[RunsTheBitterroot]

Anyone ever figure out how 4 lanes of traffic can be at a standstill for miles? On occassion I have been near the front of one of these and I don't see why the slowdown occurs and why so many lanes are effected. Is there a science to this?<br><br>
Larry

 

[Stitcher]

Oh yes....<br>
but it's VERY complicated...<br>
involving sun spots, the rotation of the earth, and the position of Venus in Aries.<br><br>
Or..........<br>
so I hear.

 

[maccabeth]

Yeah. It's the idiots in the front who initially slow down and the sheep behind them that get stuck. Just MOVE people!!!<br><br><br><br>
(uh, yeah. I have traffic issues. I get very very anxious.)

 

[muzicgrl]

I think it comes from the road not being able to handle the sheer number of cars. When enough people exit then the traffic ends up magically clearing up. I have recollections of this from a seminar I went to with my civil engineer friends in college about traffic management.

 

[Nettie]

Yeah, I took a class that dealt with traffic when I was in e-school, but I still wouldn't be able to intelligently explain this.

 

[Lintu]

There are that many people in Montana?<br><br>
Sure it's not cattle in the road?

 

[Stitcher]

I"m stickin' with sunspots and planetary alignment!

 

[ElDuderino]

Here in San Diego we blame tourists from Arizona.

 

[4boysmom]

One person taps on their brakes. Everyone behind them hits their brakes. And so it goes. For miles, traffic is at a stand still. Once you get past the point where the first guy tapped his brakes, it's smooth sailing. Why the first guy hit his brakes doesn't matter. Maybe he just dropped his Oreos or something. But it will snarl traffic for hours!

 

[RunsTheBitterroot]

No not in Montana, wildlife, cattle, sheep and the occasional dumping of a load of hay in the road are the only roadblocks around here. Might add the traffic lights from hell in Missoula. I was just reminising about the traffic back in my city days down south. It is one of those questions about life, like "what happend before the big bang" another mystery.<br><br>
Larry

 

[antagonist]

Live in L.A. and then talk to me about traffic.<br><br><img alt="biggrin.gif" src="http://files.kickrunners.com/smilies/biggrin.gif">

 

[QuixoticNotions]

I saw some research about the echo effects of small things when there is a high volume of traffic-- something as little as braking a little because someone merges in front of you echos back a mile through the traffic and magnifies. I don't remember all of it though.<br><br>
I was driving near the head of traffic the other day here on 400 (which added a lane recently and got MUCH better than it once was) -- and maneuvered my way to the very top, listening on the news to the near standstill miles behind me-- it was just a bunch of cars that couldn't be bothered to go a reasonable speed at the front. If you're only going to go 60, that's fine, but why are you in the left lanes?

 

[Chupacabra]

It's from the dumb-asses who always think the other lane is moving faster, jump over into a hole that they barely fit into and make the car they cut off slam there brakes on. This is repeated over and over and makes the slowness continue much longer than it should have.

 

[choovie]

I was starting to wonder if Western Montana had gotten more populous than I remembered.<br><br>
My favorite MT traffic jam was caused by a load of spilled manure spread across both lanes of traffic. Three cars backed up while trying to decide if they should try to drive through it or not. I noticed this while walking along next to the road picking wild asparagus. Suddenly, a pickup from the other direction came speeding along and everything became slow motion. I knew he was going to plow through the manure so I started to run. Unfortunately, I wasn't fast enough and ended up with manure raining down on me.

 

["Roberto"]

Too many cars merging onto the highway.<br><br>
Slow cars in the left lane.<br><br>
People filling holes like in the opening scene of Office Space.<br><br>
Sun glare, no really!<br><br>
And last to my knowledge is the accordion effect, sorta like what QN said about the problem magnifying behind you when you tap your brakes.<br><br>
The only real solution is to maintain a safe distance behind the car in front of you (yeah, like that's gonna happen), don't brake check tailgaters, remain in the middle lane unless passing, and leave the right lane open for merging on and off the highway.<br><br>
How you like me now?<br><br>
I study traffic patterns for a living.<br><br>
No, not really, just when I am stuck in them.

 

[diablita]

I agree with a lot of these, though y'all missed one:<br><br><span style="font-size:x-large;"><b>F*&%$NG RUBBER-NECKING</b></span><br><br>
OK, not that I'm bitter or anything. But if you f&%$#ers would just drive instead of slowing down to see the accident on the other side of the freeway, we could all get home. Wouldn't you rather spend more time with your family than see yet another ambulance????

 

["Roberto"]

I'm guilty of laying down on the horn when it is rubberneckers. <img alt="banana.gif" src="http://files.kickrunners.com/smilies/banana.gif"><img alt="banana.gif" src="http://files.kickrunners.com/smilies/banana.gif">

 

[OldBaldHippie]

what a visual!....hah...the shit hit the fan...

 

[refinnej10]

Here's everything I know about the science of traffic (which, frankly, isn't much)<br><br>
Any given highway has a capacity. This capacity is the number* of cars that can safely share the road at the posted speed limit.<br><br>
If the number of cars on the road exceed that capacity, the speed will go down and the system will be highly susceptable to any perturbation.<br><br>
In a circumstance in which the traffic flow is near capacity, very small perturbations of the system can set off a jam.<br><br>
An example of a perturbation could be someone tapping their brakes. If car #1 hits hir brakes and slows down 5mph, then car #2 (behind car #1) has to tap their brakes and slow down ~10mph (because of the delay in reaction time, further slowing must occur to prevent hitting), Car #3 has to slow down 15mph... etc.<br><br>
On ramps and exchanges also have a capacity which may or may not be the same as the capacity of the road. On an exchange there's a limit to the number of cars that can get though (per hour) before it starts to get congested. Once the on ramp gets congested, it starts to slow down the main road, which if it is at or near its capacity, can cause futher jams.<br><br><br>
*technically capacity is a rate, so #cars/hour, not a precise number of cars.

 

[RunsTheBitterroot]

Seen along a Montana Highway.<br><br><img alt="" src="http://i6.photobucket.com/albums/y202/RunsTheBitterroot/mtrestarea.jpg" style="border:0px solid;"><br><br>
Larry