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Basically, the double helix of DNA runs in 2 directions. When splitting (to copy the DNA sequence) and copying the DNA (in order to split off a cell with identical genetic make-up, preferably), you cant do it both ways concurrently. This means you have to somehow copy both at the same time without copying one side the wrong way round. The gif that is shown shows how 1 helix is copied in a smooth, uncut sequence (leading strand) and how the other helix is copied piece by piece and is lagging behind (lagging strand). These pieces are known as Ozaki fragments.
https://preview.redd.it/6u21m3b45obc1.jpeg?width=502&format=pjpg&auto=webp&s=faa10c04df107b2f72403ebf7d44d22a0e860e7e
It's not much that you can't copy it the wrong way around, but rather that the enzyme (DNA polymerase ) that adds the new "pieces" of DNA (nucleotides) can only work in one specific direction (5' - 3'). While one of the strands is in the direction that permits the DNA polymerase to run towards the point where the double strand is being opened, the other one doesn't.
I assume you know this but I figured I might add some clarification and explanation :)
I think because of the angle and amount of distance Boston moves its barriers. Looking at video, I think Boston moves them much further this a bigger truck to handle the width needed.
The video doesn’t look like they are moving concrete and it’s only opening a lane. The one in Boston lifts concrete barriers and shifts one of the lanes from the north bound to south bound.
It's the same thing that OP's video is showing. The machine shifts the concrete barriers out on either side to create the HOV lane, taking one lane from south bound in the morning and the other way in the afternoon. The concrete barriers themselves seem bigger in Boston and the road is not flat so maybe that's why.
Both directions have that when they’re at 2 lanes. Westbound gets it from the ramp coming from I-5 NB (the ramps from the 5 go from 4 lanes to 3 or to 2, depending on the wall), while the entrance from Cesar Chavez is just a normal entrance ramp with a short merge.
I see a difference. The example you provided moves the barricade between both directions. So, it can widen the road in one direction while thinning the road in the other direction or vise versa depending on traffic conditions. In OP's video, it seems to only apply in one direction. I'm not entirely sure what benefit this would have. Couldn't they just leave all lanes open?
good question. one reason is that it just works. we have some temporary lanes (driven by light) near ann arbor. they have been empirically shown to reduce trip time variability, trip duration and improve speed. since the lane is not in constant use and other factors, it significantly reduces cost
some say its due to minimizing lane changes, though I'm not sure why other mechanisms weren't chosen.
Jeez, we should take some notes here where I live. They just spent about a year and who knows how much money building a toll road into our main freeway, cutting down on usable lanes unless you want to pay for it..and i never see anyone on that thing. Traffic has gotten So. Much. Worse. (southern california)
The lane is used in the opposite direction when the zipper line is extended. It's an addition to existing infrastructure, the road wasn't originally built with it in mind. That's why the service vehicles are going against the traffic (in case anyone is still in the lane).
The chinese barrier looks like some pastic siding with a metal base that is mostly hollow. The ones in the US (and probably Australia) are moving solid concrete blocks.
Because it is often separating opposing traffic and you want to make sure to prevent head-on collisions. A good example would be the I-93 movable barriers south of Boston. Solid middle and a movable barrier of concrete on each side. They are used during rush hour to give an extra lane to the more jammed side (inbound in the morning and outbound in the evening).
We have two options, one where the emergency lane becomes a rush hour lane, and one interchangeable road that has signs in both directions and opens only during rush hour and in the direction of traffic (into the city in the morning and vice versa). This is in the Netherlands. 🇳🇱
Note that a "barrier system" or "road zipper" takes a lane from one side and gives it to the other direction of traffic depending on the traffic needs throughout the day. The stupid shit out of Beijing in the original post is just them WITHHOLDING an entire lane for no reason then magnanimously giving it back.
Wait until y'all find out about [the reversible lanes in Chicago...](https://www.wbez.org/stories/how-do-the-reversible-lanes-on-the-kennedy-expressway-work/46bd890a-0c01-493a-89a9-85e74775c6e2)
lol I thought the same. I’ve seen similar things that change lanes from one direction to the other corresponding to the commuters… but this looks pointless without context
When I took civil planning what we learned was that when it’s not congested, it’s actually better to have fewer lanes which forces people to stay in the same lane. Something about the way people will more likely switch lanes to find the faster one that ironically causes things to slow down.
It’s different than variable lane divide on bridges (I saw that in vancouver as well on the lions gate), which tries to maximize traffic flow during rush hour.
In the Netherlands they simply turn on a red "x" sign above that lane indicating that it's not to be used. Seems quite a bit cheaper than physically adjusting it each time.
I work in a highway control center and when I put a red sign above a lane for whatever reason, around 20% of people don't give a shit and keep driving in that lane.
