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Cichlidae posted:Fight the power So let me ask you a question about that. The city of Long Beach CA recently lowered the speed limit on a portion of Pacific Coast Highway. Here is map of the general area: http://maps.google.com/maps?f=q&sou...92,0.04004&z=15 On PCH south of the 7th Street, the speed limit used to be 50mph and north of 7th Street it used to be 45mph all the way to the traffic circle way north. Does this seem like it is correct? No one goes 40 on this stretch of road except for old people.
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Apr 12, 2010 22:01
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Wiggly posted:So let me ask you a question about that. The city of Long Beach CA recently lowered the speed limit on a portion of Pacific Coast Highway. Here is map of the general area: That's a question I can't answer just with an aerial photo. There's a whole procedure to determine freeflow speed, and it's not something you can figure out without a decent first-hand look at the road. Or, you could go the easy route and just time cars and get the 85th percentile speed. That's what the speed limit SHOULD be. Heck, it even says so in the MUTCD. Doesn't get much clearer than that. So, if most people are still driving 50-55, the speed limit should be 55. Lowering it only creates a hazard.
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Apr 12, 2010 22:43
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Cichlidae posted:That's a question I can't answer just with an aerial photo. There's a whole procedure to determine freeflow speed, and it's not something you can figure out without a decent first-hand look at the road. Or, you could go the easy route and just time cars and get the 85th percentile speed. That's what the speed limit SHOULD be. Heck, it even says so in the MUTCD. Doesn't get much clearer than that. So, if most people are still driving 50-55, the speed limit should be 55. Lowering it only creates a hazard. California law does require that the speed limit on PCH be set at the 85th percentile, unless there are specific reasons (high rate of accidents, hidden driveways, schools) along that stretch to lower it. Wiggly should supposedly be able to get ahold of the assessment for that area to see what the speed surveys say and what the reasoning behind the speed limit is (should be public record), but I have no clue how to go about doing that. Edit: Hey Wiggly, I looked at your map and noticed that stretch of PCH is where Green Field Churrascaria is. I rarely go to Long Beach, but when I do it's usually to eat there. It's a bit pricey but it's loving delicious. 
Choadmaster fucked around with this message at 01:20 on Apr 13, 2010 |
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Apr 13, 2010 01:09
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Cichlidae posted:Boy, you don't mince words
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Apr 13, 2010 03:39
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GWBBQ posted:I make no secret of the fact that I do not like Rell and have not at any point in the past. The retiree healthcare deduction is there so that in 10 years when whatever Republican shithead we elect tries to gently caress over the unions again and ditch retiree healthcare, SEBAC can tell them that these people have been paying into the retiree healthcare system for ten years and are not going to be left out in the cold. The fact that I don't plan to work for the state long enough to be fully vested in the retirement plan screws me, but hey, that's part of the job. There's talk of not getting our raises for this year and last year until October if at all, I hope they're just rumors. I suppose it depends on your bargaining unit. I'm in P-4, and we have a pretty solid contract negotiated. I'm sure you saw the letter Rell's goon sent out a couple weeks ago; while our contract says that we're allowed to renegotiate if the projected shortfall goes beyond 350M, we only really have to consider some additional concessions. Even then, I think the union can just choose not to re-open negotiations. Given their response (in which they effectively call Rell evil), I'm hoping that'll be the case, and that we can get a decent governor elected and not another one of Rowland's lackeys. Sorry for the political mini-derail 
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Apr 13, 2010 04:18
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Cichlidae posted:I suppose it depends on your bargaining unit. I'm in P-4, and we have a pretty solid contract negotiated. I'm sure you saw the letter Rell's goon sent out a couple weeks ago; while our contract says that we're allowed to renegotiate if the projected shortfall goes beyond 350M, we only really have to consider some additional concessions. Even then, I think the union can just choose not to re-open negotiations. Given their response (in which they effectively call Rell evil), I'm hoping that'll be the case, and that we can get a decent governor elected and not another one of Rowland's lackeys. But anyway, back to traffic. I mentioned a few weeks ago that they put up some streetlights on the Parkway around the West Rocks Road bridge, which is being renovated. Are they likely to leave those or just keep them until the project is done (scheduled for next year)? I'm one of the few people who likes driving on an unlit road and I hope it stays that way. They also have what looks like a steel structure to brace the bridge, how exactly do they repair the historic bridges? I also saw some guys power washing a bridge the other day (where Black Rock Turnpike goes under the Parkway at exit 44,) and they were walking around on top this morning, I assume the washing was part of the inspection routine?
