Using 1 Way Roads As Big Highway Ramps?

[Twan]

Hey everyone, I just bought the game a week ago and really love it.

Is there any reason I can't use one way roads for on/off ramps from/to highways (besides cost)? I was having a nasty traffic issue where a six lane road and an offramp from the highway met, so I rearranged it and basically removed the off ramp and sawed off both directions of the highway, so now the two lane highway turns into the six lane one way road coming into the city, and right next to it, another six lane one way road turns into the highway leading out of town (I would have used a four lane road but there is no four lane one way road for some reason), and it really seems to have fixed the traffic jam nicely.

I can't really figure out how to eliminate jams with two lane roads leading into my six lane roads though, for example the areas where I connect my housing block to the six lane road. I basically have a six lane road making a ring around my city with connections to my blocks after a certain distance to make long distance travel faster.

Thanks!

[ancienthighway]

If you don't have it already, pick up Mass Transit next time it's on sale, probably around Christmas. This DLC will give you more road options.

On your six lane ring road, rather than putting a T intersection in to connect your residential zones, treat the six lane as a highway. In fact, if you aren't zoning off of the 6-lane, change it to a highway for faster speeds.

[ExavierMacbeth]

There really isn't a reason you can't. The only two issues i can really think of off the top of my head is the way theg ame handles traffic may not use all the extra lanes so you could still end up with a very long line of cars. And the second issue being that there is a speed limit difference between the road types so under really heavy traffic conditions you might get a mess from slowing the highway down.

[Twan]

Hmm, ok thanks guys, so that brings up a question on the reverse scenario; I can use a ramp to connect a road to a non-highway road?

And no, I'm trying not to zone off of the six lane road, it looks wierd and there's noise pollution.

@Exavier; yeah I think I read something about if you use a regular road instead of a ramp, the highway will only use one lane past a certain point and may get backed up.....Or something like that.

[MarkJohnson]

I like using the large highway roundabout to terminate highways. They aren't perfect, but they do a very good job.

But for on or off ramps, streets are terrible. The traffic will merge multiple lanes at once causing traffic jams.

Here's an example of using a highway as an off ramp.

https://www.youtube.com/watch?v=Cl65wHGXJYQ

[ExavierMacbeth]

Basically the traffic AI is coded to look for the shortest physical route, not the fastest route. So if all the traffic is comming from the same direction & headed to the same desitnation (most noticable with entrence/exit to city) they have a tendancy to always pick the exact same route & lane even if that lane has a traffic jam half a city long with the other lanes on the same road being empty.

The Traffic Manager Presidents Edition I believe has additional AI route controls to try and encourage cars to switch lanes periotically which alviates some of the issues but figuring out a good traffic plan is usually better. Thats why roundabouts are so popular for city entrances and other high traffic areas. A good roundabout never slows down (no traffic lights) and keeps the traffic moving constantly.

One practice I have gotten into is setting up one way roads in and out of opposite ends of my neiborhoods then rotating the exits 90 degrees for the next one. This pretty much forces traffic to constantly use different routes so the only heavy traffic spot in my city is the line of industry trucks headed to/from the highway. I don't even need to worry about mass traffic until the area hits about 80% high density :)

Though the one way roads do play merry heck with getting city service coverage sometimes. So every solution does have tradeoffs.

[OneJasonBradly]

Originally posted by ExavierMacbeth:

Basically the traffic AI is coded to look for the shortest physical route, not the fastest route.

Basically!!
The rule "is" they will travel the QUICKEST route/path Not the SHORTEST for the SHORTEST Route/path may travel at a slower speed limit making it the longer route/path.
Proof #1
http://steamcommunity.com/sharedfiles/filedetails/?id=1153174585
Proof #2
http://steamcommunity.com/sharedfiles/filedetails/?id=1193466554



@Twan. Your answer is also in the first clip clip above. Yes you certainly can connect ramp pieces to other pieces of roads. I do that quite often.
http://steamcommunity.com/sharedfiles/filedetails/?id=1142302843
have a look I use ramp and slow road pieces together to create larger spacing between vehicles so they merge together easier.

[OneJasonBradly]

Using two lane roads or more as on ramps to highway will disrupt the lane assignment and pathing for or on the highway.
With single ramp On ramp. have you noticed when traffic approaches an On ramp they will often clear the right lane (that is if there is no offramp just after the onramp) to allow traffic to enter the highway without having to yield at the ramp. Using more than one lane to enter the highway would mess this lane clearing mechanic up and might cause two lanes to try to clear.

If you have a large volume of vehicles trying to leave the highway and are bottlenecking at the ramp concider two exits. This will mean you will need to figure out the two destinations to do so. I have made double. tripple and quad exits to handle volume of traffic. Spite the advice that I should focus on reducing traffic instead, wimps.

Here I show a triple exit on the right side.
http://steamcommunity.com/sharedfiles/filedetails/?id=864930921

Here I created a double exit. One for industry and the other for everyone else.
http://steamcommunity.com/sharedfiles/filedetails/?id=1120154535

keep experimenting like you are doing! Learn the traffic, too many give up and go find traffic mods. They are fun though not needed and will harm you saves at larger populations if you them without traffic knowledge.

[Twan]

Wow, lots of advice to think about here, love this game, thanks everyone