The idea of the zipper merge is that you use both laes up until the point of merging. Then take turns merging into one lane. You make use of both lanes instead of one long lane. Some people just don’t get it though. I think there are five or so states that promote it. Mn dot takes credit for it but I remember this was discussed on talk radio long before Minnesota actually adopted it. If you think about it it makes sense. The real issue is people that like to come to a stop before merging. The faster you go the less congestion.
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A tractor-trailer is 80 feet in length, 5 vehicles would need to yield to let the truck merge, a good reason to merge when possible and not wait until the last 10 feet of pavement.
It is known that commercial trucks don’t follow cars closely so some drivers will leave the through lane, speed along for 500 feet in the lane that ends and cut in front of trucks. Watch in the mirror, a number of aggressive drivers can be seen leaving the trough lane and passing on the right until a tractor-trailer blocks their path.
When forced to drive 20 miles with lane restrictions due to road construction, rushing to the front of the line doesn’t save much time.
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I know some editors pick up the “formatting” and when it is pasted in another editor it may not treat it nicely as indicated above…
I type up all my postings in Microsoft Word, it’s a lot easier for me to see the text and the spell check catches a lot of my goofs… As for me, I highlight all my text (Control “A”), then I copy it (Control “C”), ALT, Tab, back to CarTalk, highlight text, if I want to quote it, or simply hit Reply, and I paste it (Control “V”)…
Easy Peasy, and my hands do not get Greasy…
Yes. Have you left the theoretical world and entered the real world, where for whatever reason, drivers in both lanes need to come to a complete stop before merging in? The attitude that this is my lane and you can’t merge in may be part of this. I’m not saying it’s right, but that’s how it is around here.
Maybe if the cars all left enough space for one car to move in ahead, and the attitude that this is my lane and you can’t merge was completely gone it might work. In practice they manage to bring both lanes to a near complete stop to negotiate the merging.
The graphic in that shows cars in both lanes that are following too closely. This will ensure that both lanes move at a very slow pace, maybe 10 MPH, with cars ahead frequently stopping completely, until the merge is complete.
If somebody drives in the lane that is ending at the same pace as the open lane, it prevents cars from going to the end and cutting in. Once there are no more cars doing this, then the lane speeds up to over 40 MPH. If people want to do the zipper merge, then they are free line up behind the pace car in the ending lane and begin the zipper merge when that car reaches the merging point. So whether you want to promote the zipper merge or not, having a pace car in the ending lane is a win win.
The only draw back to one line of cars is that it increases the length of the traffic back up, but not the time required to drive though it. I like the traffic back up to be longer since it alerts me of the traffic jam sooner so I can choose to take an exit to go around it.
Well better tell that to the other drivers then. 98% of the cars are lined up in the open lane and 2% are driving to the end, making the entire open lane come to a stop as they fight over the merging in at the end, and bringing the entire line down to a stop and go 15 MPH peak. If someone blocks the ending lane, it frees up everything ahead and we’re moving 40 MPH again. I’ve seen it multiple times and I don’t care what some experts think.
If somebody blocks the ending lane by acting as a pace car, the fighting over merging it at the end stops and the whole line is moving 40 MPH. In theory yes if everyone left enough space in front for a car in the other lane to merge in it would work. Publishing a pamphlet showing cars tailgating up to the merge point doesn’t help this. A lot of things work in theory. I don’t see this (the zipper merge) happening in anything short of a military convoy with everyone taking orders from a superior officer about how to drive.
People are so polite, they merge early, and then get pissed at the lane rushers. I merge early, but we are so polite. Was at an intersection the other day. Me going forward (Never Straight) northbound with a stop sign. Guy with a stop sign going southbound with left turn signal on. Westbound car, no stop sign stops to let eastbound middle of the intersection no stop turn left. That was a minute to let them figure it out.
Once again it is just math. Nothing to do with being polite. The more enlightened folks like yourself demonstrate it, the more it will catch on to those 98% in your area.
So I was in the ending lane driving the speed of the open lane. The people cutting in at the end eventually cleared out and the traffic started gradually moving faster and faster. As we a half a mile or so from the place where it goes down to one lane the traffic had speed up to about 40 MPH. There were maybe 10 cars behind me in the ending lane. As traffic sped up there was more space between cars in the open lane and more places to merge in.
Once we got to within 1/4 or so mile from the lane ending I was getting ready to merge in to the open lane rolling at 40 MPH. Then I look back and the traffic behind me has nearly stopped some distance back. The 10 or so cars behind me had decided to merge in. When they do so they somehow manage to make the open lane nearly stop. One car moves in and slows the cars behind it. Then the cars behind that one do the same. Then traffic in the open lane stops completely. The cars in the ending lane see that as an opportunety to force their way in by moving the front of their car part way in to the open lane to block traffic until they merge in.
That’s how the zipper merge works around here. Not even 10 cars that are going 40 MPH are able to do it without bringing both lanes to halt. Part of this may be that the cars in the ending lane are view as rude line cutters.
IF-AND-ONLY-IF everyone follows that rule. Here in MA and NH - it’s who can get to the line first. This is one reason why I have a Dashcam app on my phone and have it on every time I travel the interstates around here.
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Or, as done in Florida, pickup trucks and SUVs simply leave the pavement and drive on the grass, passing everybody, then squeeze back into line on the pavement.
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My coworker referred to that as “driving on the green part of the road” … lol …
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YES I belive the SUV would have been able to pass thru the area faster. Its called a ZIPPER merge, and most states have adopted it as a LEGAL and preferred merge method. Zippers shorten the number of miles that are backed up behind a merge.
Aside from the fact that those who block lanes are violating the law, they often block access to exits and interchanges by doing so.
Blocking lanes can also prevent first responders from gaining access to the incident as well as other incidents.
And the zipper merge doesn’t? Assuming the flow of traffic is the same with both methods (which I don’t believe), it makes the line of traffic half as long, so half as many exits are blocked. Is that what you’re saying?
So you’re saying it’s easier for a line of over 100 cars to move over to let a 1st responder through, than to have one car that is discouraging cars from cutting in line to move over and let the first responder through?
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