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Apr 15, 2010 00:05
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GWBBQ posted:But anyway, back to traffic. I mentioned a few weeks ago that they put up some streetlights on the Parkway around the West Rocks Road bridge, which is being renovated. Are they likely to leave those or just keep them until the project is done (scheduled for next year)? I'm one of the few people who likes driving on an unlit road and I hope it stays that way. I'm not involved in that project, but we do have a spec for temporary lighting. Since the Parkway is historic, it's unlikely that they're making a permanent change. quote:They also have what looks like a steel structure to brace the bridge, how exactly do they repair the historic bridges? I also saw some guys power washing a bridge the other day (where Black Rock Turnpike goes under the Parkway at exit 44,) and they were walking around on top this morning, I assume the washing was part of the inspection routine? Funny you should ask. One of the bridges up here over 15 (built around the same time) is falling apart so badly that we put wire mesh underneath to catch the rocks. We can't save all of the bridges; for the Route 7 / Route 15 interchange project, we'll need to rip up a few historic ones. Like the Route 111 bridge, we'll just put up new ones with stamped concrete that looks similar to the old. As for rehab, it'll probably be power washing, full depth patching, and some structural repairs where needed. We really don't have the cash for replacement.
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Apr 15, 2010 01:57
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Cichlidae posted:Or, you could go the easy route and just time cars and get the 85th percentile speed. That's what the speed limit SHOULD be. Maybe I missed this somewhere, but is the 85th percentile speed measured at a certain percentage of capacity? I live in MA and commute on the I95/128 loop every day. In the morning (6:30AM) I can do 80mph and be passed regularly. In the afternoon (4:30) I'm lucky to average 45mph because of congestion. If you want a crappy interchange to look at, check this one at Route 9 and I95. 4 lanes southbound drop to 3 at the Rte 9 exit right after picking up all the extra volume from I90. They try to mitigate it during rush hour so that south of 9 we're allowed to drive on the shoulder as if it was a lane (from 6-10AM and 4-7PM I think) but that area always backs up. http://maps.google.com/?ie=UTF8&ll=42.316067,-71.234515&spn=0.013074,0.018475&t=k&z=16
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Apr 15, 2010 03:03
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I'm curious how egregious a fuckup this local highway situation is. http://maps.google.com/maps?f=q&sou...009645&t=h&z=17 The route in question basically has you take the fork off to the right heading southbound on the Ronald Reagan turnpike, taking that loop, where you get to a section where an offshoot of the North bound turnpike meets up with it, intersects, where there's basically a 400 or so foot section where traffic ends up cross-merging. It's got a disproportionate amount of accidents in that area, and there have been some articles about it but nothing really in depth or technical.
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Apr 15, 2010 03:56
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mungtor posted:Maybe I missed this somewhere, but is the 85th percentile speed measured at a certain percentage of capacity? I live in MA and commute on the I95/128 loop every day. In the morning (6:30AM) I can do 80mph and be passed regularly. In the afternoon (4:30) I'm lucky to average 45mph because of congestion. Since the speed limit is an upperbound, it makes sense to set it when speeds are high. Germany, though, has variable speed limits, and some roads in the States have done the same. They change based on traffic conditions. As to the interchange, wow. I didn't think anyone would add a lane inside the weave like that. Also, there are at-grade crosswalks across the freeway ramps! That certainly doesn't seem prudent. Since you use 128 a lot, what do you think of MassHighway's campaign to get rid of it altogether? I likes having 128 (and, to an extent, having the exit numbers based on it). Now it's been cut back, and MassHighway's removing the 128 plaques from all the directional signs. I'll miss 128. (95 should have been its own freeway, anyway.) Catfish Noodlin posted:I'm curious how egregious a fuckup this local highway situation is. That's called a quadrant interchange, and it's common on low-volume freeway-freeway junctions where either there are toll booths or there isn't enough room at the overpass for ramps. Unfortunately, as you noted, this creates a weaving area; four of the eight movements have to cross traffic. Normally, this is offset by making the connecting road as long as feasible. In this case, it's not very long at all. There are ways to fix it (flipping the connecting road to the southwest quadrant is one expensive one), and even some well made signs or inlaid route plaques in the pavement could reduce the conflicts slightly.
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Apr 15, 2010 12:40
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Cichlidae posted:Germany, though, has variable speed limits, and some roads in the States have done the same. They change based on traffic conditions. Where are they in the States? I hope they're proving successful, as I'd love for them to be implemented around D.C. There are some areas with 4+ lanes of what seems like perfect asphalt to an Ohioan like me in each direction where the speed limit is 55 MPH. That's just absurd and I'm told it's due to traffic during rush hour, so there's a perfect candidate for variable limits. At night those roads are so empty and smooth that I don't think there should be a limit at all, but sure enough there are plenty of cops out taking advantage of the lack of radar detectors in the area.
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Apr 16, 2010 01:41
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wolrah posted:Where are they in the States? I hope they're proving successful, as I'd love for them to be implemented around D.C. I saw some variable speed limit signs on... the Jersey Turnpike, I think? The MUTCD has provisions for electronic speed limit signs, so hopefully they'll be implemented. Unfortunately, knowing state government, they'll probably start at the current permanent speed limit and just decrease in congestion or bad weather.
