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Choadmaster
Oct 7, 2004

I don't care how snug they fit, you're nuts!

mastershakeman posted:

Figured I'd post my favorite intersection, from the town I grew up near:

What's the speed limit there? It looks like a little residential area; there are plenty of intersections in residential areas around here that have no stop signs in any direction. Traffic is slow and infrequent enough that people manage to work it out on their own. A couple three-way intersections my mom's neighborhood for example:



Granted, putting up ONE sign makes no sense and could potentially cause a lot of confusion.

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mastershakeman
Oct 28, 2008

by vyelkin
Yeah, it's just 30/35 (depending which way you're going). It's just odd having one stop sign in a totally wrong place, having 0 would make more sense.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

Choadmaster posted:

What's the speed limit there? It looks like a little residential area; there are plenty of intersections in residential areas around here that have no stop signs in any direction. Traffic is slow and infrequent enough that people manage to work it out on their own. A couple three-way intersections my mom's neighborhood for example:



Granted, putting up ONE sign makes no sense and could potentially cause a lot of confusion.

When I was new, I was designing a new intersection between two roads with about 4 houses each. I decided not to put in a stop sign, because who'd be stupid enough not to look around the corner? Heck, I grew up on a T-shaped street with no signs.
My boss made me put in the sign. Soon, I learned that people are indeed stupid enough not to look around the corner. I guess what I'm saying is, maybe some newbie engineer designed your street, mastershakeman.

Nibble
Dec 28, 2003

if we don't, remember me
Some more questions from me, since I like to think in numbers:

You've talked about cost:benefit ratio for projects a few times. Measuring cost is pretty obvious, but how do you come up with a numerical representation of benefit? Does it take into account multiple factors such as reduced congestion, improved safety, and so on?

Speaking of safety, do you try to describe the dangerousness of a particular intersection or stretch of road quantitatively? Accidents per year, casualties per year, things like that? If so, what kind of numbers describe an "average" intersection/interchange vs. a "dangerous" one? Is there anywhere I can look up stats for particular roads and intersections if I'm curious?

Related to those two, how do you prioritize new projects? Do you focus entirely on cost:benefit, or are there other factors? Do projects get bumped up in priority if they see a very high accident rate? Do the mayor's/governor's pet projects end up getting done above other objectively more important work?


Also, I took this snippet from AI and I was curious what you think.

quote:

The speed limits are consistently set artificially low, and everyone breaks them knowing they are loosely enforced. Then, when the police need to make a little bit of extra money, they have a huge pool of "criminals" to pick from. Think about it this way, how many people do you know that have never broken the speed limit? Do you really think that 35 mph is a reasonable speed for a dry five lane road at 3am? Conditions change, and most people drive a reasonable speed considering the conditions. Studies have shown that speed limits have little effect on how fast the average driver travels, but they do cause a greater disparity of speed – which is actually what’s dangerous. It’s not so bad to drive 80 mph on the freeway when everyone else is driving 80 mph, but it’s quite another if four cars are traveling at 35 mph. This isn’t the only decision that’s made in the interest of revenue generation and against your safety – in many places where red light cameras are installed, the yellow light time is decreased. Why? Because that causes more people to run the red light. Some run it out of indecision, they can’t figure out what the correct action should be, but the vast majority is stuck in a zone where they can neither stop safely nor clear the intersection before the light is red. Longer yellows are safer for the motorist, but they don’t generate nearly as much revenue. Guess which one usually wins? I’ll get off my soapbox now, but I really want you to understand that the vast majority of tickets are not about safety, and they are not about right and wrong, they are simply a means for police departments to generate revenue.

This poster is suggesting that speed limits and yellow times are often set by local police to allow them to give out more tickets, which seems to be something most drivers would or already do believe. Is there any truth to it? From what you've posted there's supposedly math done by traffic engineers to decide these things in order to make them more safe, but can local law enforcement override that or just not have engineers involved in the process?

thehustler
Apr 17, 2004

I am very curious about this little crescendo
People hate speed limits and make up conspiracy theories about "revenue generation" because they are loving babies who hate the thought of being told what to do by people who may just know better than them.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

Nibble posted:

Some more questions from me, since I like to think in numbers:

You've talked about cost:benefit ratio for projects a few times. Measuring cost is pretty obvious, but how do you come up with a numerical representation of benefit? Does it take into account multiple factors such as reduced congestion, improved safety, and so on?