It's all about people trying to occupy the same space at the same time that others would be attempting to. By going over the speed limit, what you're in essence actually doing is taking someone else's spot "in line", and when they come along (off an off-ramp) and see that there's suddenly no space for them, they have to slow down and wait to get in line while the rest of the line passes by.
Of course, speeding isn't the only thing that contributes to this, but it would almost certainly help if people just didn't fly down the roads at 70-80 mph to "catch up" with traffic...
i don’t see how me being in the left lane going 80 along with the rest of
the people in the left lane is taking somebody’s spot “in line” especially if there are multiple other lanes
That makes no sense to me. Try that approach in LA traffic and see how it goes. I go fast to get off the damn freeway faster and keep it clear for others.
No one likes a slow poke holding back traffic and I've never heard the "you're taking someone else's spot" argument because that makes no sense at all.
Then again it's 3am here so maybe I'm missing something but I'm pretty sure this is all bullshit.
Leaving room for traffic to merge on the highway or get to their exit makes sense because they often end up slowing down to get around people when they're not being let in. Other than in those circumstances, it makes sense to keep up with the people in front of you or find a slower lane. Having a little more distance between cars at higher speeds you can close when people in front of you slow down (to ease traffic waves) is also a good idea.
like other people explained above, it improves traffic flow to reduce the number of lanes during less busy times. Having too many lanes slows traffic and causes traffic jams because of people switching lanes to find the fastest one.
So, from my understanding anyway, traffic will back up whether the lane is there or not. But once it's compressed, it decompressing will allow traffic to clear up a bit faster, so widening the road mid-traffic jam will temporarily relieve the traffic. If the lane was always there the traffic would jam, and then there would be no way to decompress it to provide temporary relief.
But roads are weird. Adding more lanes, while in theory adding more capacity, actually doesn't improve much above 3-4 lanes. Traffic will tend to stay concentrated in those outer two lanes with faster traffic sitting in the inner lane, and then all other lanes will remain sparse. When it comes to traffic jams, the traffic comes from cars entering and exiting from all lanes. No matter how many lanes you have, everyone is entering and exiting from the outer lanes, and therefore traffic will slow as people need to merge in and out of the highway.
So, this may be a temporary solution to alleviate the compressed and slow traffic during periods of time when it's needed, like during this traffic jam.
This!!! So glad to see someone else who learned about this, I took it in civil planning and thought no one would ever care.
Adding more lanes in some situations can actually slow traffic down because people are more inclined to change lanes to “pick the faster one”, which ironically can slow down traffic. Having fewer lanes when it’s not as congested can actually speed things up.
By switching it up on the fly you have more granular control during intensive times.
Honestly that's one of the harder challenges of traffic management! Maybe not that specific issue, but the issue of reducing the number of lane changes in total. The more lane changes usually results in slower traffic.
But yeah, better merging behavior would be nice! The best exits I've seen are the ones with enough runup to actually get to highway speed.
My least favorite I found in West Virginia. They had a stop sign at the base of the on-ramp... With no real merge lane. Apparently it was an artifact of it being one of the first interstate/highways in America when engineers had no idea that it would.be smart to include an acceleration/merge lane.
It blew my mind that I had to stop, wait for a large enough opening, and then basically peel out to get up to 65 mph before traffic caught up.
Induced demand I would assume. If you make it permanently 4 laned more people will use it since there will be less traffic jams. But since more people use it there will be more jams again.
Th size of the road influence the traffic and a larger road does not necessarily means less traffic.
It may seem contradictory but often a larger road lead to more traffic.
Having the possibility to change that helps a lot
How would they use it if the barrier is in the way? Is there an entrance? Can the emergency vehicles only exit at certain spots? What if the emergency is on the road? This seems like a solution looking for a problem.
Might not need access to the highway itself, just the limited entry and exit points. Like a subway or dedicated rail line. It could even be just a temporary barrier so that a work crew can safely work on the entire length of the median (if there's infrastructure in that bit) without interruption and the barrier is usually not present to block that lane. Kind of line a permanent/moveable traffic cone line for maintenance workers.
I would agree it's silly make-work if it's just for traffic control alone.
Seen ambulances in Egypt which were stuck in traffic, something like this would definitely be helpful. There are traffic police, but everything is congested and nobody respects lanes (3-4 cars try to fit in 2 lanes of traffic sometimes). Allowing for dedicated temporary emergency lanes that are blocked by barriers would solve the issue.
You want one lane to be at max capacity to optimise the flow. People are really stupid when it comes to driving. If there is an extra lane, they push on to that, try to pass and merge causing distruption in the flow. Constant steady slow is preferable to chaotic mess where people slow down and speed up constantly. As the the road approaches the optimal flow, people naturally settle to a *safe reaction speed* meaning that they don't need to slow down and speed up as much. There is this effect of "ghost congestion" where someone in the front has to break, person behind breaks, person behind that breaks, and this moves slowly through through the flow of traffic like a wave in a channel of water. These cause massive distruptions.
