Anatomy of a Traffic Jam
I’ve just spent far far too long doing these two illustrations. The first shows a traffic jam that’s a problem, caused by people not using up all the road. The second shows what happens if the two self appointed guardians of the road move up a little, don’t block people, and if other road users don’t all try and keep to the left.
Basically, during busy periods, it’s much much better if people use all of the road. Yet in Britain it’s a common scene to see a mile of empty right-hand-lane prior to roadworks. Consequently the traffic jam is far longer than it needs to be and, in many cases, the jam will go far enough back that it blocks a junction - causing a lot of people extra delays and frustration.
So let’s all try and help others on not by obsessively queueing politely in traffic jams, but by using as much of the road as possible.
Footnotes
Since the page went up I’ve been made aware of the following two links which are very interesting and have animations of some traffic problems:
Wave motions and how to prevent them
How increased spacing helps improve merging
Thanks to brangdon @ cix for those.
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Parrot
Well said mate.
Jim
Nicely put. Also, it’s often the case that they advertise a lane closure but haven’t yet put out the cones. If you stay in the outside lane longer you will discover this and can merrily give the queuing traffic the finger as you speed on by.
teedyay
Quite.
The highway code explicitly says you should queue in both lanes and merge at the last opportunity.
Hamtouchers.
Danny Bentham
Ay up Dave. I did my Bachelors Dissertation on Traffic Management for the Future with the idea being to assess the feasibility of using wireless LAN and Kalman filtering/stereo vision/collision avoidance methods for cars to autonomously guide themselves by communicating with vehicles in a radius of X. It turned out to be one big lit review in the end and I never had any money/time to build a small scale vehicle. Whilst reading around, I found a chap who did some modelling work using Cellular Automata to simulate traffic flows. Might be worth Googling that on your lunch break one day and see what you can find.
Matt Hopley
Hi dave. Nice images. interesting read thanks for that. ive just come across your site. Brings back memories of the dissertation i did on the physics of traffic jams… heres the link if you want to add it to your site or just to have a read http://www.cactusconnects.co.uk/physics_of_traffic_jams.htm
nick
traffic in example 1 will actually get the traffic through the lane closure zone faster.
example 2, causes unnecessary traffic backups due to the fact that drivers must take turns entering the lane closure which adds extra time.
nathan
Well done bro.