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Apr 16, 2010 01:53
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wolrah posted:Where are they in the States? I hope they're proving successful, as I'd love for them to be implemented around D.C. I-90 in Factoria (near Bellevue, WA) has a few! They're pretty sweet, as are the signs that say how long it's going to take to get to certain areas based on traffic specific route.
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Apr 16, 2010 02:33
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Cichlidae posted:
As a transplant to MA, I can't say that I really mind. It seems like a lot of people have some emotional investment in Rte 128 as a concept (drat gub'mint not gonna tell me 'bout my road) but for me it's never made a difference. The coolest thing about this thread is learning what should have happened. This is where the I95/I93 interchange should have let I95 start heading through downtown. http://maps.google.com/?ie=UTF8&t=h&ll=42.20859,-71.139393&spn=0.013096,0.018475&z=16 I've driven that to get on 95 South hundreds of times and never noticed the northbound ramps to nowhere, but Google maps makes it obvious once you know the story. Cichlidae posted:I saw some variable speed limit signs on... the Jersey Turnpike, I think? The MUTCD has provisions for electronic speed limit signs, so hopefully they'll be implemented. Unfortunately, knowing state government, they'll probably start at the current permanent speed limit and just decrease in congestion or bad weather. Driving the Jersey Turnpike to visit family for Thanksgiving I can say that appears to be exactly it. The variability in the limit only extends downwards, but like so many highways it seems the "accepted" upper limit is about 80mph regardless of the posted speed.
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Apr 16, 2010 03:04
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mungtor posted:As a transplant to MA, I can't say that I really mind. It seems like a lot of people have some emotional investment in Rte 128 as a concept (drat gub'mint not gonna tell me 'bout my road) but for me it's never made a difference. It's because Route 128 was there first, mostly. I've always seen I-95 as only being temporarily routed there. But then again, it is a trait of Rhode Islanders like me to refer to roads and businesses by their names from 30+ years ago. My dad still occasionally calls I-395 Route 52, for example, and my mom shops at the Almacs down the street, even though it hasn't been Almacs since the early 1990s. quote:Driving the Jersey Turnpike to visit family for Thanksgiving I can say that appears to be exactly it. The variability in the limit only extends downwards, but like so many highways it seems the "accepted" upper limit is about 80mph regardless of the posted speed. Yep. If people feel safe driving 80 (and the road's like 300 feet wide, so I don't see why not), they're going to drive 80 no matter what the speed limit says. Heck, my coworkers have some pretty high-end cars, and often end up cruising around 120 just because it seems like a good speed when you're on a 3-mile straightaway with no traffic.
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Apr 16, 2010 04:12
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I went to a press conference today for the kickoff of Work Zone Safety Week, so maybe you'll see me on the news. To celebrate this important week, it's time for a triple dose of Work Zone Safety Activity Booklet! Barri Cade and his unnamed brother explain their role in covering holes. The dynamic pair will double-team any road, any time. What do you expect when you've got wood 24/7? One thing is for sure: these two are into safe sex.  Doris Drum offers some slightly out-of-date information about street name signs. They must now be mixed upper and lower case, and red is also allowed as a background color. I've shown my street sign as an example.  Ima describes fun things we can DO, like Handicap. I love Handicap!  Tyler Tube explains that brown = fun. I would like to note that Tyler likes to hang out in wastewater treatment plants and leather tanneries. I've seen Tyler's house; he has cameras installed under the toilet seats. I dare not say what has entered those clown lips of his, but the word 'cornlog' comes to mind. Do not take advice from Tyler.  Ima demonstrates some of his (her?) favorite signs. Not much to say here.  Doris points out the subtle differences between a five-sided and four-sided sign. I, for one, know that I will "look for the books" the next time I see a ped crossing sign. It's vitally important to know whether I'm about to run over a student or an ordinary (dare I say, pedestrian?!) ped.
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Apr 17, 2010 00:44
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Cichlidae posted:It's because Route 128 was there first, mostly. I've always seen I-95 as only being temporarily routed there. But then again, it is a trait of Rhode Islanders like me to refer to roads and businesses by their names from 30+ years ago. My dad still occasionally calls I-395 Route 52, for example, and my mom shops at the Almacs down the street, even though it hasn't been Almacs since the early 1990s. 128 won't go away as the route number has been codified into MA state law after the last push. MassDOT may be trying to get rid of things referring to 128, but it will still be 128 so long as it has pavement.
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Apr 17, 2010 03:57
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I have a question about reflectors on posts along the interstate. White obviously marks the right of the road and yellow the left, but what about green? While driving along a section of I-96 in Michigan I noticed a stretch with additional green reflectors on both left and right sides of the roadway, in the median, and far off to the right of the roadway almost to the edge of the right of way. I couldn't really identify a pattern for the green reflectors, so I was wondering if you could shine some light on what these might be marking. Thanks.
