Basketweave Interchanges

[Haljackey]

Section 17: Basketweave Interchanges


A basketweave interchange is commonly found on highways using a collector/express system or long collector/distributor lanes. In a basketweave, one highway is able to interchange with itself, allowing traffic traveling in the same direction to switch between carriageways through the use of flyover/under ramps created between two carriageways without causing weaving. These interchanges usually involve left exits and entry for the outer carriageway (right in left-hand drive) but can be configured to meet on the right.

These interchange designs are very useful for interchanging a multi-RHW or two RHWs running parallel to one-another for a short distance.

17.1: Basic Basketweave Interchange

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[Haljackey]

Section 17.1: Basic Basketweave Interchange (Created by Haljackey)

I've been contemplating for a long time as to how to create a Basketweave Interchange (without weaving) that's simple enough to make a easy-to-follow guide. I believe I have found that design.

For simplicity's sake, I am using a dual RHW-4 setup (Multi-RHW-4) all with one tile gaps. This should help minimize confusion as to what is going where.



To begin, drag your RHW-4s like so.
-You don't need to have a 1-tile gap between your inner/express RHWs, but you will need at least a 1 tile gap between the inner/express and the outer/collector lanes for this design.


Create a pair of RHW-4 type "A" ramps on the inner RHW-4s using the puzzle piece drag method.


Then, extend your MIS ramps by one tile and drag toward your outer RHW-4s. This will create RHW-4 type "A" left ramps using the puzzle piece drag method.


Just below these new ramps on the outer RHW-4s, create a pair of RHW-4 type "B" ramps (again using the puzzle piece drag method) like so:


Just above the left exit ramps you made, plop a pair of ground to elevated RHW-4 transitions. Drag the MIS that you created to go on the diagonal where these pieces end. Plop another pair of ground to elevated RHW-4 transitions on the other side.
-It may help to extend your diagonal MIS a little farther to minimize the chance of overrides. You can delete some of your inner RHW-4s to achieve this.


Plop El-RHW-4 over diagonal MIS pieces over the ramps below to complete the overpasses and ensure a working connection.
-The MIS on the inner sides of the overpasses may revert to RHW-2 at this point. Don't fret, that's ok if it happens to you!


Demolish the MIS/RHW-2 pieces that are in the way of your inner RHW-4s and re-drag them. Then create a pair of RHW-4 type "B" ramps to connect your ramps to your inner RHW-4s.


Congratulations! You've created a basketweave interchange! Here's what it looks like zoomed out:




Anyways, I hope you found this guide useful. Basketweaves are limited in their use since they don't actually interchange with any other routes but they serve their purpose well. These are must-have junctions for any player who wants to recreate a collector-express system in SC4.

Enjoy!
-Ryan (Haljackey)

[wschmrdr]

Ryan, first time poster, but I had a thought on this one to make it a little more similar to the basketweave interchange that exists in Toronto ( https://maps.google.com/maps?q=basketweave+interchange&hl=en&ll=43.718574,-79.498787&spn=0.009848,0.022724&client=ubuntu&channel=fs&oe=utf-8&t=k&z=16 ):

What if you were to use 10S with D2/E2 exits for the "express" route, and then 8S with the D2 exit on the "local" route? Perhaps raise the RHW-4 lanes to elevated (with a gap of maybe 1 or 2 tiles between this ramp and each main road), run the other ramp diagonally underneath, and then bring down to ground to re-join with the other road?

I think one of the biggest limiting factors in creating a good looking interchange is the lack of variety in left exits (or right exits if you drive on the left; being from the Americas I'm used to driving on the right), and this is why I picked 8S because there is a D2 interchange that effectively splits the road.

I'm sorry that I don't have any screen recording software, not to mention my computer is running Ubuntu so the output from WINE isn't all that good. I suppose I could just use print screen; I'll consider it over the weekend.

[Haljackey]

Oh yes I am aware of that junction... that's the iconic basketweave

I have yet to find a 'simple' way to make it so a guide can be formulated. Your idea seems like a good way to execute such a design though, but is too complex for a guide however.

I made something like it back in the RHW 4.0 days. Have a look: http://www.majhost.com/gallery/Haljackey/GTR/22.jpg

As for the lack of left exits, I actually don't mind too much myself. I would much rather have exits on the right and then have the ramp 'fly over' or under the collector lanes or maybe use a braided interchange.

[wschmrdr]

I can understand that. I'm in New York State, where we have plenty of instances of "left exits", most of which are for T interchanges (example being along I-481 with the southern part of I-81 and also the junction with I-690), but also when you need your mainline to curve to the right, like with I-90 east to I-87 south in Albany NY, and when you have two parallel interstates, although not in a true weave, see I-81/I-690.

I'll leave the left exit discussion elsewhere, as we probably want to keep basketweaves here. I really like the design on your 4.0 weave, and is actually not all that dissimilar from the concept I had of a diagonal RHW under a flyover RHW4. Hopefully I find some other good spots on this board to discuss interchanges and highways, as I really do like them, and would love to try to recreate some real ones with SC4 and the mods.

[shinkaede]

I've played SC4 for quite a while but haven't shared any of my screenshots since they are nowhere near as good as everyone else's creations here -_-.  However keeping on topic, here's a shot of a basketweave I made recently.  I made it more for the challenge and aesthetics over functionality...though it does have some usage but my sims still love their heavy rail transit.