Actually, it's a major clusterfuck. There's so many problems with this, almost everything needs to be re-engineered. First of all, a decent interchange has four way direction - including coming back in the opposite direction (a way to make up for an earlier mistake). To keep up the speed, thus the efficiency, the elevation needs to be less than 2% and turns with less than a radius of 600 m for 120 km/h. Number of lanes also need to be increased in the interchange to keep up the speed. To make it all economically viable there needs to be buildings, parking lots, shopping center, restaurants and hotels in each quadrant. This is best done with a roundabout to connect it all which second as an alternative for they who are confused or not sure where to go and need to circles a couple of times before they choose. An intersection like this needs a capacity of 50x the speed limit in km/h to avoid jams on a day when the highways are 90% utilized. Finally, all acceleration and de-acceleration lanes need to be at least 30 seconds which translates into 800 meters for a 120 km/h highway. An interchange basically needs 10x the size of the speed limit - for 120 km/h it means 1.2 square km. Anything less and you will produce jams and poor economy.
That is so great!! Also idea: instead of layering roads in -12; 0; 12; 24m, you could layer them at -18; -6; 6; 18m. It would me more... symmetrical? And you can use shorter ramps, if you don't have much space.
My idea exactly! If I'm right now you have 0 and -12 main roads connecting to the +12 and +24 overpasses. Using -24 instead of +24 would make the maximal height difference lower. Then bump up everything +6 and you have full symmetry!
It'd also be way more realistic. 12m is almost 40 ft tall. 24m is close to 80ft. That's absurd considering most bridges don't eclipse 25ft of clearance. Even if that's the surface of the road, it's only 5 feet or so thick. 10 max
Please don't skip the Interchange marking part. I would really love to watch that part. I love how you create all the details and explain. Please continue this series with Interchange marking part. Thank you. Really appreciate your work. Great content. I subscribed to see more great works & detailed designs.
The most useful part of this video is learning how to make a stack interchange. But the second most valuable is absolutely learning about the Home button shortcut.
Made my very first stack interchange following this guide, thank you. Was a bit tricky since my highways aren't perpendicular but still managed to do it haha.
This is awesome. I’ve just finished making my own version of this. Had to adapt a bit because the 2 freeways weren’t intersecting on a 90° angle, but it worked out perfectly! Thanks a lot buddy
I plopped Yumbl's stack yesterday. With minor changes to account for my traffic bias it's working great. Looks good with all the markings done. Thank you Yumbl!
@@YUMBL Elevation and tunneling both drive costs up, I am sure that the way both are constructed has a lot to do with original and ongoing maintenance. I try and keep everything ground level as much as possible so I think my 4 levels would look a lot different in the interests of keeping cost down, but the 2 main roads would be in the trench and directly on the surface for sure, . Then the left turn ramps would be on dirt as long as possible. I am sure there is a sweet spot with dirt ramps too.
@@YUMBL Yeah I saw all that evelvation and kind of wondered. The Pinavia just looses I saw Czardus suffer through doing his monster and decided that was not for me. I do try an keep in mind this is just a game too. There is no way the kind of landscaping done in game would ever get planted between fire, collision and whatever other hazzards. Including the pruners, have you ever hired the guys that do the big trees? good Gawd!
Try doing this on console; it's much harder to do, we don't have any mods and far less vanilla options. To do what you did in the first 10 mins takes around 1 hr and when you know how to do it; around 30 mins. Still I love these videos because it really helps traffic flow👍
Thank you for this video. Took me a long time to get it right because I'm playing on Xbox. Ended up having to have both highways underground because the pillars kept clashing with the highways. It works so much better than the roundabout I originally used and now my traffic is up to 92%
I keep coming back to these for reference and I just realized you have the perfect place to put support pillar now. The junctions where the right and left turn ramps meet on the corners of the "cross." It gets the concrete pillars out of the way of out of control cars.... Probably preferred in real life too.
My city (Albuquerque) has one of these that is pretty much the same in basic components, but it's at an angle and has more lanes, so it looks extremely large and complex. It's called "The Big I" by locals.
Those Albuquerque freeways are actually beautiful with the Mexicali trim--lots of orange and sky blue on the sides of the overpasses and retaining walls. Makes a typical concrete jungle city into something aesthetically pleasing!