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Apr 19, 2010 06:33
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ibpooks posted:I have a question about reflectors on posts along the interstate. White obviously marks the right of the road and yellow the left, but what about green? While driving along a section of I-96 in Michigan I noticed a stretch with additional green reflectors on both left and right sides of the roadway, in the median, and far off to the right of the roadway almost to the edge of the right of way. I couldn't really identify a pattern for the green reflectors, so I was wondering if you could shine some light on what these might be marking. Thanks. The MUTCD specifies that each delineator must be the same color as the line it's adjacent to. On a freeway, that means yellow on the left, white on the right. On a two-way roadway, the delineators on both sides should be white (something Connecticut hasn't quite figured out yet; I'm sure many states are the same.) There are only three colors of stripes: yellow, white, and purple, maybe red if you're counting truck escape ramps. No green. What does this tell us? Green markers aren't traffic control devices. They're for some other purpose, perhaps wetland delineation or marking culverts or dips so the lawnmowers don't hit them, in which case they'd be called object markers. I'll ask my boss today (he's from Michigan) if he can add any details. Edit: He doesn't have anything to add. Cichlidae fucked around with this message at 21:44 on Apr 19, 2010 |
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Apr 19, 2010 12:38
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Funny to see such a thread pop up on SA, I guess there are transportation professionals and enthousiasts all around the web though. I'm currently interning at an engineering firm and as an economic historian I'm writing my thesis on the growth of the Dutch freeway network. I've immersed myself a bit in the 'roads community' and there's lots of discussion about roads and transportation going on in the relevant sections of skyscrapercity here, most Dutch-speaking road enthousiasts hang out on the wegenforum. There's somewhat of a road-building renaissance going on in Holland after decades of NIMBYist sentiments blocked most capacity building projects. Concurrently, traffic jams grew from a couple of tens of kms per day on the entire network of 2000~2500 kms 25 years ago to 200~300 kms per day during rush hour. That's more than 10% of an entire countries' through-traffic network jammed twice a day. Rail and bus services are already well-developed and the demographic and spatial organisation of the country precludes new public transport initiatives of reaching even modest cost/benefit goals. So despite a non-permmissive legislative framework, which has slowed freeway construction down to 14-year long planning cycles for individual projects, it looks like the Netherlands will finally get some projects done the coming decade. So here's a sneak peek of the A1-A6-A9-A10/Schiphol - Amsterdam - Almere (SAA) widening Some interchanges will be completely rebuilt in the proposed SAA project... Interchange Muiderberg (A1xA6):  Intechange Diemen (A1xA9):  NW Corner:  SW Corner:  NE Corner:  Interchange Hogering (A6xS101 Almere):  Capacity-wise we're getting a 3+6+2+6+2 lane configuration (including merging and weaving lanes) between IC Diemen and the subsequent newly built Muiden diamond interchange. Note the yellow tidal lanes on the maps, during rush hour the busiest connection will get two more traffic lanes either from Almere/Hilversum to Amsterdam or vice-versa. It'd be a pretty luxourious drive
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Apr 19, 2010 13:36
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Oh, they're finally fixing up that area? Hadn't heard about it yet, very nice. At the moment it's far from a luxurious drive if you need to go south from Almere in the direction of Schiphol... There's traffic jams, cloverleafs, and that bit of A2 in the A9 to make it the worst part of any trip south for me 
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Apr 19, 2010 14:05
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Cichlidae posted:purple What are purple markers for? I don't think I've ever seen purple lines. quote:I'll ask my boss today (he's from Michigan) if he can add any details. Thanks! I appreciate you satisfying my curiosity.
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Apr 19, 2010 16:58
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Koesj posted:Funny to see such a thread pop up on SA, I guess there are transportation professionals and enthousiasts all around the web though. I'm currently interning at an engineering firm and as an economic historian I'm writing my thesis on the growth of the Dutch freeway network. I've immersed myself a bit in the 'roads community' and there's lots of discussion about roads and transportation going on in the relevant sections of skyscrapercity here, most Dutch-speaking road enthousiasts hang out on the wegenforum. That's amazing! Holland's roads have always fascinated me, and its urbanism in general, because it's so rare that a country actually creates new land. Those interchanges have some impressive capacity, even as much as our biggest roads in Connecticut. I can only imagine the design volumes approach 200.000 ADT. Do you know what year they're being designed for? I've got to hand it to you folks: you know how to build roads. I also like learning Dutch. I assume "Kunstwerk" is the same as the French bridge term "Ouvrage d'Art"? ipbooks posted:What are purple markers for? I don't think I've ever seen purple lines. They're new in the 2009 MUTCD: purple lines and signs are to demarcate ETC (electronic toll collection) lanes, generally at toll booths. I know I'm not the only one who's had to swerve around a foggy toll plaza looking for the correct lane, so I'm hoping purple stripes get implemented soon. In theory, if you had a purple stripe at the edge of the road, you could put a purple delineator there. Not sure if anyone would do it in practice, as people might confuse it for Barney Pick-up Zone. ipbooks posted:Thanks! I appreciate you satisfying my curiosity. I edited the post to note that he has nothing to add, except that he wonders whether they're reflectorized. If they're not traffic control devices, they probably shouldn't be.