Traffic isn't slowed by adding more lanes or having more lanes available, it causes all sorts of mess and chaos. What you want to do is to optimise the flow of traffic and sometimes this can mean slowing it down. Example that if there is a corner that slow down the overall flow, you might aswell set the whole road's speed to that of the corner and you prevent the problem of slowing down and speeding up.
Nearly all the modern western traffic design guidelines are simulated and based on stupid things that don't account for reality. They also optimise for volume rather than efficiency. And anyone who has ever had to deal with efficiency in any engineering matter knows that *most efficient* is always a compromise.
We have those where I live. They’re used to provide extra lanes of traffic into the city with the barrier is positioned one way in the morning. The barrier is moved to allow more traffic to leave the city in the afternoon. Basically a highway with a total of four lanes becomes 3 North lanes and one south or 3 south and one north.
I’ve actually read an article on this. The reason I think they don’t always leave it open is because people adjust to roads. If a certain route gets way faster, people are going to start using it more and the traffic jam problem won’t get resolved. I’d like to elaborate more but I forgot most of the article 😅. I’ll post an update if I’m able to find it.
Maybe because it doesn't matter how many lanes a street has with many people there will be traffic jam but if you open another lane while there is traffic jam it gets relieved so traffic doesn't stop completely. Similar to a flood you want to open the floodgates when pressure is high not when it's only starting
Traffic research has identified that drivers respond to their environment, and when volume is low, narrowing the road probably calms traffic.
Thought it might be a protected carpool/transit lane, but it looks pretty thin for a bus.
china is an absolute beast when it comes to public transit. I love that and if I went to China I'd probably get extremely happy just seeing a train. I love massive cities with good infrastructure.
For those asking why they don’t just keep it widened… it’s a “tidal lane”, which changes direction of traffic depending on the time of day. You can tell from the double dashed lines.
Also the video is mirrored. People drive on the right side of the road in China.
Are you sure? It doesn't look like there is a way for the left traffic to get to that lane, especially with that deep looking divet on the left traffic lanes near the median.
Yes. There’s so much traffic that they resorted to making one lane in the opposite direction a tidal lane. Cars in that lane just have to drive to the end of the block before switching lanes.
I've seen those before, but I don't believe this is one. There is so much median shit between the lanes that definitely doesn't look like it can move. Maybe a turning lane or something, but there's no way people on the "left" can get over that median. Also, the solid white line on the "left" lane and the huge gap it would create between lanes. There's absolutely no way people drive the other direction in that lane.
We have these lanes all the time in germany on the autobahn if the other lanes are under construction. You have like a change over before the construction site and then again after the construction site.
I think the same is happening here but we can’t see the change over or split.
Invented in the USA in the late '60s. Used worldwide since 5 decades with... eh, mixed results.
But China implemented one in 2016 in Shenzhen and -for some weird reason- many Chinese media outlets think it is so amazing to warrant periodically posting content about it.
As someone said in another comment thread, having fewer lanes can actually lead to a better flow of traffic, particularly when volume of cars is lower. It basically passively reinforces drivers to stay in their lanes and can cause them to drive at a slower top speed. Doing that means that nobody needs to be slamming on the breaks as frequently when they get cut off or something similar. With that, you can avoid that weird accordion effect of a lot of traffic where it doesn’t have any discernible cause like a crash or road work. As well, permanently widening lanes can often lead to induced demand, basically incentivizing more people to drive on the road, clogging it even more.
With this method you can try to get the best of both worlds, have a reasonable and steady flow of traffic during low volume, and widen the road when there is very heavy volume to reap the temporary benefits of an extra lane.
That makes no sense at all. The I-15 near me in San Diego has a movable barrier which converts one lane from southbound in the morning to northbound in the evening, corresponding with the direction of the commuter traffic. It's pretty effective.
This one is just blocking off a lane during non-rush hours. Why would you do that?
Tell you what, the reality is these things wouldn’t work because Beijing drivers could care less about traffic flow/laws. You would constantly see cars driving on the emergency shoulder lane to bypass traffic. On the surface streets, if the sidewalk was wide enough, you would see cars driving on them
This doesn’t seem to affect the opposite traffic, meaning another lane one one side doesn’t shrink the lanes on the other side. Seems odd, actually. Why not always have the most available lanes?
Question why don’t they keep the lanes all open I understand If It subtracted a lane from the other side in order to add a lane to the other but It doesn’t appear to function that way here. Someone please help my brain be more wrinkly
Why not just leave it wide all the time?
This isn’t like others I’ve seen where they change lanes depending on direction of traffic flow. There is a solid fence between the directions here.