Actually this one only takes up less space in the plane/plain, but it needs a lot more space in the depth than a clover leaf. Basically you can build the whole clover leaf on ground level except for the center piece where the main directions cross, which is considerably less construction effort. Additionally, a clover leaf junction allows for going back in reverse, so you could easily come back to a junction you missed previuosly. Despite this, the stacked interchange might actually perform better, especially in the game environment.
Detailed guide. Thanks. Freeform works, curved road works too to get the big curved part. Maybe that will guarantee a 180 degrees. I usually go for +/-10m off ground, then 8m per stack, works most of the time.
For measuring the 45°, I would demolish the highways in the center except for the little 4*4 square, go out 14u perpemdicular from all the corners so you get a #, then connect the ends, then with grid snapping on you draw the 2u road parallel to the ~20u road centered on it's ~10u node, demolish the ~20u road, draw another 2u road in it's place, demolish the other 2u road, done. This is gonna be 2m off compared to the method shown in the video, also certainly not as easy or quick, but you don't need any mods for it. My 2 cents. Great tutorial btw, I was always afraid of building a stack interchange. With thar 4 levels it's pretty intimidating. So thank you!
Great idea! I’m a big proponent of using roads as “scaffolding” to measure and mark positions in any situation. Always use a template for heights as well. With mods you can build the whole intersection flat and determine heights later. Thank you for watching :)
The anxiety I get watching those sudden merges happening between two platoons of traffic up high on those flyovers..... Would definitely need two lanes coming down those ramps, but this is such a cool concept!
LA has the world's first stack Interchange, build in 1953 for the crossover of the SR-110 and the US-101. It's usually called "The Four-Level" in LA traffic broadcasting--though the type of interchange is named after one of its older nicknames, "The Stack." The turning lanes bow out a bit more before beginning the turn and pass closer together at the center, so it looks more like a flower from above than an iron cross, and actually has the straight-thrus on the top and lower-middle decks.
High marks for symmetry but the one suggestion I have is that you make the overhead ramps diverge a little farther away from the straight through routes. It's rare that they are that tight together, usually they'll curve out more before changing direction and crossing over head. That way you can fit more columns at more realistic spots.
And I built one of these too! (Did your SPUI last night). Once again Yumbl thanks for the tutorial, I have thought long and hard about it and finally come to the conclusion that building roads is my favourite thing to do, and your tutorials have helped enormously. I don't think anyone else on RU-vid is doing these interchange tutorials as well as you sir. Might I make a humble request though - could you do a quick video on the Y interchange, joining three highways together? I really struggle with those! Thanks again for all your efforts, makes me at least a happy Cities player.
A modification would be to have the crossovers occur about halfway between the point where the right hand turns branch off and where the two highways cross. Doing that allows you to bring all 4 left turns to a single point where all 4 left turns can take place simultaneously and only have a 3 layer stack.
Wonderful idea! That is actually called a Turbine. Ot requires a compound curve which is much more difficult than a stack in my opinion, but they look amazing. Thanks for watching!
@@YUMBL Actually, what I was thinking is slightly different than a turbine. The 4 left turns come together at a third layer of the stack that is set up like a SPUI except the off ramps from the highways cross over the on ramps so that traffic flow at the SPUI is UK style. That allows all four left turns at the SPUI to take place simultaneously.
@@YUMBL not exactly a roundabout per se. Yes, all traffic is flowing in a counterclockwise direction. But picture a standard intersection in the UK where they drive on the left. Cars at that intersection can all make left hand turns at the same time with out crossing traffic. Now make the “intersection” larger so it isn’t a 90 degree turn. That’s basically what I had in mind as the middle layer between the at grade highway and the elevated one.
You are amazing. I learn so mutch and i need somthing witch helps me to calm down from work. Thank you so mutch i is a pleasure to watch, and try by my self.😃😃😃
This is the nicest-looking, most compact stack I've ever seen. I'd put one in my city except we already have one and it intermixes local and express highways, effectively making it a 4-direction 8-way, if that makes sense. It's very wiggly and organic-looking, and I call it the Big Chungus because it's absolutely outrageous. Actually, I think tomorrow I should build a sanitized version of the Chungus in the editor (one that isn't trying to squeeze around historic city buildings). I could plop it into that interchange testing map and run all 8 highways through it. That would be fun to watch!