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Apr 19, 2010 21:59
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Cichlidae posted:That's amazing! Holland's roads have always fascinated me, and its urbanism in general, because it's so rare that a country actually creates new land. Those interchanges have some impressive capacity, even as much as our biggest roads in Connecticut. I can only imagine the design volumes approach 200.000 ADT. Do you know what year they're being designed for? I've got to hand it to you folks: you know how to build roads. I also like learning Dutch. I assume "Kunstwerk" is the same as the French bridge term "Ouvrage d'Art"? The planning horizon is somewhere beyond 2030 I gather. We might even be looking at the end state on this part of the corridor since a number of alternatives are being considered. It boils down to this: The A1 already carries 165.000 AADT and the future number is probably going to be north of 250k. Also, the city of Almere will double its number of inhabitants from 180k to 350k even though the country as a whole won't see any major population increase (on the contrary, they're predicting a decline after ~2025). So the dynamic northern part of the Randstad Holland ('Noordvleugel') will grow even more important, both economically and in demographics. There's a number of vague plans and studies in the pipeline which should deal with these developments during the coming decades. These are mostly based on cancelled corridors from the 1966 scheme and the 1968 freeway plan but might not see daylight in the non-permissive legal and legislative environment. Since these barriers have been put up from 1973 onwards it sometimes feels like we've actually forgotten how to build good roads in this country  Maintenance isn't an issue though, they're always aiming for the highest standards cause the entire network is so heavily used - stretches of 2+2 freeways carry 130k AADT and 3+3 freeways carry 180k, even 'rural' highways (a myth in this country) often carry more than 100k.Good call on the 'kunstwerk' translation, funnily enough you're probably more aware of the jargon than 95% of the Dutch population. They'd consider 'kunstwerken' works of art.
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Apr 20, 2010 13:09
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Getting away from highways, there's a project near where I live that I'd like to hear your opinion on. Here's the section on Google Maps. I don't know if there's anything you can say about it; I'm mostly just kvetching about it. As you can see, traffic comes from the city center to the West and passes over three bridges to clear the island in the middle of the river. All three bridges are problematic: the Neue Strombrücke has problems with its eastern foundation, so it's currently reduced to one lane + tram in the middle. The Zollbrücke is very narrow and only has one lane each direction which it shares with the tram line. I regularly find car drivers trying to slip onto the bridge in front of the tram and forcing the tram to brake sharply, though fortunately there haven't been any serious accidents there in recent memory. More importantly, this bridge is under pretty harsh heritage protection, which means the structure can't be messed with - it's even still got cobblestones as road surface, which of course make a lot of noise when cars drive over them. It is a fairly serious chokepoint on this route. The Anna-Ebert-Brücke is in okay condition but also quite narrow. All of this runs okay in normal traffic, but events regularly screw it up. The road that goes North just West of the Zollbrücke leads to the city's biggest concert hall, and there's fairgrounds down there, too. Any special event and the whole road backs up something fierce. Further to the East of this is another hall and our main soccer stadium, so that also generates substantial traffic. Now, in theory, all traffic passing through West to East and vice versa is supposed to take this set of bridges further North, which is built with two lanes and generally has acceptable traffic flow. The problem is that the sucky road near where I live is the shortest route (and in the case of the concert hall and fair grounds, the only route), and consequently a lot of people use it. The city, in its infinite wisdom, is considering a plan to remedy this. Their plan is to lenghten the Neue Strombrücke eastward and extend two new bridges to cross the river, bypassing the current narrow bridges completely for East to West traffic. Due to height differential, that means a large earthen mound would have to be created South of the current road to carry the new route about 5 meters above ground level. This new route would have one lane in each direction, plus the tram line in the middle. To summarize the problems with that: 1) The Neue Strombrücke will be fixed, but the second lane it has will disappear on the new bridges, so that's merging problems ahead. (We already have that now, but I don't see a good reason to carry it forward.) 2) The mound would basically kill the sightline into the park South of it. 3) Said park is also under EU habitat protection, so building around that is gonna be a headache. 4) The biggie: the new tram station will sit on that mound. To brave the height differential, they've proposed a ramp, but given the large amount of old folks who live here, that's gonna suck a lot for them. Apparently, elevators are out of the question due to vandalism concerns (?!). 5) Traffic connection for everyone living on the island. To go West, we'd use the Zollbrücke and merge into the new route essentially where the road to the concert hall is now. To the East, however, the new route would eliminate the intersection between Turmschanzenstraße and Brückstraße, so we'd go Anna-Ebert-Brücke, turn North onto Turmschanzenstraße and then go around there. Not exactly a direct route. 6) And of course, costs. Apparently we can get the initial efforts funded, but nobody has any idea what this will cost in upkeep. One counter-proposal to this problem I've heard frequently is to loosen heritage protection on the Zollbrücke and modernize it, maybe run a second bridge parallel to it and just widen the existing route. It's tight, especially with the descending road going into the park to the South, but I think it might be possible. The city isn't entertaining that, however, and in general they seem to be fairly committed to deciding first and informing us later. Anyway, kvetch over, European cities are built narrow and tight, old people don't appreciate being told to walk up long ramps, developing a historically-grown transport network is hard.