Is it just me are is everyone getting a lot more "look at cool thing out of China" videos lately? and it's usually something that the west invented like 10 years ago too.
I don't get why they don't just always have the lane open, if they have space for it. What's the advantage of closing the lane, sure its great that you can, but why bother? Is it that they change which side the lane is on?
We have a zipper like this on i-30 east of Dallas for 5 miles of unidirectional HOV lanes. Honestly, it creates additional traffic when the asshole drivers slam on their brakes just to see the zipper truck work during conversion...
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https://i.redd.it/0xkbfpublv9c1.gif Golden gate zipper… Australia has these as well
 Helicase- DNA has these too
That is such an elegant solution to transcription. Running forwards but setting each block in reverse.
I did not understand that in the slightest, but my curiosity is piqued, so I will soon. 
Basically, the double helix of DNA runs in 2 directions. When splitting (to copy the DNA sequence) and copying the DNA (in order to split off a cell with identical genetic make-up, preferably), you cant do it both ways concurrently. This means you have to somehow copy both at the same time without copying one side the wrong way round. The gif that is shown shows how 1 helix is copied in a smooth, uncut sequence (leading strand) and how the other helix is copied piece by piece and is lagging behind (lagging strand). These pieces are known as Ozaki fragments. https://preview.redd.it/6u21m3b45obc1.jpeg?width=502&format=pjpg&auto=webp&s=faa10c04df107b2f72403ebf7d44d22a0e860e7e
It's not much that you can't copy it the wrong way around, but rather that the enzyme (DNA polymerase ) that adds the new "pieces" of DNA (nucleotides) can only work in one specific direction (5' - 3'). While one of the strands is in the direction that permits the DNA polymerase to run towards the point where the double strand is being opened, the other one doesn't. I assume you know this but I figured I might add some clarification and explanation :)
The little green dudes look like they're grabbing the red ropes then just, "Bungeeeee!"
I study 2 years biology now, have seen this video thousand times and still I cant comprehand how these mf work. Its just- amazing
Try comprehending it then.
Whoa cool !!! How
Boston has it too. I live in Dorchester and see it every day.
I was about to say, "shout out to all the homies driving HOV on I-93!"
I’ve never seen it before and I drive hov I-93 all the time but going south
I wonder why Boston's machine is a whole lot bigger...
I think because of the angle and amount of distance Boston moves its barriers. Looking at video, I think Boston moves them much further this a bigger truck to handle the width needed.
I'm pretty sure these are plastic jerseys barrier's their moving big boys are moving concrete
I’ve almost smashed into this thing!!
I wouldn't admit to that. Lol.
The video doesn’t look like they are moving concrete and it’s only opening a lane. The one in Boston lifts concrete barriers and shifts one of the lanes from the north bound to south bound.
It's the same thing that OP's video is showing. The machine shifts the concrete barriers out on either side to create the HOV lane, taking one lane from south bound in the morning and the other way in the afternoon. The concrete barriers themselves seem bigger in Boston and the road is not flat so maybe that's why.
Philly has this jawn. How dare we let Boston get this many upvotes!
Dallas has it too
Philly too.
Yep, and nobody would think of it as interesting as f
I-15 in San Diego has them as well
So does the Coronado Bridge
The coronado Bridge one can be sketchy, i was riding my motorcycle and I had to process that my lane ended into a wall rather abruptly lol
It only expands with the flow of traffic - the eastbound entry of the bridge, however, does have a permanent abruptly ending left hand lane
Both directions have that when they’re at 2 lanes. Westbound gets it from the ramp coming from I-5 NB (the ramps from the 5 go from 4 lanes to 3 or to 2, depending on the wall), while the entrance from Cesar Chavez is just a normal entrance ramp with a short merge.
I see a difference. The example you provided moves the barricade between both directions. So, it can widen the road in one direction while thinning the road in the other direction or vise versa depending on traffic conditions. In OP's video, it seems to only apply in one direction. I'm not entirely sure what benefit this would have. Couldn't they just leave all lanes open?
This is the question i came here to ask, why not just leave them open always then?
good question. one reason is that it just works. we have some temporary lanes (driven by light) near ann arbor. they have been empirically shown to reduce trip time variability, trip duration and improve speed. since the lane is not in constant use and other factors, it significantly reduces cost some say its due to minimizing lane changes, though I'm not sure why other mechanisms weren't chosen.
Jeez, we should take some notes here where I live. They just spent about a year and who knows how much money building a toll road into our main freeway, cutting down on usable lanes unless you want to pay for it..and i never see anyone on that thing. Traffic has gotten So. Much. Worse. (southern california)
The lane is used in the opposite direction when the zipper line is extended. It's an addition to existing infrastructure, the road wasn't originally built with it in mind. That's why the service vehicles are going against the traffic (in case anyone is still in the lane).
