Service Drive picks up from exit 215C which is posted as both Woodward Avenue and Brush Street. For I-94 Harper Avenue at times acts as the service drive too.
Title: Re: Double Interchanges
Post by: Bickendan on June 01, 2018, 05:40:53 AM
Quote from: Roadsguy on June 01, 2018, 12:27:29 AM
The US 119/PA 43/PA 51 (https://goo.gl/maps/YyxxivszKz72) interchange is actually two separate interchanges at the same spot. You have the original diamond with PA 51, and the new semi-directional Y with PA 43 built on top of it.
Along that vein, I-210/CA 210/CA 57/Lone Hll Ave https://www.google.com/maps/@34.1198317,-117.8273837,1372m/data=!3m1!1e3