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Apr 20, 2010 13:35
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Would this be a good place for a roundabout? Or some other design? http://maps.google.com/?ie=UTF8&ll=...,102.88,,0,3.37 Basically: 23 is a pretty major cut-through for north county traffic going to US 1, 24 is a fairly major local road, and most of the traffic is straight through in all directions. 23 is a 55mph all the way up to the light then it turns into 40 or 35 until it hits 1, and I think 24 is a 35 in that area. There's another roundabout about 1.2 miles west of the intersection on 23 that only seems to go into a single business (google maps hasn't even been updated with it and it's been there nearly a year) so obviously they had no qualms about slowing down 55mph traffic so some trucks can turn left. I'd ask you about that too if it was on the map, surely a jughandle or something else would've done better there. The main problems are there's no left turn phase from 23 EB onto 24, and some days it's actually enough traffic waiting to turn left that it backs up into the single-lane stretch. Aside from the shopping center on the SE corner there's not much else around so it looks like there's plenty of room to do something with it. I guess one solution is just to put a left turn phase on 23 EB. At first I was thinking a roundabout might get complaints from the shopping center because traffic wouldn't be stopping and possibly going into it, but then I looked around a little and saw the only access is from 24 south of the intersection, so it might actually increase customers there (as thru traffic on 23 doesn't even see an entrance).
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Apr 20, 2010 19:50
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Koesj posted:It boils down to this: The A1 already carries 165.000 AADT and the future number is probably going to be north of 250k. Wow, that's massive. The freeway I built in France was made for a design volume of 9 000, which doesn't even merit a four-lane surface street in the US. We plan for 2030 as well, by the way. Koesj posted:Good call on the 'kunstwerk' translation, funnily enough you're probably more aware of the jargon than 95% of the Dutch population. They'd consider 'kunstwerken' works of art. I knew my experience over there would come in handy for something. Eventually, I hope to move back to the EU and get a nice job there. Gatac posted:Die Zukunft der Elbebruecken If it were up to me, I'd go with a 2x2-lane + tram extension of the Neue Stormbruecke on piers, not embankments, to avoid a couple of those problems. Unfortunately, it'd also be quite a bit costlier. The cheapest option that would solve a bunch of problems would be to just close the Zollbruecke to vehicular traffic, making it pedestrian-and-tram only. It would encourage (well, mandate, really) drivers to use the other bridge North of there. Of course, I'm sure the public reaction would be negative, and it would increase traffic somewhat overall. But hey, it's cheap!
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Apr 20, 2010 22:12
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Roflex posted:Would this be a good place for a roundabout? Or some other design? If they put a roundabout at the intersection of a medium-volume, high-speed road and a single business, it's likely that the objective was traffic calming, not producing gaps. Roundabouts actually have the negative effect of removing/smoothing out gaps, and slowing most of the traffic from 55mph to 15mph wastes a lot of energy. Roflex posted:The main problems are there's no left turn phase from 23 EB onto 24, and some days it's actually enough traffic waiting to turn left that it backs up into the single-lane stretch. Aside from the shopping center on the SE corner there's not much else around so it looks like there's plenty of room to do something with it. I guess one solution is just to put a left turn phase on 23 EB. Since the left turn lane is already so long, it's possible that the volumes are too high for a single-lane roundabout. In that case, if you really think you have good drivers, you could go for a two-lane or turbo roundabout. Otherwise, revising the signal to add left-turn phasing could be done for a tenth the cost and work just as well. Of course, if the town wants traffic calming, you can expect a chain of roundabouts on either side of the signal at each side street. The signal gets a left turn phase, cars are slowed down, there's a reduction in accidents at the intersections, everyone wins... except those of us that would prefer to actually get somewhere at a decent speed.
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Apr 20, 2010 22:22
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Hot poo poo, is it really that time again?! Work Zone Safety! Ima and Tyler explain the importance of safety at rail crossings. Tyler, unfortunately, had a mishap at a rail crossing in his youth. He was bonked on the head by the gate arm, and he is no longer able to use question marks. Prognosis is... questionable  Since Ima mentioned at-grade rail crossings, I'd like to note that I have in my hands a railroad safety booklet!  Well, HAD, but my wife snatched it up and is currently busying herself with coloring it and answering all the questions within. More on that later, though, because Tyler has something to tell us! What's that, Tyler?  Tyler explains once again that yellow = mellow. Coloring book, or soft drink advertising campaign in disguise?! Furthermore, it seems that someone took advantage of his vulnerable mental state to convince him that inanimate signs have the ability to walk across the road. Well, then again, he is inanimate himself, and he's talking... this booklet is deep, man. Deep.