It's all that, and also a reduction in maintenance costs and the eventual salvage costs. B/C ratios are tricky, so we have a whole book to help us out, known as the Red Book. It can be yours for a mere $150.

quote:

Speaking of safety, do you try to describe the dangerousness of a particular intersection or stretch of road quantitatively? Accidents per year, casualties per year, things like that? If so, what kind of numbers describe an "average" intersection/interchange vs. a "dangerous" one? Is there anywhere I can look up stats for particular roads and intersections if I'm curious?

For stretches of road, we measure accidents or fatalities per million vehicle miles or hundred million vehicle miles. For intersections, we measure per million vehicles entering. What counts as dangerous depends on what type of intersection or road it is. You can expect higher accident rates on five-lane roads in the downtown area than on freeways, because of all the left-turning traffic. The actual numbers and ranking, in Connecticut, at least, are secret and can't be had through subpoena or FOIA. The raw accident data, though, you can get from your local police department.

quote:

Related to those two, how do you prioritize new projects? Do you focus entirely on cost:benefit, or are there other factors? Do projects get bumped up in priority if they see a very high accident rate? Do the mayor's/governor's pet projects end up getting done above other objectively more important work?

Accident rate means very little. Major traffic generators (commercial plazas and apartments) and politically motivated projects are the most likely to get funded. Money we have left over can be used to fix high hazard locations, though it's generally rare unless a state senator lives nearby.

quote:

Also, I took this snippet from AI and I was curious what you think.


This poster is suggesting that speed limits and yellow times are often set by local police to allow them to give out more tickets, which seems to be something most drivers would or already do believe. Is there any truth to it? From what you've posted there's supposedly math done by traffic engineers to decide these things in order to make them more safe, but can local law enforcement override that or just not have engineers involved in the process?

Speed limits are set by influential citizens, not police. It's the "think of the children!" soccer moms and the elderly who call up the mayor and say how gol'darn fast these speed demons are driving nowadays. If they really wanted a revenue source, there are lower hanging fruit available. As to yellow times, the only one who has a say in that is the traffic engineer. It's strictly a matter of safety.

grillster
Dec 25, 2004

:chaostrump:
Lately I've been noticing how cheap the road development is in my area. Some of the heavily-traveled, two-lane roads have been widened in parts with asphalt on what seems like no reinforcement at all. Around the corner from me, there's a 25 MPH S-curve which, along with the cheap asphalt, throws you toward the edge of the road from both approaches.

I would expect this in a part of town that couldn't afford the roads, but this is a pretty well established upper-middle-class suburb. :smugissar:

Is it common for districts to pick the lowest bidder, even those with bad reputations?

Is it normal for traffic lights to have longer signals while it's wet out or raining?

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

grillster posted:

Lately I've been noticing how cheap the road development is in my area. Some of the heavily-traveled, two-lane roads have been widened in parts with asphalt on what seems like no reinforcement at all. Around the corner from me, there's a 25 MPH S-curve which, along with the cheap asphalt, throws you toward the edge of the road from both approaches.

I would expect this in a part of town that couldn't afford the roads, but this is a pretty well established upper-middle-class suburb. :smugissar:

Is it common for districts to pick the lowest bidder, even those with bad reputations?

Yes, that's the prevailing practice. If a contractor screws up badly enough to merit being banned, he'll generally swap around management and change the company's name slightly. Next thing you know, he's back on the job.

Hey, it's technically a different company, right?

quote:

Is it normal for traffic lights to have longer signals while it's wet out or raining?

Nope, I've never heard of that. Signal controllers are very very dumb, and while they can store a variety of timing plans, the only inputs a controller gets are vehicle detectors, sync pulses from the master controller, preemption calls, and electricity. There are in-pavement moisture and temperature sensors available, but it would cost an awful lot to put them at every signal.

It's assumed that people drive slower when it rains, anyway. Even if we say they're going the same speed, that max decel rate we design for (11.4 fps^2) equates to a friction coefficient of about .35, which, according to the 1984 Green Book, is what you'd find with bad tires on wet pavement. So, in a sense, it's already taken into account.

grillster
Dec 25, 2004

:chaostrump:

Cichlidae posted:

Nope, I've never heard of that. Signal controllers are very very dumb, and while they can store a variety of timing plans, the only inputs a controller gets are vehicle detectors, sync pulses from the master controller, preemption calls, and electricity. There are in-pavement moisture and temperature sensors available, but it would cost an awful lot to put them at every signal.

