I was looking at interchanges, as I typically do, and realized that the SPUI in downtown Tacoma is pretty...umm...tight:
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi.imgur.com%2FFEMrgPD.png&hash=71bafcfc74c8f8c46ae573809c291d58e3d3a3fa)
Normally, SPUIs, while compact in nature, tend to spread out a little from the freeway. The above SPUI, at least to my eye, seems rather tight in its design. It works well, but still seems pretty small.
Do you have any interchanges near you or others that you know of that are quite small compared to others of its type?
I don't expect a lot of replies to this, to be honest. Just a late-night idea.
I am aware that there has been a discussion about the tightest trumpet (https://www.aaroads.com/forum/index.php?topic=10898.msg259207#msg259207) already.
I can't think of anything for Albany off the top of my head, but Rochester has these: https://www.google.com/maps/@43.1423317,-77.5865126,297m/data=!3m1!1e3
To the left and right are two others that are even tighter. If I-490 were ever upgraded to modern standards, the NY 31 interchange here would probably have to be removed.
Someone should search for an old aerial of the US 60/KY 4 interchange on the east side of Lexington. It was an incredibly tight cloverleaf that was replaced with a SPUI.
I-55 at IL-53 in Bolingbrook (https://www.google.com/maps/@41.6846675,-88.0680149,810m/data=!3m1!1e3?hl=en)
I-57 at IL-17 in Kankakee (https://www.google.com/maps/@41.1185164,-87.835787,817m/data=!3m1!1e3?hl=en)
US 190 / US 67 cloverleaf in Baton Rouge:
https://www.google.com/maps/@30.5086004,-91.1716611,499m/data=!3m1!1e3 (https://www.google.com/maps/@30.5086004,-91.1716611,499m/data=!3m1!1e3)
Is the Four-Level in Los Angeles basically the tightest stack in the world? (The stack design, after all, was chosen there to actually conserve right of way over a typical cloverleaf of that time)
Tons of tight cloverleaf interchanges along the San Bernardino Freeway just east of Los Angeles, too.
Quote from: Alex4897 on June 28, 2014, 09:11:37 PM
US 190 / US 67 cloverleaf in Baton Rouge:
https://www.google.com/maps/@30.5086004,-91.1716611,499m/data=!3m1!1e3 (https://www.google.com/maps/@30.5086004,-91.1716611,499m/data=!3m1!1e3)
I refuse to classify that as a cloverleaf. Maybe a "butterfly" would be better since the ramps all look like wings on a butterfly.
Quote from: TheStranger on June 28, 2014, 09:20:29 PM
Is the Four-Level in Los Angeles basically the tightest stack in the world? (The stack design, after all, was chosen there to actually conserve right of way over a typical cloverleaf of that time)
Tons of tight cloverleaf interchanges along the San Bernardino Freeway just east of Los Angeles, too.
Those cloverleafs are what popped into my head after Alex4847's post (https://www.aaroads.com/forum/index.php?topic=12780.msg308785#msg308785).
Regarding the Stack along the Hollywood Freeway, I would say certainly top 5. There's one stack in Shanghai that might qualify as top 5 too:
(https://c1.staticflickr.com/9/8205/8288204116_4e79ed3f57_z.jpg)
Quote from: vdeane on June 28, 2014, 05:51:20 AM
I can't think of anything for Albany off the top of my head, but Rochester has these: https://www.google.com/maps/@43.1423317,-77.5865126,297m/data=!3m1!1e3
To the left and right are two others that are even tighter. If I-490 were ever upgraded to modern standards, the NY 31 interchange here would probably have to be removed.
I can't imagine a diamond interchange being any tighter than those.
