This morning while driving on the freeway at rush hour, I noticed something that you've surely noticed before: rush hour is a one-way phenomenon. In the morning, the inbound lanes are jammed and the outbound lanes have only a few cars, and in the evening the sitution is reversed.
The amount of traffic on the outbound lanes in the morning (or the inbound lanes in the evening) could easily be fit into half the number of lanes (this freeway is four lanes in each direction), leaving more lanes to ease congestion. The only problem is the concrete Jersey barrier down the middle.
If the barrier were put on wheels or on a track, then the "center" of the freeway could be dynamically adjusted for traffic conditions.
During the morning rush hour, allocate five lanes for traffic going into the city and thee for outbound traffic. For the evening rush hour, reverse the allocation.
Big game at the arena tonight? Give the freeway six inbound lanes and two outbound at 5pm, and the other way around at 9pm!
Nuclear missle headed for the city? Allocate ALL the lanes for outbound traffic!
A centrally located computer system would monitor traffic conditions and adjust lane allocation to eliminate traffic congestion BEFORE a traffic jam developed!-- mwburden, Jan 03 2002 Snopes urban legend website re interstate. http://www.snopes2....os/law/airstrip.htm"Some references to the one-mile-in-five assertion claim it's part of the Federal-Aid Highway Act of 1956. This piece of legislation committed the federal government to build what became the 42,800-mile Eisenhower Interstate Highway System, which makes it the logical item to cite concerning regulations about how the interstate highway system was to be laid out. The act did not, however, contain any "one-in-five" requirement, nor did it even suggest the use of stretches of the interstate system as emergency landing strips. The one-out-of-five rule was not part of any later legislation either. " [StarChaser, Jan 04 2002, last modified Oct 04 2004] "Coning" reversible lanes in Hawaii http://starbulletin...24/news/story4.htmlThe low-tech implementation [wiml, Jan 06 2002, last modified Oct 04 2004] QuickChange(tm) Movable Barrier System http://www.barriers...nc.com/highway.htmlThe high-tech implementation [wiml, Jan 06 2002, last modified Oct 04 2004] Moveable Barriers http://www.barriers...?key=1&nav_family=1wiml's link seems to have gone stale; new location [JKew, Jun 30 2002, last modified Oct 04 2004] Road that changes direction for rush hour. http://en.wikipedia...(Hamilton,_Ontario) [knowtion, Mar 10 2009] BAKED. They're called express lanes. They put a lane between the opposite lanes, and have a gate that alternately lets the most heavily-used side have an extra lane or two or more.-- seal, Jan 03 2002 [blissmiss] The aspect that's missing from your example is that the Jersey barrier (which keeps 70mph traffic going North from occupying the same space/time coordinates as 70mph traffic going South).
[seal] That gets you 75% of the way to my idea, but there is still only one or two lanes that can be dynamically allocated. With my idea, in a civil emergency the whole freeway could become one way!-- mwburden, Jan 03 2002 Thanks to Eisenhower's Interstate Highway Act of 1956, most highways WILL be comandeered by the military in the event of a civil emergency. Didn't you ever wonder why most major interstates have long, straight stretches of road every so often for no particular reason? It's to land aircraft.-- koz, Jan 03 2002 Here in SD, the interstates consist solely of long, straight stretches. Try driving from Sioux Falls to Rapid City - for a good 200 miles it is perfectly straight and flat.-- quarterbaker, Jan 03 2002 In the case of the inbound nuke . . . you'd have to drive like hell because, I think it's only about 23 (longest case) minutes total from launch to . . . doomsday-- bristolz, Jan 03 2002 What's the difference between a tank and an american car?
The tank has better steering and does more miles to the gallon.
(Comment on striaght US roads resulting in the cars no being designed for corners.)-- CasaLoco, Jan 03 2002 CasaLoco: Methinks you haven't a clue.-- bristolz, Jan 03 2002 Koz: Urban legend, and incorrect. The roads are lined with streetlights and not usually wide enough to be used as runways. See link.-- StarChaser, Jan 04 2002 Ah, snopes.com. I wish *EVERYONE* had a bookmark to that site. Would make for a lot less drivel in my email box!-- mwburden, Jan 04 2002 Baked, as blissmiss and seal correctly pointed out. Between their annotations, your idea is covered. If one lane can be re-directed, they all can. The fact that it's not really properly implemented is a separate issue.-- snarfyguy, Jan 04 2002 [snarfyguy] As I pointed out to [blissmiss], the system in her town doesn't scale well to freeways, for which the Jersey barrier is an important safety device.