It's assumed that people drive slower when it rains, anyway. Even if we say they're going the same speed, that max decel rate we design for (11.4 fps^2) equates to a friction coefficient of about .35, which, according to the 1984 Green Book, is what you'd find with bad tires on wet pavement. So, in a sense, it's already taken into account.

Oh, they definitely do drive a lot slower when it rains.

What about the affect of water gathering on a sensor? Would it cause it to trip and max out the green time for that approach?

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

grillster posted:

Oh, they definitely do drive a lot slower when it rains.

What about the affect of water gathering on a sensor? Would it cause it to trip and max out the green time for that approach?

An inductive loop detector measures the change in the loop's inductance as a vehicle passes over it. If a car is moving slower than 0.1 mph, the loop probably won't detect it, because the change in inductance won't be very big. I'm not an electrical engineer, but I assume water won't have as big an effect as metal, anyway.

Loops self-calibrating these days, too. If you slowly increase the inductance of the loop, it'll decide the baseline's changed and require that much more to trip. A slow accumulation of water won't change much of anything.

potato of destiny
Aug 21, 2005

Yeah, welcome to the club, pal.
Do loop sensors "count" the cars? By which I mean, if the loop sensor is long enough to sense more than one car in the queue, does it actually do so, or detect a second car pulling up in an adjacent lane? Or is it just, "ayup, theres something there, better start the countdown timer on the other movement".

And on an unrelated note, I was looking at those HAWK signals a few pages back, and the more I think about it, the worse the idea seems to be to me. It's basically a completely unfamiliar type of traffic signal, with the disadvantage that it looks sort of like a normal light. What's the argument for using those over, say, a normal red-yellow-green traffic light that just stays green all the time unless the ped signal is actuated? Or for that matter, if it's a lower volume street, something like this:


Those are starting to pop up all over the place in Colorado, and they seem to work really well. The flashers in the sign are super bright LEDs with a kind of irregular flash pattern (sort of flash--flash--flashflashflashflashflash), and are often combined with similar in-pavement flashing LEDs. It not only draws the drivers eyes to the big sign saying "STOP FOR PEDESTRIANS DUMBASS", but also looks different enough from a traffic light to avoid confusion. I've also seen a version that incorporated a magnetic loop detector to set it off for bikes approaching the crossing, which I thought was pretty cool.

I've also been noticing that the local authorities don't seem to be wasting any time now that the new MTUCD is out; I've started seeing those shared use lane markings showing up all over the place. There aren't really enough bikes on the road to see how well it works, but I guess we'll find out as the weather starts getting better.

Jasper Tin Neck
Nov 14, 2008


"Scientifically proven, rich and creamy."

Nibble posted:

You've talked about cost:benefit ratio for projects a few times. Measuring cost is pretty obvious, but how do you come up with a numerical representation of benefit? Does it take into account multiple factors such as reduced congestion, improved safety, and so on?
The lists I've deal with at uni go pretty much like this:
  • Time savings for drivers
  • Vehicle operating costs (damage, wear, fuel consumption etc.)
  • Maintenance costs
  • Pollution
  • Noise
  • Severance (essentially how much more or less difficult it gets for some people to get across)
  • Accidents
And of course you have the unquantifiable factors such as fauna, flora, cultural landscapes and so on.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

potato of destiny posted:

Do loop sensors "count" the cars? By which I mean, if the loop sensor is long enough to sense more than one car in the queue, does it actually do so, or detect a second car pulling up in an adjacent lane? Or is it just, "ayup, theres something there, better start the countdown timer on the other movement".

Loops generally can only "see" one lane; they're 6 feet wide, and most lanes are 12. They can be used to count cars, though, which is how variable initial (mentioned back when I described signal controllers) works. The loop counts the number of cars that go past, then increases the min green time accordingly.

As to whether a single loop can tell if there are multiple cars on it, the answer is no. It can just tell if the inductance increases or decreases. You could have one car or a hundred metal blocks and the result would be about the same.

quote:

And on an unrelated note, I was looking at those HAWK signals a few pages back, and the more I think about it, the worse the idea seems to be to me. It's basically a completely unfamiliar type of traffic signal, with the disadvantage that it looks sort of like a normal light. What's the argument for using those over, say, a normal red-yellow-green traffic light that just stays green all the time unless the ped signal is actuated? Or for that matter, if it's a lower volume street, something like this:


Those are starting to pop up all over the place in Colorado, and they seem to work really well. The flashers in the sign are super bright LEDs with a kind of irregular flash pattern (sort of flash--flash--flashflashflashflashflash), and are often combined with similar in-pavement flashing LEDs. It not only draws the drivers eyes to the big sign saying "STOP FOR PEDESTRIANS DUMBASS", but also looks different enough from a traffic light to avoid confusion. I've also seen a version that incorporated a magnetic loop detector to set it off for bikes approaching the crossing, which I thought was pretty cool.

