A few years ago, as part of the add-a-lane project, a full cloverleaf interchange between Route 128 and Route 9 in Wellesley, MA where I live was turned into a partial cloverleaf with signalized left turns.
https://www.google.com/maps/@42.3168509,-71.2351492,507m/data=!3m1!1e3
As I look at it, I can't help but think that there's enough space to add left turn flyovers, especially as there's currently two left turn lanes and if it was grade separated, they could probably do with one, creating a Tight Urban Cloverstack, if you will. Are there any examples of this? And to be clear, I'm talking about arterial to freeway interchanges, not freeway to freeway interchanges.
Quote from: kernals12 on December 28, 2020, 09:22:09 AM
A few years ago, as part of the add-a-lane project, a full cloverleaf interchange between Route 128 and Route 9 in Wellesley, MA where I live was turned into a partial cloverleaf with signalized left turns.
https://www.google.com/maps/search/benihana/@42.3166356,-71.2353052,499m/data=!3m1!1e3
As I look at it, I can't help but think that there's enough space to add left turn flyovers, creating a Tight Urban Cloverstack, if you will. Are there any examples of this? And to be clear, I'm talking about arterial to freeway interchanges, not freeway to freeway interchanges.
Your google maps link took me to some japanese restaurant (https://imgur.com/a/AbqPAUR) not far away from me, not to some interchange in Boston
Quote from: SkyPesos on December 28, 2020, 10:32:53 AM
Quote from: kernals12 on December 28, 2020, 09:22:09 AM
A few years ago, as part of the add-a-lane project, a full cloverleaf interchange between Route 128 and Route 9 in Wellesley, MA where I live was turned into a partial cloverleaf with signalized left turns.
https://www.google.com/maps/search/benihana/@42.3166356,-71.2353052,499m/data=!3m1!1e3
As I look at it, I can't help but think that there's enough space to add left turn flyovers, creating a Tight Urban Cloverstack, if you will. Are there any examples of this? And to be clear, I'm talking about arterial to freeway interchanges, not freeway to freeway interchanges.
Your google maps link took me to some japanese restaurant (https://imgur.com/a/AbqPAUR) not far away from me, not to some interchange in Boston
It works for me. There is a listing of businesses to the left that can be ignored, but the location of the map is where it should be.
This interchange (https://goo.gl/maps/63xUqXPJwZsLC7uX8) in Indianapolis is close, although it's rotated the wrong direction (the flyover-left turn is along the freeway rather than the arterial).
This interchange (https://goo.gl/maps/A731VGxYDYVabBcs6) just outside of Disney World is probably more towards what you're looking for.
Quote from: pianocello on December 28, 2020, 10:48:55 AM
This interchange (https://goo.gl/maps/63xUqXPJwZsLC7uX8) in Indianapolis is close, although it's rotated the wrong direction (the flyover-left turn is along the freeway rather than the arterial).
This interchange (https://goo.gl/maps/A731VGxYDYVabBcs6) just outside of Disney World is probably more towards what you're looking for.
Actually, the one in Indianapolis is closer. The one in Florida only has 5 ramps so it's not free flowing.
There's this one in Memphis (https://www.google.com/maps/@35.0787448,-90.0565527,705m/data=!3m1!1e3), which has a proper cloverstack-looking flyover instead some more modest grade-separated ramps with left-hand entrances or exits. It was built like this originally, not added onto, and it's missing the complementary flyover because demand is very low in that direction. It's also pretty old, from the early sixties.
I'd like to say, these flyover ones are extremely like Cloverstack Interchanges ( https://en.wikipedia.org/wiki/Interchange_(road)#Cloverstack_interchange ), just one thing I'd like to say
The east half of this interchange in West Valley City, Utah (https://www.google.com/maps/@40.6969661,-111.9523243,841m/data=!3m1!1e3) is free flowing and might be similar to what you're going for
Quote from: US 89 on December 31, 2020, 07:45:22 PM
The east half of this interchange in West Valley City, Utah (https://www.google.com/maps/@40.6969661,-111.9523243,841m/data=!3m1!1e3) is free flowing and might be similar to what you're going for
Whoa, it's a diamond-cloverleaf-turbine hybrid interchange.