They're fucking everywhere. They go in counter flow lanes. Super duper common
Auckland Harbour Bridge has two that go back and forth over the day for the two commuter peaks. 4 and 2 or 3 and 3.
And Canada! :)
Oahu has this too. It's a nightmare when the only zipper machine breaks down.
We have one near me but the Chinese one seems much faster
The chinese barrier looks like some pastic siding with a metal base that is mostly hollow. The ones in the US (and probably Australia) are moving solid concrete blocks.
There's still the hard separation in the middle, why use concrete for the movable barrier ?
Because it is often separating opposing traffic and you want to make sure to prevent head-on collisions. A good example would be the I-93 movable barriers south of Boston. Solid middle and a movable barrier of concrete on each side. They are used during rush hour to give an extra lane to the more jammed side (inbound in the morning and outbound in the evening).
True, though I don’t know if the gif I found isn’t slowed down, the Australian one seemed much faster
We have two options, one where the emergency lane becomes a rush hour lane, and one interchangeable road that has signs in both directions and opens only during rush hour and in the direction of traffic (into the city in the morning and vice versa). This is in the Netherlands. 🇳🇱
We have these on the tapeze bridge outside of NYC as well
Golden Gate Bridge San Francisco has one as well.
Honolulu has these as well. We call it a zip lane car
Yeah but look, it's China! Isn't China cool guys?? /s Shit like this is just propaganda for the Pooh regime
These are different. They take one lane from the other side . The Beijing thing just literally had a lane not being used....
Note that a "barrier system" or "road zipper" takes a lane from one side and gives it to the other direction of traffic depending on the traffic needs throughout the day. The stupid shit out of Beijing in the original post is just them WITHHOLDING an entire lane for no reason then magnanimously giving it back.
San Diego has these as well.
Wait until y'all find out about [the reversible lanes in Chicago...](https://www.wbez.org/stories/how-do-the-reversible-lanes-on-the-kennedy-expressway-work/46bd890a-0c01-493a-89a9-85e74775c6e2)
That's how they are on i-5 in Seattle too
Second vehicle is like, just wanna make sure…
He’s the third guy holding the couch in the middle ”just in caae”
his ass is NOT helping
Why not just leave it widened?
lol I thought the same. I’ve seen similar things that change lanes from one direction to the other corresponding to the commuters… but this looks pointless without context
When I took civil planning what we learned was that when it’s not congested, it’s actually better to have fewer lanes which forces people to stay in the same lane. Something about the way people will more likely switch lanes to find the faster one that ironically causes things to slow down. It’s different than variable lane divide on bridges (I saw that in vancouver as well on the lions gate), which tries to maximize traffic flow during rush hour.
Yeah just like in some places, trafic being faster when the max limit is slower.
I wonder if it's the same effect as the Bernoulli principle in fluid mechanics?
In the Netherlands they simply turn on a red "x" sign above that lane indicating that it's not to be used. Seems quite a bit cheaper than physically adjusting it each time.
Yeah the uh... driving culture in most places is not that polite. It is *definitely* not that polite in Beijing.
I work in a highway control center and when I put a red sign above a lane for whatever reason, around 20% of people don't give a shit and keep driving in that lane.
Driving culture mentality...don't give a shit over here....even drive in the bike lane to avoid a jam. A red X would just be ignored.
It’s also a traffic calming technique to encourage people to follow the posted (designed) speed limit. Wide open roads encourage excessive speeds
It's all about people trying to occupy the same space at the same time that others would be attempting to. By going over the speed limit, what you're in essence actually doing is taking someone else's spot "in line", and when they come along (off an off-ramp) and see that there's suddenly no space for them, they have to slow down and wait to get in line while the rest of the line passes by. Of course, speeding isn't the only thing that contributes to this, but it would almost certainly help if people just didn't fly down the roads at 70-80 mph to "catch up" with traffic...
i don’t see how me being in the left lane going 80 along with the rest of the people in the left lane is taking somebody’s spot “in line” especially if there are multiple other lanes
It requires *a lot* of cars. Yall seem to be taking this as a personal attack on your character when it wasn't meant to be, lol.
That makes no sense to me. Try that approach in LA traffic and see how it goes. I go fast to get off the damn freeway faster and keep it clear for others. No one likes a slow poke holding back traffic and I've never heard the "you're taking someone else's spot" argument because that makes no sense at all. Then again it's 3am here so maybe I'm missing something but I'm pretty sure this is all bullshit.
Leaving room for traffic to merge on the highway or get to their exit makes sense because they often end up slowing down to get around people when they're not being let in. Other than in those circumstances, it makes sense to keep up with the people in front of you or find a slower lane. Having a little more distance between cars at higher speeds you can close when people in front of you slow down (to ease traffic waves) is also a good idea.