The hybrid ped signal was chosen for inclusion because a study showed it more effective than other treatments. I'm not entirely convinced, though. Generally, when a new type of traffic control is introduced, people pay a lot of attention to it because of novelty. Whether that interest fades over time is very relevant, and there aren't enough long-term studies of hybrid signals, in my opinion, to show that they'll still be as good after 5 or 10 years when they're used frequently.

quote:

I've also been noticing that the local authorities don't seem to be wasting any time now that the new MTUCD is out; I've started seeing those shared use lane markings showing up all over the place. There aren't really enough bikes on the road to see how well it works, but I guess we'll find out as the weather starts getting better.

Has your state approved the MUTCD yet, in full or in part? It might be hard to find out, so I'm not expecting an answer, just wondering :)

Cichlidae fucked around with this message at 20:26 on Feb 12, 2010

GWBBQ
Jan 2, 2005


you or someone else posted a link earlier in the thread explaining traffic jams simply as a standing wave in the flow pattern. One of the big spots for this is at entrance ramps, where nobody wants to yield to anyone else and everyone has to jam on their brakes to avoid accidents. Everyone also slows down if there's a cop parked on the side of the road, even if he's parallel to traffic and not running radar. I noticed the other day that when there was a state trooper parked a few hundred feet back from the entrance right after exit 9 in Stamford, where the merge is usually terrible, that the slowdown happened a little bit back and by the time they got back up to speed, there was enough space to merge and traffic flowed nicely for a few miles. I've been wondering if anyone has looked at strategically placing patrol cars before big chokepoints like this to smooth out traffic during rush hour, or if you have any thoughts on the idea.

Cichlidae posted:

Yes, that's the prevailing practice. If a contractor screws up badly enough to merit being banned, he'll generally swap around management and change the company's name slightly. Next thing you know, he's back on the job.

Hey, it's technically a different company, right?
Fairfield pulled one of these fuckups with our Black Rock Metro Station project and handed $19,000,000 to a guy who was convicted of multiple felonies in the '80s Savings and Loan scandal. Oops, he disappeared with the money.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

GWBBQ posted:

you or someone else posted a link earlier in the thread explaining traffic jams simply as a standing wave in the flow pattern. One of the big spots for this is at entrance ramps, where nobody wants to yield to anyone else and everyone has to jam on their brakes to avoid accidents. Everyone also slows down if there's a cop parked on the side of the road, even if he's parallel to traffic and not running radar. I noticed the other day that when there was a state trooper parked a few hundred feet back from the entrance right after exit 9 in Stamford, where the merge is usually terrible, that the slowdown happened a little bit back and by the time they got back up to speed, there was enough space to merge and traffic flowed nicely for a few miles. I've been wondering if anyone has looked at strategically placing patrol cars before big chokepoints like this to smooth out traffic during rush hour, or if you have any thoughts on the idea.

Fairfield pulled one of these fuckups with our Black Rock Metro Station project and handed $19,000,000 to a guy who was convicted of multiple felonies in the '80s Savings and Loan scandal. Oops, he disappeared with the money.

Real cops run about $75/hour. Cop cars with nobody in them are much cheaper, but commuters rapidly figure out what's up and vandalism begins. Plywood trooper cutouts soon gather bullet holes and spray paint. The best strategy is to just take a couple and move them around. Keep drivers on their toes, so they don't know where the trooper's going to be.

As to the shifty contractor, you'd be amazed how often that happens. Sometimes it seems like we're just throwing money away.

Jasper Tin Neck
Nov 14, 2008


"Scientifically proven, rich and creamy."

Cichlidae posted:

As to the shifty contractor, you'd be amazed how often that happens. Sometimes it seems like we're just throwing money away.
This keeps on puzzling me because I don't really understand how that works. Here in Scandinavia, if you want to have anything bigger than a driveway paved, you can count the companies you should call with your fingers even if you don't suffer from polydactylism. Is paving equipment significantly cheaper over there, are the project documentation requirements much looser or is your legal department just underpaid?