I don't see how you could convert any arbitrary number of lanes from one side to the other using the system that [seal] described (at least without putting barriers between EVERY lane, which would mean that one slow or disabled car would stop a whole lane dead in it's tracks!)
[bristolz] OK, that part wasn't really meant to be taken seriously...-- mwburden, Jan 04 2002 I believe lanes of our choosing should be cleared for any halfbakers at any time for any reason.-- thumbwax, Jan 05 2002 And that should also be applied in supermarkets, banks, etc. :)-- mwburden, Jan 05 2002 Damn right !!!!!-- Mayfly, Jan 05 2002 I've seen photos of a stretch of highway with a movable Jersey barrier. (It's actually a special barrier that's similar to a Jersey barrier.) There's an automated truck that drives down the reversable lane, scooping up barrier segments on one side and placing them neatly on the other side, twice a day. I think it's along a bridge somewhere. Presumably you could move the barrier multiple lanes by running the machine multiple times, although I think the application I saw was the middle lane of a three-lane road.
[Edit: Found it --- see link. Also found places that do the same thing but with traffic cones instead of concrete barriers --- see other link.]-- wiml, Jan 06 2002 OK, the "high tech" version is close enough to call it baked (the "low tech" version still lacks the safety of concrete barriers between opposing lanes). I would have preferred to be able to reallocate multiple lanes at once, but that's splitting hairs. My hat's off to you, [wiml]-- mwburden, Jan 06 2002 I'm from Sydney (NSW, Australia) and there's a 14 lane freeway heading to the Harbour Bridge and Tunnel across the harbour to the city. Usually (at non-peak time) there's four north bound lanes, then another three north bound. seperated by a concrete barrier from those. There are seven southbound lanes, three of which are also separated and always used as toll lanes for the tunnel (which only has a southbound toll). In the mornings when these three southbound lanes plus another one are tied up with toll paying tunnel traffic and yet another lane is a Diamond bus lane, there would only be two free lanes. So the RTA (roads authority) changed the separate three (usually northbound lanes) to southbound. They have reversible diamond exits. They've been doing this for about 10 years on the freeway since the tunnel was built.
And on the bridge, the lanes are changible too (been doing that for about 30 years). So your idea is nothing new.-- lexifer, Jun 30 2002 [lexifer], what you describe sounds like a reversible-lane system, which as you point out isn't new. A movable barrier gives you more flexibility: you can choose exactly how many lanes to have going in each direction, instead of having to reverse an entire set of lanes at once.-- wiml, Jun 30 2002 Rather than moving the barrier, could you not instead have a barrier recessed into the road between each lane? Then to switch a lane from one directionto the other you drop the barrier into the road on one side and raise the barrier from the road on the other.
This doesn't deal with the problem of signage and road markings not adapting, though.
[edited: I've since read wiml's link to the Hawaiian coning scheme and note that they do very carefully change and add signage as they adjust the lanes.]
It wouldn't work on UK motorways, either, which are normally two separate carriageways separated by a wide strip which is often used to plant signage gantries, lighting, and bridge supports in.-- JKew, Jun 30 2002 [JKew] - this does already exist on some UK motorways - the M32 into Birmingham for example.-- PeterSilly, Jul 25 2002 I'm not sure about the moveable barrier idea.
BUT, in Hamilton Ontario, there is a road that comes close to what you propose. It is one way (northbound) during rush hour morning, and southbound during rushhour evening. It is 2 way traffic otherwise.
it is called "sherman access" and is on wikipedia.-- knowtion, Mar 10 2009 We've at least one city street's middle lane north for half the day and south the other (bi-directional green/red lights hung directly over the lane)... it's scary though, no solid-white-line to the left for comfort.-- FlyingToaster, Mar 10 2009 random, halfbakery