The most ingenious interchange is like the Rte. 8 and I-84 interchange in Waterbury CT, where you have all four directions stacked each having their own level, thereby reducing the horizontal footprint!
I do this kind of interchange sometimes. So I know this is an old video but there is one more thing. The flyover sliproads may need lane mathematics when they merge. And then converge again before merging into the highway.
Historic Reference: The first of these, completed in 1949, is in Downtown Los Angeles, and is known as the 4-Level Interchange. Due to integration with surrounding topography, the layers are unusual: The bottom layer is the NE/SW interchanges, the next is the N-S through lanes, next is the NW/SE interchanges, and the top is the E-W through lanes.
A) A pillar with cantilevers right in the middle of the whole thing would look really good I think. B) I think it looks a lot better with the lefts as the top two layers, but them being in the middle is more realistic C) what's it called when the lefts exit from the left side and merge from the left? Detroit has quite a few of those.
Very nice. Only issue is you have Level 1 crossing left at Level 4, creating a steeper incline than needed. I would make Level 1 left at Level 3. And Level 2 left at Level 4, to keep the inclines symmetrical in all directions.
Nice one, though I'd really have taken the time to turn the lower ramps into two lane highways for completeness' sake. What makes the stack so cool is that it's basically conflict-free. Adding yields on every corner creates four major conflicts. Also, concerning visuals , I always use Network Skins to remove the lane arrows and streetlights on my highways for extra realism. It just looks weird to have a highway or intersection in the middle of nowhere lit up like a Christmas tree. It also removes the nuisance of lamp posts clipping through the ramp above. 😉
Welcome to my mini-essay. Having the elevation difference at 12m is overkill. The interstate standards state that the minimum overpass clearance is 16ft (4.9m) [1], which is apparently only necessary due to national security concerns (for very tall military vehicles) [2]. Assuming that the base of a Cities: Skylines overpass is about 2m, that would make the actual minimum elevation difference 4.9m + 2m = 6.9m. Adding a bit for roundness and just in case, an 8m elevation difference is sensible. 12m is 1.5 times more than this. Having too high of an elevation difference introduces problems. Firstly, a taller overpass is more expensive, and requires longer slip lanes which are more expensive, but we can ignore the cost aspect for this analysis. The grade of the slip lanes is of more significance. The grade of the steepest slip lane as 8.57%, calculated by dividing the change in elevation (24m) by its horizontal length (35sq * 8m/sq = 280m). For context, on level terrain like in this situation, the interstate standards allow a maximum of 4% as the grade of the highway, up to 5% when in an urban area [1]. The subject is, however, a slip lane which has different specifications. The absolute maximum grade of a *compact* connector road is 10%, but the recommended maximum is 8% [3] (worded as "must not" vs. "should not"). If the slip lane in question was classified as compact, then it would be in violation of recommended guidelines. Compact grade-separated interchanges are distinguished from fully grade-separated interchanges by the condition that at least one of the roads is not free flowing [4], which is not the case here as a stack interchange is, by definition, free-flowing [5]. Furthermore, compact interchanges are not permitted on highways [3], making it clear that this situation must be fully grade-separated. For fully grade-separated interchanges, the maximum permitted grade for a slip lane is 6% [3], which is less than 8.57%, which means that your interchange is AGAINST SPECIFICATION and therefore must be PURGED IMMEDIATELY. 1: en.wikipedia.org/wiki/Interstate_Highway_standards 2: safety.fhwa.dot.gov/geometric/pubs/mitigationstrategies/chapter3/3_verticalclearance.cfm 3: www.standardsforhighways.co.uk/prod/attachments/871d6bff-0126-41b7-bf34-a05c7e74a52f 4: en.wikipedia.org/wiki/Grade_separation 5: en.wikipedia.org/wiki/Stack_interchange
I get what you want to say, but you are measuring from the low road to the bottom of the overpass. Cities skylines is not. The overpasses can be quite thick. Also this is an old video. I use 10m now.
You’re exactly right! About the efficiency, and node controller not being featured in the vid. Feels more like part of the detailing process, but some people would like to see that too. Thank you for watching!
Make space inbetween your main highways as they meet at the interchange so that your left hand turns can branch off the middle. This way left turning cars can stay in the left lane, cars continuing forward can stay in the center lane, and cars turning right can stay in the right lane. It gives the traffic better flow and is more logical.