Cichlidae
Aug 12, 2005

ME LOVE
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Dr. Infant, MD

Nesnej posted:

This keeps on puzzling me because I don't really understand how that works. Here in Scandinavia, if you want to have anything bigger than a driveway paved, you can count the companies you should call with your fingers even if you don't suffer from polydactylism. Is paving equipment significantly cheaper over there, are the project documentation requirements much looser or is your legal department just underpaid?

Connecticut alone has at least 50 contractors available to do most general construction works. Contractors are generally local business, and there are very few national construction groups. Reason is, mobilization is a big part of construction costs. If you have to get someone to ship in a half dozen cranes, some bulldozers, and a paving train in from two states away, that gets expensive. Some guy who builds houses most of the time two towns over can rent the same equipment and work for much cheaper. Also, because codes and requirements vary so much between states, there's a definite advantage to local expertise.

Edit: As to how the same contractors get hired over and over again, it's really tough to do quality control. If one guy has paved a few roads for you, and he gets the low bid to reconstruct a bridge, are you going to say no? If you do, then you're opening yourself up to lawsuits. We also have strict disadvantaged business requirements; a certain percentage of every job must be done by minority-owned businesses. That opens the market up to contractors who otherwise might not have a chance.

Cichlidae fucked around with this message at 01:14 on Feb 13, 2010

Zero One
Dec 30, 2004

HAIL TO THE VICTORS!
I thought you might be interested in this:

http://www.nytimes.com/2010/02/12/nyregion/12broadway.html

quote:

New York’s ambitious experiment that closed parts of Broadway to vehicles last spring will become permanent, city officials said on Thursday, even though it fell short of achieving its chief objective: improving traffic flow.

Mayor Michael R. Bloomberg said that a reduction in injuries to pedestrians and motorists, along with a warm response from merchants and tourists, had persuaded him to retain the eight-month-old pedestrian plazas in Times Square and Herald Square, a marquee initiative for his administration that re-engineered the Midtown street grid.

But traffic speeds slowed on many crosstown streets, as well as on Eighth and Ninth Avenues, according to data from more than 5,700 test runs conducted by the Department of Transportation.

There were some improvements, but they mostly missed the city’s targets. Traffic along Seventh Avenue, for example, moved 4 percent faster, but the city had hoped for a gain of up to 17 percent.

Mr. Bloomberg, however, declared the project a success, emphasizing the improvements to pedestrian safety and foot traffic, along with the aesthetic enhancement to an area once associated with exhaust and gridlock.

“It’s fair to say that this is one of those things that has succeeded,” the mayor said. “Not in every way we thought, but in some ways we hadn’t thought about. Not as much in certain areas, but more than we expected in others.”

The change, which banned vehicles on Broadway from 47th to 42nd Streets and from 35th to 33rd Streets, was pitched last February as an innovative way to fight congestion. It quickly became a fascination for tourists and New Yorkers alike, drawn to the curious sight of a pedestrian mall, complete with picnic tables and folding chairs, under the neon lights.

potato of destiny
Aug 21, 2005

Yeah, welcome to the club, pal.

Cichlidae posted:

Has your state approved the MUTCD yet, in full or in part? It might be hard to find out, so I'm not expecting an answer, just wondering :)

I don't think they've adopted the 2009 one yet, as far as I can tell (Colorado, if you were wondering). They did adopt the 2003 version, and there's a law on the books requiring adherence to the federal standard (plus a state-specific supplement, all of seven pages long, mostly just clarifying a few provisions of law), so I imagine they'll be adopting it pretty soon.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

Zero One posted:

I thought you might be interested in this:

http://www.nytimes.com/2010/02/12/nyregion/12broadway.html

I'm not sure why he expected congestion to decrease. Traffic engineering can be counter-intuitive sometimes, though. Pedestrian malls like this are very common in Europe, and I'm happy to see them here. Driving through midtown is next to impossible anyway, and between the wide sidewalks and subway, cars aren't a necessity in NYC. I wonder if the idea could gain traction in a city primarily geared toward commuters.

potato of destiny posted:

I don't think they've adopted the 2009 one yet, as far as I can tell (Colorado, if you were wondering). They did adopt the 2003 version, and there's a law on the books requiring adherence to the federal standard (plus a state-specific supplement, all of seven pages long, mostly just clarifying a few provisions of law), so I imagine they'll be adopting it pretty soon.

Connecticut can't afford to implement the changes required in the 2009 edition. I hope this doesn't initiate a schism between our state and federal standards. Some of my older coworkers point out that Connecticut hasn't ever paid much attention to federal standards, aside from their disastrous choice to adopt the metric system a decade ago.

