Flip Flop Flying

Designing an interchange

with 6 comments

For quite a while, there’s been this thing in the back of my brain. I like looking at complicated road interchanges. The most obvious examples of which (mostly because there are photos on Wikipedia) are the Gravelly Hill Interchange in Brimingham, England and the Tom Moreland Interchange near Atlanta, Georgia. Here’s photos of those interchanges, taken from Wikipedia:

The thing I have in my head is trying to imagine such an interchange with four roads where one could drive and change direction to each of the cardinal and ordinal directions of the other roads; that is, if you are on a road travelling north, you could change directing and go northeast, east, southeast, south, southwest, west, and northwest.

Why is this interesting? I dunno, it’s just something I’ve been thinking about. But it’s a fine example of why I feel the need to do infographics and organise information. What goes on inside my brain is a big fucking mess. It’s a rubbish dump. And this specific thought, about creating an image of these interchanges demonstrates that brain junk quite well.

Last night, I was messing about with the Paper app on my iPad, drawing each of the off-ramps that would be needed to change to every direction. This is what that looks like:

When I finished drawing that, I was kinda happy, but knew that it’d make more sense if I tidied it up in Photoshop. So that’s what I did this morning. But in the process of drawing it neatly (making sure each road was straight, the same width, had a different shade to denote the height off the ground, and had a border that would aid seeing where the roads overlap or meet), I noticed that I’d been thinking about it in a way too complicated way. The solution for the cardinal and ordinal junction was ridiculously simple: a big roundabout:

Normally, when I do an infographic, it’s the topic that interests me, and I want that information to be clear so I can understand it better. But doing this interchange, it’s shown me that taking something out of my brain is cathartic; it untangles the cables behind the back of the TV. And understanding things—sometimes things that don’t actually matter—is very pleasant for my brain.

Written by Craig

August 16th, 2013 at 2:11 pm

6 Responses to 'Designing an interchange'

Subscribe to comments with RSS or TrackBack to 'Designing an interchange'.

  1. ‘Pleasant’ is the best reason to explore, rearrange and try to make sense.


    16 Aug 13 at 14:33

  2. Man, I would love to see that rendered into a 3-D format. Or better yet, implemented in the real world.

    Rob H.

    16 Aug 13 at 15:07

  3. It still needs some work; especially with regard to traffic flow where cars enter the circle while others want to leave at the next ‘spoke.’


    16 Aug 13 at 15:09

  4. This stuff interests me too for unknown reasons. I was really turned on by this project in my hometown: http://www.youtube.com/watch?v=HD-0QnUlLOQ

    I remember when they started talking about the Tom Moreland style interchanges, one of the flaws it fixed was braking traffic exiting at the same place as accelerating traffic trying to enter the highway. The Tom Moreland style interchanges move those issues away from each other.

    In your photoshop example, I would suggest having the entering traffic join on the left side of the circle, or exiting traffic leave on the left side of the circle. The idea is that you want to move those away from each other.


    16 Aug 13 at 20:55

  5. That’s a really good point about having enter and exits different sides of the circle. Thanks!


    16 Aug 13 at 21:40

  6. I was reading this, and by the time I got to the first spaghetti-sketch, my brain was shouting “Come on man, you’re a Brit – the answer is obviously a roundabout!”…one day I will teach my brain to read to the end before doing things like that. :)


    19 Aug 13 at 02:41

Leave a Reply