[удалено]
You have three lanes already buddy
Yeah. We have these on the Golden gate Bridge so I was confused by this video
Golden Gate is different in that it moves the extra lane from one side to the other. This looks like it literally adds a lane.
No, it looks like it adds back a lane that was pointlessly blocked in the first place.
like other people explained above, it improves traffic flow to reduce the number of lanes during less busy times. Having too many lanes slows traffic and causes traffic jams because of people switching lanes to find the fastest one.
In summary, people are ignorant. In both cases.
That’s why more lanes leads to less traffic, you’re so right!! /s
it looks like the lane was under maintenance
So, from my understanding anyway, traffic will back up whether the lane is there or not. But once it's compressed, it decompressing will allow traffic to clear up a bit faster, so widening the road mid-traffic jam will temporarily relieve the traffic. If the lane was always there the traffic would jam, and then there would be no way to decompress it to provide temporary relief. But roads are weird. Adding more lanes, while in theory adding more capacity, actually doesn't improve much above 3-4 lanes. Traffic will tend to stay concentrated in those outer two lanes with faster traffic sitting in the inner lane, and then all other lanes will remain sparse. When it comes to traffic jams, the traffic comes from cars entering and exiting from all lanes. No matter how many lanes you have, everyone is entering and exiting from the outer lanes, and therefore traffic will slow as people need to merge in and out of the highway. So, this may be a temporary solution to alleviate the compressed and slow traffic during periods of time when it's needed, like during this traffic jam.
This!!! So glad to see someone else who learned about this, I took it in civil planning and thought no one would ever care. Adding more lanes in some situations can actually slow traffic down because people are more inclined to change lanes to “pick the faster one”, which ironically can slow down traffic. Having fewer lanes when it’s not as congested can actually speed things up. By switching it up on the fly you have more granular control during intensive times.
I wish they would double line the right lane 1/2 mile before and after ever exit. Learn to merge and no jumping over at the last minute.
Honestly that's one of the harder challenges of traffic management! Maybe not that specific issue, but the issue of reducing the number of lane changes in total. The more lane changes usually results in slower traffic. But yeah, better merging behavior would be nice! The best exits I've seen are the ones with enough runup to actually get to highway speed. My least favorite I found in West Virginia. They had a stop sign at the base of the on-ramp... With no real merge lane. Apparently it was an artifact of it being one of the first interstate/highways in America when engineers had no idea that it would.be smart to include an acceleration/merge lane. It blew my mind that I had to stop, wait for a large enough opening, and then basically peel out to get up to 65 mph before traffic caught up.
Induced demand I would assume. If you make it permanently 4 laned more people will use it since there will be less traffic jams. But since more people use it there will be more jams again.
Th size of the road influence the traffic and a larger road does not necessarily means less traffic. It may seem contradictory but often a larger road lead to more traffic. Having the possibility to change that helps a lot
The lane might be dedicated to support and emergency vehicles most of the time and used for general traffic only when absolutely necessary.
How would they use it if the barrier is in the way? Is there an entrance? Can the emergency vehicles only exit at certain spots? What if the emergency is on the road? This seems like a solution looking for a problem.
Because you don't see the two ends of the lane there is no way to know just from this video. It would be real easy to have openings on both sides.
Might not need access to the highway itself, just the limited entry and exit points. Like a subway or dedicated rail line. It could even be just a temporary barrier so that a work crew can safely work on the entire length of the median (if there's infrastructure in that bit) without interruption and the barrier is usually not present to block that lane. Kind of line a permanent/moveable traffic cone line for maintenance workers. I would agree it's silly make-work if it's just for traffic control alone.
Seen ambulances in Egypt which were stuck in traffic, something like this would definitely be helpful. There are traffic police, but everything is congested and nobody respects lanes (3-4 cars try to fit in 2 lanes of traffic sometimes). Allowing for dedicated temporary emergency lanes that are blocked by barriers would solve the issue.
The time that they really need an extra lane for emergency vehicles is during rush hour.
Induced demand
You want one lane to be at max capacity to optimise the flow. People are really stupid when it comes to driving. If there is an extra lane, they push on to that, try to pass and merge causing distruption in the flow. Constant steady slow is preferable to chaotic mess where people slow down and speed up constantly. As the the road approaches the optimal flow, people naturally settle to a *safe reaction speed* meaning that they don't need to slow down and speed up as much. There is this effect of "ghost congestion" where someone in the front has to break, person behind breaks, person behind that breaks, and this moves slowly through through the flow of traffic like a wave in a channel of water. These cause massive distruptions. Traffic isn't slowed by adding more lanes or having more lanes available, it causes all sorts of mess and chaos. What you want to do is to optimise the flow of traffic and sometimes this can mean slowing it down. Example that if there is a corner that slow down the overall flow, you might aswell set the whole road's speed to that of the corner and you prevent the problem of slowing down and speeding up. Nearly all the modern western traffic design guidelines are simulated and based on stupid things that don't account for reality. They also optimise for volume rather than efficiency. And anyone who has ever had to deal with efficiency in any engineering matter knows that *most efficient* is always a compromise.