Elbonio
Dec 20, 2006

"EEETAAALAAAAA
AAAAAAAAAAAAAA
AAAAAAAAAAAAAA
AAAAAAAAAAAAAA
AAAAAAAAAAAAAA
AAAAAAAAAAAAA!"
I looked through the thread as much as I could and couldn't see anything on this, but it's a big thread so if you've answered it already feel free to tell me to shut up :v:


I want to talk about roundabouts. You guys in the states don't seem too keen on them but I think they're an absolutely wonderful thing. They seem to work so well!

So why don't you really get them in the states like you do here in the UK? You seem to prefer crossroads (do you call them intersections?).




edit: nevermind I found it on page 36. I'll leave my post here though because roundabouts are, in my opinion, one of the great inventions of the world!

Elbonio fucked around with this message at 04:51 on Feb 14, 2010

Bougie Black Women
Sep 4, 2009
How do countries deal with swapping cars over from the left side to the right, like if Canadians drove on the left side.

Bougie Black Women fucked around with this message at 05:20 on Feb 14, 2010

Cichlidae
Aug 12, 2005

ME LOVE
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Dr. Infant, MD
Edit: ^^^^^^ Also on that linked page, scroll down a bit.

Richard Nixon posted:

How do countries deal with swapping cars over from the left side to the right, as in traffic crossing the border?

This happens in only a few places worldwide. It's either done with bridges, complicated interchanges, signals, or just signs. There's a good section of Wikipedia article on it: http://en.wikipedia.org/wiki/Right-hand_drive#Changing_sides_at_borders

(How's that for a speedy reply, huh?)

Cichlidae fucked around with this message at 05:29 on Feb 14, 2010

Bougie Black Women
Sep 4, 2009
Didn't expect that, thanks.

On the topic of roundabouts, my smallish(American) city just got one- they're surprisingly fun.

Echo 3
Jun 2, 2006

I have a bad feeling about this...
Also check out the article on Sweden's switch from left- to right-hand driving. Accomplished overnight, and accident rates actually went way down for a while afterwards, presumably because everyone was paying closer attention to their driving.

mastershakeman
Oct 28, 2008

by vyelkin
On the topic of roundabouts, My dad just told me that Wisconsin passed a law that requires that planners consider a roundabout instead of a traffic light anywhere they're going to install a traffic light. I don't know how much this'll increase roundabouts, but it's a pretty good idea.

Mad Wack
Mar 27, 2008

"The faster you use your cooldowns, the faster you can use them again"

Elbonio posted:

I want to talk about roundabouts. You guys in the states don't seem too keen on them but I think they're an absolutely wonderful thing. They seem to work so well!

I live right next to this in NJ and it's a right pain in the rear end to use. However where I used to live in Kansas had about 7 or 8 roundabouts and they can be quite good. The real problem is drivers who don't expect them and do crazy things in them. Unfortunately the state I did my driver's test in never covers roundabouts and I suspect many other US states don't either.

IOwnCalculus
Apr 2, 2003





mastershakeman posted:

On the topic of roundabouts, My dad just told me that Wisconsin passed a law that requires that planners consider a roundabout instead of a traffic light anywhere they're going to install a traffic light. I don't know how much this'll increase roundabouts, but it's a pretty good idea.

I like this too. I don't know if it's actually on the books but around here it seems to be happening more often. I mentioned the newest freeway ramps for AZ Loop 202 earlier in the thread, but I'll bring them up again - they are low enough traffic that without roundabouts, they probably would have been four way stops. With lights, people would have to wait to get through at least some of the time.

With the roundabouts, I don't think I've ever seen a car wait more than a moment to get through in any direction, which is great because nothing sucks worse than waiting at a red light where nobody is moving any other direction.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

mastershakeman posted:

On the topic of roundabouts, My dad just told me that Wisconsin passed a law that requires that planners consider a roundabout instead of a traffic light anywhere they're going to install a traffic light. I don't know how much this'll increase roundabouts, but it's a pretty good idea.

Yep, New Hampshire already has this law. Now we need some explicit criteria to compare roundabout performance with signals, because our current simulation software sucks at roundabouts.

Vanan posted:

I live right next to this in NJ and it's a right pain in the rear end to use. However where I used to live in Kansas had about 7 or 8 roundabouts and they can be quite good. The real problem is drivers who don't expect them and do crazy things in them. Unfortunately the state I did my driver's test in never covers roundabouts and I suspect many other US states don't either.