* They are not parclos, but the first three interchanges on I-80/I-94 after entering Indiana may be of interest: The interchanges with Calumet Avenue (https://goo.gl/maps/Vi5Y4RZP1juV5R5B7), Indianapolis Boulevard (https://goo.gl/maps/F5F4kcWCKgue7qmN8), and Kennedy Avenue (https://goo.gl/maps/LUQcSfbc9gcm4zWU8), are all high powered interchange with conventional roads with at least one flyover.
* The western US 60/ KY 4 - New Circle Road interchange on the west side of Lexington. (https://goo.gl/maps/4smopcLouV9uPyBK9)
I can think of several:
–OKC has one just north of the I-44/I-40 interchange near the fairgrounds.
–Part of the I-44/OK-66/OK-74 interchange also does this, but it also has a clover stack ramp.
–The interchange between Mercury Blvd and I-64 in Newport News is like this.
–I-4 and Maitland Blvd is another example, it was just redone with I-4 Ultimate.
However, I have to say, this type of interchange is very close to a clover stack, or cloverleafs with flyover ramps. However, clover stacks use high speed flyovers, where some of these examples seem to just be grade-separated left turns.
Quote from: MCRoads on January 04, 2021, 07:32:41 PM
I can think of several:
–OKC has one just north of the I-44/I-40 interchange near the fairgrounds.
–Part of the I-44/OK-66/OK-74 interchange also does this, but it also has a clover stack ramp.
–The interchange between Mercury Blvd and I-64 in Newport News is like this.
–I-4 and Maitland Blvd is another example, it was just redone with I-4 Ultimate.
However, I have to say, this type of interchange is very close to a clover stack, or cloverleafs with flyover ramps. However, clover stacks use high speed flyovers, where some of these examples seem to just be grade-separated left turns.
That's exactly what I'm looking for.
This is a very old thread, but this interchange may be of interest:
https://www.google.com/maps/@35.669554,140.0344407,328m/data=!3m1!1e3
This is the Makuhari IC (interchange), on Keiyo Road, an expressway outside of Tokyo.
Visually, it appears to be a partial cloverleaf B4 with the left turns using a flyover from the right side of the road. However, Japan drives on the left, so this is actually an A4 with free-flowing off-ramps. Traffic has a short distance (100 to 120 meters) to switch lanes with traffic on the arterial road before the exit for the loop back onto the expressway.
It was originally built like this back in the late 1960s. Things were much less cramped back then, but the process of expropriating land was just as hard back then as it is now (if not harder), so it is very compact:
(https://pbs.twimg.com/media/FJ6E5jjaAAEySns?format=jpg&name=large)
Edit: Modern view:
(https://www.photolibrary.jp/mhd8/img272/450-2012112722302838871.jpg)
^ Would I-395/VA 7 fit your description?
The I-8 to CA-67 interchange in El Cajon, CA is interesting. It has a flyover from EB I-8 to NB CA-67, but underneath it's a full cloverleaf because it originally connected to the old CA-67, which was Magnolia Ave. Following NB Magnolia now requires a pretty clumsy 360-degree loop through four traffic lights. SB has a big jog through two.
https://goo.gl/maps/9DP4ihzPc4pPoNPZ9 (https://goo.gl/maps/9DP4ihzPc4pPoNPZ9)
Quote from: pderocco on January 11, 2023, 01:18:22 AM
The I-8 to CA-67 interchange in El Cajon, CA is interesting. It has a flyover from EB I-8 to NB CA-67, but underneath it's a full cloverleaf because it originally connected to the old CA-67, which was Magnolia Ave. Following NB Magnolia now requires a pretty clumsy 360-degree loop through four traffic lights. SB has a big jog through two.
https://goo.gl/maps/9DP4ihzPc4pPoNPZ9 (https://goo.gl/maps/9DP4ihzPc4pPoNPZ9)
Seems in that case, with CA-67 being re-aligned onto the San Vicente Fwy, the need to follow Magnolia is quite dramatically reduced. Still, it is awkward if you're on Magnolia south of the 8, and want to continue specifically on Magnolia, it is indeed rather awkward.
SR 528 at SR 417 in Orlando, FL has a one ramp parclo ( if you call it that) but three left turn flyovers. That might be a systems in definition.
US 192 at I-4 near the soon to be dissolved Reedy Creek Improvement District in Osceola County, FL is one with two left turn flyovers but far from a systems exchange as really one flyover is a turbine ramp.