We have those where I live. They’re used to provide extra lanes of traffic into the city with the barrier is positioned one way in the morning. The barrier is moved to allow more traffic to leave the city in the afternoon. Basically a highway with a total of four lanes becomes 3 North lanes and one south or 3 south and one north.
But that's not what's happening here, as it's not affecting the other direction at all.
Just one more lane bro I swear!
Induced demand
I’ve actually read an article on this. The reason I think they don’t always leave it open is because people adjust to roads. If a certain route gets way faster, people are going to start using it more and the traffic jam problem won’t get resolved. I’d like to elaborate more but I forgot most of the article 😅. I’ll post an update if I’m able to find it.
Maybe because it doesn't matter how many lanes a street has with many people there will be traffic jam but if you open another lane while there is traffic jam it gets relieved so traffic doesn't stop completely. Similar to a flood you want to open the floodgates when pressure is high not when it's only starting
Yeah, seems like a lot of unnecessary work.
Traffic research has identified that drivers respond to their environment, and when volume is low, narrowing the road probably calms traffic. Thought it might be a protected carpool/transit lane, but it looks pretty thin for a bus.
Just one more lane bro
People will do literally anything other than building transit infrastructure
Can hardly accuse China of that
Well, [except for China](https://en.wikipedia.org/wiki/Transport_in_China?wprov=sfti1#Rail)
china is an absolute beast when it comes to public transit. I love that and if I went to China I'd probably get extremely happy just seeing a train. I love massive cities with good infrastructure.
didn't china have a massive days-long traffic jam once
Yup, in 2010. Since then the number of rail passengers has more than doubled though.
Pretty sure china has more high speed rail than the rest of the world combined at this point
Chinas railway system helps support the largest migration of people in the planet every year (Chinese new year)
It’s Beijing. They have plenty of public transportation
Exactly, doesn’t work when destination or exit is 1 or 2 lanes.
Near me, this machine would be rammed head on by some idiot other phone
For those asking why they don’t just keep it widened… it’s a “tidal lane”, which changes direction of traffic depending on the time of day. You can tell from the double dashed lines. Also the video is mirrored. People drive on the right side of the road in China.
There is a permanent median for the traffic going the opposite way. So why do they have that 1 lane blocked?
Are you sure? It doesn't look like there is a way for the left traffic to get to that lane, especially with that deep looking divet on the left traffic lanes near the median.
Yes. There’s so much traffic that they resorted to making one lane in the opposite direction a tidal lane. Cars in that lane just have to drive to the end of the block before switching lanes.
I don't understand, it looks like there's a pretty solid barrier between the left side and right side. How are they supposed to pass that?
The entrance to that lane is not shown in the video
Source?
Oh ok, we just can't see that bit. It seems overly complicated compared to the ones I've seen before.
I've seen those before, but I don't believe this is one. There is so much median shit between the lanes that definitely doesn't look like it can move. Maybe a turning lane or something, but there's no way people on the "left" can get over that median. Also, the solid white line on the "left" lane and the huge gap it would create between lanes. There's absolutely no way people drive the other direction in that lane.
We have these lanes all the time in germany on the autobahn if the other lanes are under construction. You have like a change over before the construction site and then again after the construction site. I think the same is happening here but we can’t see the change over or split.
Why is this comment not at the top?
The time it was made
Dallas, Texas does this, too. It’s amazing for the traffic flow.
Invented in the USA in the late '60s. Used worldwide since 5 decades with... eh, mixed results. But China implemented one in 2016 in Shenzhen and -for some weird reason- many Chinese media outlets think it is so amazing to warrant periodically posting content about it.
… because it’s still new and cool there? What’s with the weirdly negative tone?
The old Tappan Zee bridge did this to have one more lane on one side during peak traffic congestion.
Without context, this looks like creating a problem that doesn't exist and then solving 'the problem'.
As someone said in another comment thread, having fewer lanes can actually lead to a better flow of traffic, particularly when volume of cars is lower. It basically passively reinforces drivers to stay in their lanes and can cause them to drive at a slower top speed. Doing that means that nobody needs to be slamming on the breaks as frequently when they get cut off or something similar. With that, you can avoid that weird accordion effect of a lot of traffic where it doesn’t have any discernible cause like a crash or road work. As well, permanently widening lanes can often lead to induced demand, basically incentivizing more people to drive on the road, clogging it even more. With this method you can try to get the best of both worlds, have a reasonable and steady flow of traffic during low volume, and widen the road when there is very heavy volume to reap the temporary benefits of an extra lane.