I should point out that that's not a roundabout. It's too big, the throat angles are all wrong, and traffic inside the circle has to yield to incoming traffic on one leg. That's a decades-old traffic circle, and we don't build them like that anymore for a reason: they suck. Big time. Real modern roundabouts are much more effective.

IOwnCalculus posted:


I like this too. I don't know if it's actually on the books but around here it seems to be happening more often. I mentioned the newest freeway ramps for AZ Loop 202 earlier in the thread, but I'll bring them up again - they are low enough traffic that without roundabouts, they probably would have been four way stops. With lights, people would have to wait to get through at least some of the time.

With the roundabouts, I don't think I've ever seen a car wait more than a moment to get through in any direction, which is great because nothing sucks worse than waiting at a red light where nobody is moving any other direction.

Yep, remember, roundabouts work better than all-way stops in all situations, and I'd certainly prefer one over a signal in low-volume situations. Even with a semi-actuated signal, the roundabout has lower delay and, therefore, less lost time and fewer emissions! They also provide an excellent mental transition from freeway driving to city driving that a signal can't match.

Dominus Vobiscum
Sep 2, 2004

Our motives are multiple, our desires complex.
Fallen Rib

Vanan posted:

I live right next to this in NJ and it's a right pain in the rear end to use. However where I used to live in Kansas had about 7 or 8 roundabouts and they can be quite good. The real problem is drivers who don't expect them and do crazy things in them. Unfortunately the state I did my driver's test in never covers roundabouts and I suspect many other US states don't either.

God, I hate the Somerville Circle. I've only driven through it a few times, but each one was a frustrating experience.

There's also this fun one on the border of Washington, DC, and Silver Spring, Maryland. I almost ran a red light because I wasn't expecting that signal in the middle of the roundabout.

Citizen Z
Jul 13, 2009

~Hanzo Steel~


Vanan posted:

I live right next to this in NJ and it's a right pain in the rear end to use. However where I used to live in Kansas had about 7 or 8 roundabouts and they can be quite good. The real problem is drivers who don't expect them and do crazy things in them. Unfortunately the state I did my driver's test in never covers roundabouts and I suspect many other US states don't either.


Kansas puts roundabouts in some weird places. When I moved there, I was on one of the state highways(K33? K66? Something.) that they had just added a roundabout to, but hadn't put proper warning signage up. I was drastically exceeding the speed limit('cause that's what you do on flat, empty state highways. :colbert:) of 55 when I suddenly came upon the new roundabout.

I managed to not flip the car, at least.

Citizen Z fucked around with this message at 00:29 on Feb 15, 2010

Professor Bling
Nov 12, 2008

by LITERALLY AN ADMIN
This has been in my hometown since the early 1900s, and operates exactly like a roundabout.

And yes, it's hilarious to see out-of-towners stop at an entrance and wait while everyone drives around them staring.

Groda
Mar 17, 2005

Hair Elf
I moved to Sweden, and the first time I drove car there my Swedish passenger said (in Swedish), "okay, we're coming up to a rondell (roundabout)."

I reply, "what the gently caress is a rondell?"

Suddenly it came into view, and I was about a hair's breadth away from putting the brake pedal through the floorboard.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

Groda posted:

I moved to Sweden, and the first time I drove car there my Swedish passenger said (in Swedish), "okay, we're coming up to a rondell (roundabout)."

I reply, "what the gently caress is a rondell?"

Suddenly it came into view, and I was about a hair's breadth away from putting the brake pedal through the floorboard.

Citizen Z posted:

Kansas puts roundabouts in some weird places. When I moved there, I was on one of the state highways(K33? K66? Something.) that they had just added a roundabout to, but hadn't put proper warning signage up. I was drastically exceeding the speed limit('cause that's what you do on flat, empty state highways. :colbert:) of 55 when I suddenly came upon the new roundabout.

I managed to not flip the car, at least.

A good roundabout will slow you down to about 15 mph. When we changed the roundabout in Killingworth from an old 50mph traffic circle to a modern roundabout, it was amazing how many people didn't seem to notice. We spent 5 minutes looking at it from the curb, and as we were talking about the truck apron looking a bit much like a sidewalk, some old lady hit it doing 40+ and slammed on the brakes, screeching to a halt. Good thing there wasn't a pedestrian there.

More interestingly, I have a cool story about that roundabout. So settle down and listen to the tale of THE CRIME-FIGHTING ROUNDABOUT!