For the people who wonder if this is possible on console: yes it is possible in this way. Just make sure one highway is underground and the other is on the ground so the pillars can be placed more easily
I would recommend adding a short section of two-lane road at each merge, for lane mathematics sake. It'll help it flow a little more naturally. EDIT: seconds later, the very thing i said is recommended in the video, lol.
>Your GPS will notice I can already imagine a GPS AI downloading itself into a Boston Dynamics robot, grabbing a 2x4 while escaping from there and then going to the civil engineers home address.
@@YUMBL I really dig aesthetics of your Cloverleaf interchange, but I kinda like using diamond one in game due to its compactness, I tried to do your cloverleaf but it felt so huge 😅. I can't wait to see whats gonna be next on your schedule :D
@@YUMBL I tried your Clover on a new game in first plot of land, when I was done I almost had no space to zone anything... I was like... "Yup, that ain't gonna cut it 😅" Il defo check your workshop builds :)
Not bad, but I would have the ramps go a bit further from the main highway. You had the ramps nearly at the edge of the main highway. If the ramps were further, then it would be easier to fit in pillars for the ramps. The design you showed in the video would work best in a city where a larger interchange would be more expensive due to land acquisition costs.
So you are excellent at this stuff and I want to do exactly what you do. My interchange game is embarrassing. One thing, though. I wish you wouldn't do so much off screen and actually explain that process too, even if you feel like it is redundant. For instance, all the terraforming you did to get the highway to sink... that entire part was totally cut out and that is what I need to most. Please help!! Explain next time!!
This video needs an update please! Much more helpful tools at your disposal and with the added updates in the node controller and the painted lines! Oh yes I cannot wait to see it! :D
"Please don't engineer a road, based on anything I'm saying" Aww, shucks, I was just about to go and build myself a stack interchange and the and of the road...
Would going underground help with the stack interchange to keep the height down? At least the crossing roads could have one go underground or in a valley to miss the other road, that would mean the cross over roads would only be two stacks above the 'ground level' since one would be in the 'basement'. This would, of course, raise the price a little and be an issue during any situations that allow flooding.
@@YUMBL you're real good at designing and building those in this game! don't take my comment as anything negative with what you're doing.. just reminded me of all the 1 lane flyovers i have been on and me thinking (as driving on them) how in the hell are they going to resurface these in 5 years without shutting down these connection points.. and what a mess that will be..
I was taking to a construction worker responsible for logistics. Its actually a nightmarish puzzle. Taking nature, traffic, laws, existing utilities etc into account. In cities i just have to draw roads. No problem at all, and welcome :)
I worry about how the merging would work with the right hand turns, seems dangerous to have them merge at that angle, but you can always just change the lane math a bit and it would be fine.
Edit: That was actually exactly what I needed to do, now it works fine. And That`s a really nice method, thank you for the helpful video! Hey Yumble! Great video. I do find myself with a little problem though. I use 2 lane ramps instead of 1 lane ramps and for some reason when I get to the part where I do the flyovers (8:08), the roads going over basically come together at the same spot. Any idea how I fix that? Do I have to build the guideline roads a little further apart maybe?
If people want to turn right, they're out of luck here, correct? Would we need slip lanes for that, or am I missing something? Oh, you addressed this at 14:29. Thank you.
Hi YUMBLtv, your work is an inspiration for me, but your 12m height reference is too much for me XD. I don't think in real life exist a 24m height interchange :P Anyway, i replicated this interchange with 5m height and looks gorgeous. Thank you mate :)
You’re welcome! Idk what road you’re using, but trucks cant fit under at 5m for me. I now use 10m. Keep in mind the measurement is from surface to surface, not from lower surface to bottom over the overpass like irl…
10m is still too high yumbl In the UK max height of a vehicle is 4.9m most are below 4m leaving a generous gap of 1.1m and allowing for 2m road thickness 8m would be ample and would reduce the angles on the ramps significantly.
This is a best estimate taken from local overpasses and given that I am myself 1.85 meters and the steel and concrete structures are not as tall as I am though I'm guessing these bridges will have various thicknesses depending on span, carrying capacity and construction methods
Try this, make the straight roads 0 and +12, but make the normal level +6, then have the crossover at -12 and +24. From normal level each of those is 18 cross over and 6 straight roads. Disappearing some under would be cleaner. But the one at 0 is technically trenched.
