Types of Partial Cloverleaf Compared! - ParClo Interchange Comparison

Types of Partial Cloverleaf Compared! - ParClo Interchange Comparison

➤What has two loops and no weave? Nope. It's a Parclo! Many types of Partial Cloverleaf interchanges have been used all over the world to move traffic on and off the highway. This is a comparison between the effectiveness, advantages, and disadvantages of different configurations.

Steam Workshop Downloads:

0:00 Intro
0:31 Cloverleaf Problems
2:30 A2 Parclo
3:44 A4 Parclo
4:56 B2 Parclo
6:20 B4 Parclo
7:41 B4 Roundabout Parclo
8:49 AB2 Parclo
11:02 AB4 Parclo
12:01 In Summation

#citiesskylines #parclo #yumbltv

[MurcuryEntertainment]

I love that Cities:Skylines has achieved the unthinkable in many cases: a fantastic non-violent game that can genuinely educate and excite people about some really mundane but important subjects like intersection conflict points, zoning rights, noise pollution, economic drivers of cities, and where traffic really comes from.

[itherius]

Just a possible fun fact

But the A in A2 probably stands for "ante"
This is a latin word for "before" and is often used in older words like
AM: Ante Meridium (Before Noon)
Antechamber (self explanatory)

But also modern words such as:
"To anti-cipate"
or an "antecedent"


... maybe :P

[catmank]

I think in real life this AB2 is build, as it saves space, sometimes you have already buildings on one side of the road and from city planning, they might be both at the same side.

[beastateverythin]

AB2 is my exit off the highway in my hometown lol. It works fine because in my location traffic is very asymmetric. Most of civilization lives “south” of the exit (as you have it set up) and only a little bit is north. There’s a light at the southern intersection and there’s no light at the northern one

Edit: my mistake, yes there is a light at the northern intersection one but it’s almost alway green until someone sits waiting to get off the highway and turn left (north)

[arnejungclaus]

I think the ab2 would be acceptable if the arteriel is ending at that point (or there is at least heavely asymmetric traffic) and you have no space for diagonal opposed leaves.

[TheAutoBeef]

As to A4 and B4 with roundabouts, the volume of traffic is sort of swapping, so in the regular B4 (without roundabouts) the left turns accure from the "inside" of the arterial (on the bridge) and slow the traffic, but with a roundabout you give priority to the left turn, and slowing down traffic from the outside of the arterial.
i would even consider A4 with roundabout that for the same reasoning, act very similar to B4 without roundabout.

[jamestipler]

One way to remove pressure on the AB4 would be to remove the pinch point at the offramp. You have a single lane leaving the highway, splitting into two lanes where one turns right and one left when they hit the regular street. Obviously the left turn at that junction is the blocker, so if that was two lanes from the highway where traffic could chose if it was going left or right by getting in lane while still *on* the highway, then things trying to make a right turn wouldn't be sat behind things waiting for their opportunity to turn left. I'm not sure that the cim AI would understand the concept tho, and might just queue on the highway anyway.

[ayanda]

I've been quite sad and down lately and every time you upload I get to forget about the stuff that's going on in my life for 10-20 minutes. Thank you <3.

[MaxFX]

The numbers in A2, B2, AB2, A4, B4 or AB4 stand for the number of quadrants (with the highway and the arterial road dividing these quadrants) that have ramps in them, not the number of ramps themselves. I've also noticed I've got the chevrons on one junction of the Cloverleaf pointing the wrong way. I'll adjust!! :)

[joshb]

I just want to say that because of your videos on Parclos, and also the SPUI on another recent video, my cities look better, function better, and they are, again, thanks to your guidance, really quite easy to build. I do like the B4, I need to sit down and try the roundabout version though.

[mrxmry]

0:41 that is what i would call a modified cloverleaf, because the highway splits into 2 roads. one goes straight through while all the splitting, merging and weaving happens on the other one.
but you can't really compare this one with the other ones in this video because they don't have the same types of roads.

you can practically eliminate the weaving problem in a modified cloverleaf by switching the 2 lanes going into the side roads, using bridges. that way, the only weaving will occur when someone wants to do a 180 and go back the way they came. i built and tested one of them on the junction test map. i placed obstructions at thee exits from the cloverleaf, when it was all jammed up, i removed the obstructions and traffic flow was back to normal within minutes. the same test on the vanilla cloverleaf (not modified at all) and it did not recover. the cars kept blocking each other.

BTW, i just noticed that some of the chevrons point the wrong way. they should be pointing where the traffic is coming from.

[Lussimio]

In a rural situation, just plop down a roundabout and you're good to go! That's like the aproach Norway uses everywhere. The most complicated junction here is called 'Sinsenkrysset' and is a three level roundabout.

[Rionescu]

Great work as always! I loved seeing the in-game comparison of these interchanges that are so common in southern Ontario! Two things on the AB4:

1. In real life, the south intersection — if not both — would be signalized and traffic exiting to go northbound would likely not turn into that leftmost lane, eliminating the northbound weaving. Southbound weaving does remain an issue though.
2. In the same way that an A4 prioritizes traffic exiting the highway and B4 prioritizes traffic entering the highway, AB4 prioritizes traffic heading to and from the east, since all movements to and from that direction are via free-flow ramps. That's why that design might be used in real life, for example, at a suburban interchange where most traffic is headed to and from downtown.

[Excalibaard]

Love it!
I think you identified the difference between A4 and B4 correctly, B4 has 2 lanes entering and 1 lane exiting per intersection. A4 has 2 lanes exiting and 1 entering. The largest contributor to the preference is probably the road real estate difference between them, as the preferred direction can split its traffic over two lanes (slip lane and lane from other junction).

I've seen AB2s being used at less rural areas, but they often have a light, with multiple dedicated turning lanes just to allow traffic to wait without backing up into the intersection (so you'd have 3 lanes to turn right onto a 3 lane road for example). The AB2 is probably only good in the scenario where you can't build on one side of the road, or need smaller footprint (wider roads are easier than new roads). I've never seen an AB4 though.

[thejontao]

In terms of the AB2, if the highway is crossing a river and the road is parallel to said river, you might have no choice but to use an AB2.

There is an interchange in Portland, Oregon which does this and for this reason, I believe. Only it’s not a service interchange, it’s two highways…. But it’s the same idea in that the river forced design decisions. I think it’s where the 205 crosses the 14. I drove it once with my dad on a trip from Mexico to Canada. I grew up in a very rural part of the world… interchanges blow my mind.

Edit: corrected interchange type

[danielgr]

2:28 loved that giggle! 😂
Great video as always

[ZorenManray]

We used to have cloverleaf in this metro area but they were nearly all replaced by A4.

Also we do have several AB4 interchanges as well.. yeah they really don't work well sometimes..

[sarahs.]

Why did no one think "a = after" "b = before" lol

[RexConnors]

I love these comparison videos, super informative. Great format

[wifelikecow]

I've driven on what I'd think is a Parclo in Tennessee that was effectively an AB4, except both loops were on one side of the interchange. It had an arterial over the interstate with loops and slips on the southeast side of the interchange, or to your right if you were northbound on the highway. The opposite side just had ramps for on and off traffic. The leaves feed into a merge lane that comes off the main northbound lane and then re-merges after the northbound slip. Don't know how you'd classify it, but I'd say it worked, except for the fact that it was barely a mile up from a Flyover T that merged into I-40.