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Apr 21, 2010 00:45
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Cichlidae posted:Is that yellow-green thing true? I've only ever seen them in yellow.
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Apr 21, 2010 04:26
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Well here's one I'm pretty use to. Auckland's central motorway junction (Colloquially known an spaghetti junction). It use to be a lot worse, with a few right exiting off ramps and on ramps (We drive on the left remember). http://maps.google.co.nz/?ie=UTF8&ll=-36.857871,174.760723&spn=0.013941,0.01929&t=k&z=16 Enjoy! (Im not really asking if you could improve it - Im posting just so you can stare in wonder)
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Apr 21, 2010 06:12
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Nibble posted:Is that yellow-green thing true? I've only ever seen them in yellow. It was provisionally approved a few years ago, and now the new MUTCD recommends FYG (Fluorescent Yellow-Green) at all school-related warning signs. You can also use it for pedestrian signs in general, but most states don't want to do that. The novelty of the FYG signs makes them stand out. This effect is probably temporary; once more people get used to the color, they'll be treated the same as any other sign. For now, though, they're pretty shiny, and people pay a lot of attention. Jvs_NZ posted:Looks like finding space was the main constraint here. If a highway engineer has a choice between putting in a right entrance and knocking down a few houses, his life starts to get pretty complicated. What's the deal with that half-interchange with Union Street to the north? It looks like it was designed with huge volumes in mind.
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Apr 21, 2010 12:38
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 I'm confused. The silhouette isn't one of the standard ones in the Vehicular Traffic or Nonvehicular Traffic sections of MUTCD 2009, and since I'm at an intersection and he's wearing a seatbelt, shouldn't I be checking all approaches for him anyway? As far as the anal probe finger, that seems like something the Department of Health should be warning me about, not the DOT. He looks kind of like the "Seat Belt" symbol in figure 2B-22, but they say you can only make "Minor modifications" and I wouldn't consider an anal probe very minor. Then there's the text. "Be Progressive" is a bit political for a warning sign, isn't it? I know we need to be respectful of other drivers, even if they are non-humans waving their probes at us menacingly, but wouldn't a W16-1 (vertical rectangle, text "SHARE THE ROAD") get the point across just as clearly and without the unauthorized use of italics? http://maps.google.com/maps?ie=UTF8...,237.55,,1,4.07
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Apr 21, 2010 18:47
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GWBBQ posted:
Dunno if this is a seriouspost but It's a sign that's a throwback to the old Progressive commercial that aired during the Super Bowl (I believe) that had E.T. telling people to Buckle Up. I have a couple around where I live, and I wonder how they stay, as they're basically marketing signs on official signposts. I guess it was smart because what government would say "Take down that offensive sign that tells people to buckle up"
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Apr 21, 2010 21:18
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GWBBQ posted:
BRB, gotta grab my sledgehammer and drive down to Berlin... I can abide by all of those transgressions, but the fact that it's mounted below 7' and on the same post as a regulatory sign is just too much. Edit: Actually did drive down to Berlin, but I got distracted by Job Lot and ended up buying a body pillow. drat! Cichlidae fucked around with this message at 22:49 on Apr 21, 2010 |
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Apr 21, 2010 21:45
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Cichlidae posted:What's the deal with that half-interchange with Union Street to the north? It looks like it was designed with huge volumes in mind. Yup. That interchange is for the on and off ramps for the southern and western motorways - basically it feeds traffic for the majority of the CBD travelling to/from the south and the west. So it feeds more than half of the greater city's (Pop. 1.4 million) access into the central city. The satellite photo shows the ramp signalling in action just to the left of the interchange. This is the main thorough fair for the western motorway to join the northern (We are original with our motorway names here). You can see the main motorway flowing pretty freely while the on-ramp is backed up. AFAIK, every interchange on Auckland's motorway system now has these on-ramp lights. They aren't dumb lights, and are controlled by the control office as well as sensors on the motorway. The phasing time changes dependent on how busy the motorway is. If it's reasonably light the lights will let through a car every 2 or 3 seconds. If the motorway is congested its more like every 10 seconds. If the motorway is blocked up like a bitch, then the lights are turned off because they are ineffective at that stage. Jvs_NZ fucked around with this message at 00:39 on Apr 22, 2010 |
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Apr 22, 2010 00:37
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Cichlidae posted:BRB, gotta grab my sledgehammer and drive down to Berlin... I can abide by all of those transgressions, but the fact that it's mounted below 7' and on the same post as a regulatory sign is just too much. We have one of these on my hill in Thomaston. It's on the same post as a regulatory sign below 7' as well.. I think it's my civic duty to take it down
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Apr 22, 2010 00:43
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Jvs_NZ posted:AFAIK, every interchange on Auckland's motorway system now has these on-ramp lights. They aren't dumb lights, and are controlled by the control office as well as sensors on the motorway. The phasing time changes dependent on how busy the motorway is. If it's reasonably light the lights will let through a car every 2 or 3 seconds. If the motorway is congested its more like every 10 seconds. If the motorway is blocked up like a bitch, then the lights are turned off because they are ineffective at that stage. That's the way to do it. Ramp metering isn't very effective unless it's used extensively. If every on-ramp has signals, it's theoretically possible to keep a freeway running at maximum flow even though demand far exceeds capacity. Of course, the ramps will back up, but it's better to be stuck in a 5-minute queue on a 200-meter ramp than a 30-minute queue on a freeway. Of course, things get tricky when you have freeway-freeway junctions. If the volumes are volatile, you can end up over capacity in spite of the meters. The City of Phoenix, in its infinitesimal wisdom, decided to put ramp meters on freeway-freeway ramps. Here is one. Ever wonder what it's like being rear-ended at 70 mph by people who don't expect to find stoplights in the middle of freeway ramps? Fizzle posted:We have one of these on my hill in Thomaston. It's on the same post as a regulatory sign below 7' as well.. I think it's my civic duty to take it down I think I should take a wrench with me into the field from now on and start a collection of pirate signs. Not sure what I'd do with them, but if people can cover their houses in old license plates, why not illegal signs?