Exit 31 off US 50 EB near the Bay Bridge in Maryland is a right turn across a frontage road:
https://www.google.com/maps?ll=39.02213,-76.422304&spn=0.000004,0.00327&t=m&z=19&layer=c&cbll=39.022163,-76.422943&panoid=NJeWe_r8yVn6ZMid1sLLMQ&cbp=12,127.7,,0,4.84 (https://www.google.com/maps?ll=39.02213,-76.422304&spn=0.000004,0.00327&t=m&z=19&layer=c&cbll=39.022163,-76.422943&panoid=NJeWe_r8yVn6ZMid1sLLMQ&cbp=12,127.7,,0,4.84)
Quote from: jake on June 29, 2014, 12:49:47 AM
There's one stack in Shanghai that might qualify as top 5 too:
(https://c1.staticflickr.com/9/8205/8288204116_4e79ed3f57_z.jpg)
I like that the ramps in the Shanghai stack open up into 2 lanes after the gore and immediately narrow back to one lane. Why even bother?
Quote from: Roadrunner75 on June 29, 2014, 01:39:39 AM
Quote from: jake on June 29, 2014, 12:49:47 AM
There's one stack in Shanghai that might qualify as top 5 too:
I like that the ramps in the Shanghai stack open up into 2 lanes after the gore and immediately narrow back to one lane. Why even bother?
Tiny ovetaking lanes seems to be a theme in other countries. I saw similarly-short overtaking lanes on slip ramps in the UK. They're pretty short but are useful if you're in a rush! :D
Quote from: jake on June 29, 2014, 01:54:32 AM
Quote from: Roadrunner75 on June 29, 2014, 01:39:39 AM
Quote from: jake on June 29, 2014, 12:49:47 AM
There's one stack in Shanghai that might qualify as top 5 too:
I like that the ramps in the Shanghai stack open up into 2 lanes after the gore and immediately narrow back to one lane. Why even bother?
Tiny ovetaking lanes seems to be a theme in other countries. I saw similarly-short overtaking lanes on slip ramps in the UK. They're pretty short but are useful if you're in a rush! :D
In some areas, they seem to cause more problems than they're worth. Knowing Chicago drivers, they'd have backups on all of these ramps during rush hour due to the short overtaking areas. :banghead:
Quote from: jake on June 29, 2014, 12:49:47 AM
Those cloverleafs are what popped into my head after Alex4847's post (https://www.aaroads.com/forum/index.php?topic=12780.msg308785#msg308785).
Regarding the Stack along the Hollywood Freeway, I would say certainly top 5. There's one stack in Shanghai that might qualify as top 5 too:
Heck, the stack interchange on Yan'an & North-South elevated roads.
Quote from: jake on June 29, 2014, 12:49:47 AM
I can't imagine a diamond interchange being any tighter than those.
Here is one (https://www.google.es/maps/@42.1489695,-0.4263006,590m/data=!3m1!1e3) that is similarly tight.
Regarding the OP and Jake's example, it should be noted that one of the intended premises behind the SPUI is that it could fit in the tight right-of-way confines of an urban area (hence the U = Urban).
As for tight stack interchanges, the I-110/US 61/US 190 stack in Baton Rouge (https://maps.google.com/maps?ll=30.508442,-91.158371&spn=0.011351,0.022702&t=h&z=16) is pretty tight. From experience, the flyovers are posted with a suggested 35 MPH speed.
Quote from: froggie on June 29, 2014, 09:06:15 PM
Regarding the OP and Jake's example, it should be noted that one of the intended premises behind the SPUI is that it could fit in the tight right-of-way confines of an urban area (hence the U = Urban).
As for tight stack interchanges, the I-110/US 61/US 190 stack in Baton Rouge (https://maps.google.com/maps?ll=30.508442,-91.158371&spn=0.011351,0.022702&t=h&z=16) is pretty tight. From experience, the flyovers are posted with a suggested 35 MPH speed.
I would assume that the interchange being is such close proximity to Alex4847's interchange (https://www.aaroads.com/forum/index.php?topic=12780.msg308785#msg308785) is not a coincidence?