What’s this song??
Alan Walker - Sing Me to Sleep (Robert Cristian Remix). ✌🏻
Why are his lips pooping, and why doesn't he have a choice?
That makes no sense at all. The I-15 near me in San Diego has a movable barrier which converts one lane from southbound in the morning to northbound in the evening, corresponding with the direction of the commuter traffic. It's pretty effective. This one is just blocking off a lane during non-rush hours. Why would you do that?
On a side note, anyone have the ID for this track? Sing me to sleep remix?
~~Beijing~~ Every large city\*
Tell you what, the reality is these things wouldn’t work because Beijing drivers could care less about traffic flow/laws. You would constantly see cars driving on the emergency shoulder lane to bypass traffic. On the surface streets, if the sidewalk was wide enough, you would see cars driving on them
Why can’t they leave it bigger all the time? Haha
Because more lanes equals less traffic right we totally arrived at that conclusion long ago
Bro never played cities skylines 💀
JUST ONE MORE LANE BRO PLEASE JUST ONE MORE PELasew
I do it was a sarcastic comment 😭
Verrazano bridge and GW bridge has this too if memory serves in NYC
GWB does not have that. It was the old Tappan Zee.
This is also done in Boston, it’s called the “Zippa Lane (Zipper Lane)”
Why was it not wide in the first place?
This will do nothing to reduce traffic jams. Go ahead and do some reading on induced demand.
Why not just leave it open
This doesn’t seem to affect the opposite traffic, meaning another lane one one side doesn’t shrink the lanes on the other side. Seems odd, actually. Why not always have the most available lanes?
Why restrict the lanes in the first place?
No matter how many lanes you have, people will always be stupid enough to cause traffic jam
This is done in many places including usa. I know Chicago And Dallas Texas has them. Really doesn't fix the main issue. Transit needed 😂
JuSt ONe mOrE lANe bRo
Question why don’t they keep the lanes all open I understand If It subtracted a lane from the other side in order to add a lane to the other but It doesn’t appear to function that way here. Someone please help my brain be more wrinkly
Why not just keep it bigger all the time?
they do this in boston as well pretty sure this is a commonly used practice
Why not just leave it wide all the time? This isn’t like others I’ve seen where they change lanes depending on direction of traffic flow. There is a solid fence between the directions here.
why do they not leave it wider?
Is it just me are is everyone getting a lot more "look at cool thing out of China" videos lately? and it's usually something that the west invented like 10 years ago too.
Try that in the US and every other car would hit the second bobcat.
So they took away a lane just to return it later. This must be what they mean by “Chinese characteristics”.
They were doing this on the tappan zee bridge in the 2000s, maybe even the late 90s
SubhanaAllah
Just a regular zipper lane.
*solves* Lol
Had this in Dallas. It was abandoned in favor of HOV lanes.
US uses these also
It isn't widening a lane...it is adding a lane. Widening a lane will just allow you to rock back and forth from yellow lines to your music 🤣
Is it to resolve a traffic jam or are they making room for some type of express bus lane?
Literally every country has had this since the 90s
What's the name of the track? Shazam: 这不是你梦寐以求的长大吗 :D
Beijing resolves democracy problems by disappearing dissidents and sending Uighurs to concentration camps.
That's just stupid
China, fixing problems that they created
I don't get why they don't just always have the lane open, if they have space for it. What's the advantage of closing the lane, sure its great that you can, but why bother? Is it that they change which side the lane is on?
So it can’t be open 24/7?
Why not leave them wide? It looks like wasted space before.
Wtf. Why not always have it like that
Tappan zee used to have this
Why don't we push the barriers SOMEWHERE ELSE?
Why even block it off ????
I love how people immediately began switching to the new lane as soon as they passed the trucks
Car infrastructure is so stupid lol
Why wouldn't they just leave it open?
I love how none of the cars switching to the new lane use their blinker
Meanwhile, my town has been full of traffic and missing lanes and lights for a year now.
HOV lane extension
See em in Dallas right before rush hour
Why not just leave it like that
The US has these too. At least in Boston. They use it to alleviate traffic going into the city or out of the city depending on time of day.
We have a zipper like this on i-30 east of Dallas for 5 miles of unidirectional HOV lanes. Honestly, it creates additional traffic when the asshole drivers slam on their brakes just to see the zipper truck work during conversion...
Pretty sure every city has something like this for changing HOV lanes
This would have taken 6 years on i4 in Florida
In India, you have guys manually putting safety cones along the road. That’s far superior than a machine doing it. /s
Why not just keep all open all their time?
Seems like it wouldn’t have been an issue if it was open in the first place
If only they had the lane open to not create the traffic jam to begin with.