Started By
Message

re: A reminder that zipper merging is how your supposed to handle merging

Posted on 3/24/23 at 10:40 am to
Posted by bhtigerfan
Baton Rouge
Member since Sep 2008
29742 posts
Posted on 3/24/23 at 10:40 am to
quote:

I remember from transportation class that there are models that prove that traffic moves more efficiently if the conflict point is kept at the point closest to the forced merge. I’m surprised that there are people who can’t grasp this and instead start wishing coitus on others.
There are models that show that the oceans will rise 20 feet in the next century.

So, these “models” show that traffic flows better if people wait until the last couple hundred feet to merge instead of merging a half mile or greater before the closure? I find that hard to fricking believe.

Listen, if a two lane highway is going from two lanes down to one, a slowdown is going to happen regardless because some vehicles will slow below the speed limit. But if everyone merges well before the lane closure, there should be minimal slowing. Throw in a couple of cars waiting until the end to merge, and you have people in the open lane having to slow to let them in. It just happens, people aren’t great drivers.

Real world scenario here. Sign on Interstate highway: “Right Lane Closed 2 Miles Ahead. Merge Left Now.” Traffic is moving normally, between 65-75 mph. Cars start merging into left lane, traffic probably slows to 50-65 mph in left lane and continues past the lane closure at that speed.

Same scenario with zipperheads: Traffic in left lane is moving 50-65 mph with adequate/safe spacing between vehicles, but zipperhead stays in the right lane doing 75 mph until he sees the lane closure 500 feet ahead and has to slow down to match the speed of the left lane then cuts someone off so he doesn’t hit the cones ahead and causes that person to hit their brakes, causing everyone behind them to hit their brakes and causes a chain reaction slowdown to 0-30 mph.

Great job zipperhead.
Posted by ChEgrad
Member since Nov 2012
3281 posts
Posted on 3/24/23 at 3:27 pm to
quote:

Listen, if a two lane highway is going from two lanes down to one, a slowdown is going to happen regardless because some vehicles will slow below the speed limit. But if everyone merges well before the lane closure, there should be minimal slowing. Throw in a couple of cars waiting until the end to merge, and you have people in the open lane having to slow to let them in. It just happens, people aren’t great drivers.


At any given speed, there is a safe following distance. If two lanes are filled with cars and all are following the prescribed safe distance, then no matter where the merge takes place the drivers will have to slow down to maintain that safe distance when the lanes are merged. Merging early or late will not affect this.

Your argument that early merging avoids slowdowns only works for sparse traffic with cars spaced apart greater than the minimum required safe distance. Once traffic density is high enough, a slow down is inevitable and zipper merging is more efficient and leads to order and reduced conflict as everyone should know where and when to expect the merge to occur.

This post was edited on 3/24/23 at 3:29 pm
first pageprev pagePage 1 of 1Next pagelast page
refresh

Back to top
logoFollow TigerDroppings for LSU Football News
Follow us on Twitter, Facebook and Instagram to get the latest updates on LSU Football and Recruiting.

FacebookTwitterInstagram