Killingworth is a very nice town with a view of Long Island Sound, filled with rich folks in big houses with substandard alarm systems. A cat burglar had been hitting them for months. He'd break in, steal some stuff, and drive off. Killingworth doesn't have a town police force, so it mostly went unpunished. Eventually, the state troopers managed to catch the burglar in the act. He hopped in the car and led them on a high-speed chase... toward the roundabout in construction up the road.

Now, as I said, the old roundabout was designed for 50 mph traffic. To slow people down, the center island was enlarged. As it was under construction, this meant a big mound of dirt in the middle and some forklifts and bulldozers.

The burglar, unfortunately, wasn't aware of this. He ran up to the roundabout at speed and smashed right into a dirt mound, launching him car into the air! It just barely cleared the construction equipment below, and then smashed into the pavement on the other side. The burglar clambered out and ran into the woods to hide, where he was quickly fished out thanks to the K-9 unit. The car was ruined. The construction workers had some clean-up to do the next day.

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD
Well, it's my birthday this weekend, so I was hoping for a cool present. Luckily, Stimulus Part 2 came out today! Connecticut applied for $630M; $330M for the DOT, $300M for the various towns. This is pretty important money, as you know, because we need it to fix bridges and keep our roads in decent shape. Heck, $630M is barely anything. It'll take more than that to do anything really important, like building the Busway, New Haven-Springfield High-Speed Rail, or finishing Route 11.

So, what do the feds give me for my birthday present?

Zero dollars. No dollars. Not even a penny. Absolutely nothing.

This is a HUGE slap in the face to Connecticut, especially after we got royally shafted earlier this month, getting only $40M of the $8B rail funding offered nationwide. We needed at least a couple hundred million to jump start the high-speed rail line. That was mostly Massachusetts' fault, though; they forgot to apply for the New Haven-Springfield corridor, so we got shafted as well. Heck, Vermont got more rail money than Connecticut, and we have one of the most heavily traveled rail corridors in the country. The Northeast Corridor can't run forever on 150-year-old infrastructure, and $40M isn't enough to replace even a single bridge (NEC over Route 1 in Branford was estimated at $70M).

So, why didn't we get any Stim 2 money? We spent our previous stimulus money on worthwhile projects, and generated thousands of jobs. Our contractors are starving for money, and have been doing jobs for half their estimated cost just to stay in business. If anything, now is the time to spend money! But no, we get nothing.

This has dire consequences for me, too. No money means no projects. No projects means no work for he Project Design Unit, and that includes me. What's worse: getting laid off and working for 1/2 my value, or sitting at my desk for months with nothing to do?

Any of you got a traffic engineering position open? :)

M_Gargantua
Oct 16, 2006

STOMP'N ON INTO THE POWERLINES

Exciting Lemon

Cichlidae posted:

Any of you got a traffic engineering position open? :)

Design a Quad Branch-Merge junction?

Mandalay
Mar 16, 2007

WoW Forums Refugee
do you have an amazon wish list? ;)

I'm in Boston for the weekend, first time I've been in a New England state. Rented a car yesterday and gently caress, these roads are substandard. Weaving galore, insufficient capacity even in the suburbs, and driving on the shoulder?? augh

Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

M_Gargantua posted:

Design a Quad Branch-Merge junction?

At first, I thought that was an innuendo. Then I looked it up. Daaaaaaaamn.

Edit: Downloaded and installed OpenTTD, I'm totally going to love this thing.

Mandalay posted:

I'm in Boston for the weekend, first time I've been in a New England state. Rented a car yesterday and gently caress, these roads are substandard. Weaving galore, insufficient capacity even in the suburbs, and driving on the shoulder?? augh

That's what happens when your cities were designed for horses! Driving on the shoulders seems to cause more harm than it helps, because of the reduction in shoulder integrity, loss of a breakdown lane at peak times, and inability for emergency vehicles to bypass traffic. But hey, it's not like 128's getting any wider...

Cichlidae fucked around with this message at 02:16 on Feb 20, 2010

M_Gargantua
Oct 16, 2006

STOMP'N ON INTO THE POWERLINES

Exciting Lemon

Cichlidae posted:

At first, I thought that was an innuendo. Then I looked it up. Daaaaaaaamn.

So would it actually work for cars?

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Cichlidae
Aug 12, 2005

ME LOVE
MAKE RED LIGHT


Dr. Infant, MD

M_Gargantua posted:

So would it actually work for cars?

Roads have lanes, which makes interchanges significantly easier. The road equivalent would be like a dual-divided freeway with service roads and collector/distributor roads crossing another similar road. Like so...

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