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Apr 22, 2010 01:24
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Cichlidae posted:Of course, things get tricky when you have freeway-freeway junctions. If the volumes are volatile, you can end up over capacity in spite of the meters. The City of Phoenix, in its infinitesimal wisdom, decided to put ramp meters on freeway-freeway ramps. Here is one. Ever wonder what it's like being rear-ended at 70 mph by people who don't expect to find stoplights in the middle of freeway ramps? That was probably ADOT instead of COP, and the only reason they "get away with it" is as far as I can tell, they consider SR143 a freeway only when it suits them, and 48th Street when it fits their need. To be fair, 143 is only a few miles long and is one of the few freeways that is actually a 55 limit instead of a 65. It also pretty much only exists to feed Sky Harbor. SR153 technically did as well, but it saw such low volume (mostly because despite being a divided highway, it doesn't intersect any other divided highway directly) that ADOT gave it back to Phoenix and it's been 44th Street for a few years. The whole 143/153 pair is kind of a clusterfuck, anyway. The only well-designed bits are the SPUIs at 143/University and 143/Washington. Besides, the ramp at the other end of the 143, to 10E, is worse. It backs up all the way to University some days, and has people weaving in and out of it along that whole mile-long lane leading into it to try and cut other people off, because the two lanes that don't go onto the freeway are nearly deserted by comparison.
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Apr 22, 2010 01:34
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IOwnCalculus posted:The whole 143/153 pair is kind of a clusterfuck, anyway. The only well-designed bits are the SPUIs at 143/University and 143/Washington. I found it really astounding that, in the "best-run city in the world", which is in most ways thoroughly modern and has only existed in the age of freeways, there's a pair of dead-end freeways that come within a couple hundred feet of each other and don't have a single interchange in common. Field Trip! Today, the weather was good, so I went out to Pomfret and Killingly. Pomfret, if you're not familiar with the town, is a stereotypical pastoral New England paradise. Lots of small farms, beautiful old colonial architecture, and tremendously scenic countryside. Here are a few photos I snagged from Photolog to show you; I couldn't take them myself since I was busy driving.         See? Pomfret's a perfect place for a traffic engineer to retire. Anyway, the project in question is a bridge on US 44. 44 is a busy road for much of its length, but here, 40 miles from Hartford, you'll only see a couple cars each minute.  The project is immediately adjacent to Connecticut's most confusing bird sanctuary.  Well, frankly, the bridge doesn't look so bad. Lanes are a little narrow, sure, and that guard rail's not in great shape, but at least there's not a 4-foot hole in the deck. Let's have a gander at the underside.  Oh, I see. Replacement it is!  There's a graveyard immediately adjacent to the bridge, so the construction workers will be kept company by some 200-year-old corpses. Now, it's up to me to choose whether to close the bridge and make a detour, or try for alternating one-way traffic. Volumes are still enough that alternating one-way traffic can be a pain. We have a similar situation right down the road, though, and decided to use a new sign:  Surprisingly, it seems to work. People up in this part of the state are much calmer and less aggressive than the city drivers. While I was there, they paid attention and went by in groups of three, and queues stayed very small. Moving three cars at a time is maybe twice as efficient as normal stop-controlled alternating one-way, which can only handle 750 vph bidirectional. After Pomfret, it was off to Killingly to see how construction is going. Here's pretty much the extent of it:  Looks like they're still waiting on the utility companies to come move the poles. Utilities are notoriously slow, because they have no financial impetus to follow the contractor's schedule. We don't even get pole relocation plans during design, which ended up being a big problem on this particular project. I had to redesign the signal span at the last minute to avoid a potential utility conflict.  And there's our last non-congested interstate. Looks so peaceful, doesn't it? For a freeway built over 40 years ago, I-395 is still in good shape.
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Apr 22, 2010 02:41
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