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EoRaptor posted:The biggest issue with these types of stimulus plans is that they are patch jobs. They don't drive demand for anything but direct labour jobs, and fail to create the need for higher education and management jobs that help expand the middle class. This isn't a dig against Cichlidae or his coworkers, but this type of spending doesn't create need for any more of them, so it doesn't drive growth in higher education and better prospects. BBC posted:Mr Obama also called for the creation of a permanent infrastructure bank that would focus on funding national and regional infrastructure projects.
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Sep 7, 2010 22:06
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Hey OP I used to do concrete demo and refurbishment of bridge decks and every now and then we'd get to wondering what y'all were thinking. Now I know. Your thread is cool as hell and thanks for putting all this work into it.
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Sep 8, 2010 00:48
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Nesnej posted:I like to see this idea gaining traction. Infrastructure needs longer funding periods than single budget years. I just hope it has guidelines to maximize long term utility and benefit of what it funds, because these types of funds often end up being horribly broken in practice (see the bus rapid transit fiasco). Maybe they'll buy a million of these: http://www.good.is/post/vancouver-s-new-speed-bumps-little-children
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Sep 8, 2010 02:32
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FedkaTheConvict posted:Hey OP I used to do concrete demo and refurbishment of bridge decks and every now and then we'd get to wondering what y'all were thinking. Now I know. Your thread is cool as hell and thanks for putting all this work into it. Glad I could help! We probably don't think of how easy a bridge will be to demolish as much as we should; it's hard enough to get it up in the first place. Some of our bridges were built with some extra width to facilitate staging for future construction/maintenance/replacement, but that seems to be the exception these days. EoRaptor posted:I just hope it has guidelines to maximize long term utility and benefit of what it funds, because these types of funds often end up being horribly broken in practice (see the bus rapid transit fiasco). We really need engineers to decide our infrastructure policy, and not politicians. Most elected officials only seem to plan from one election to the next. Roads are inherently a decades-long investment; railroads, centuries. quote:Maybe they'll buy a million of these: I doubt anyone will notice these anymore after the fourth or fifth time they drive over it. It might even lead them to pay less attention to the road, as a child doesn't stand out as much. Not to mention that maintenance costs would be a nightmare. I liked Costa Rica's strategy of painting a heart on the ground everywhere a pedestrian was killed. They're not frequent enough to confuse drivers, and certainly not complicated enough to make someone who's not paying attention swerve, but they're an excellent reminder to slow down.
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Sep 8, 2010 03:25
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Cichlidae posted:I liked Costa Rica's strategy of painting a heart on the ground everywhere a pedestrian was killed. They're not frequent enough to confuse drivers, and certainly not complicated enough to make someone who's not paying attention swerve, but they're an excellent reminder to slow down.
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Sep 8, 2010 03:28
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smackfu posted:In a few countries, I've seen where they put up permanent shrines where there was a roadside accident. Like little dollhouses with a photo in it and a cross on top. Some of the bad curves would have a dozen of them; it sure made me slow down. This definitely happens in the US too.
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Sep 8, 2010 04:08
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theflyingexecutive posted:This definitely happens in the US too. http://en.wikipedia.org/wiki/Ghost_bike
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Sep 8, 2010 04:45
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EoRaptor posted:I just hope it has guidelines to maximize long term utility and benefit of what it funds, because these types of funds often end up being horribly broken in practice (see the bus rapid transit fiasco). loving moronic idea. Let's program people to ignore things that look like children in the street...
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Sep 8, 2010 07:21
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Speaking of speed bumps, do you use the turtle speed bumps in the US? They look like this, though usually a bit more raised up:  The basic idea is that busses and emergency vehicles (and I suppose, other vehicles with a wider wheelbase) can drive over the bump without slowing down but normal cars have to come almost to a complete stop if they dont want to wreck their cars.
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Sep 8, 2010 15:23
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MrBling posted:Speaking of speed bumps, do you use the turtle speed bumps in the US? My city is actually installing a similar setup they refer to as speed cushions.  They aren't as brutal as the ones you've just posted so they only post about an 8mph decrease in speed, but they do let emergency vehicles get through at full tilt.
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Sep 8, 2010 17:43
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MrBling posted:Speaking of speed bumps, do you use the turtle speed bumps in the US? They're hilarious in rental cars or SUVs, though 
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Sep 8, 2010 18:36
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IOwnCalculus posted:My city is actually installing a similar setup they refer to as speed cushions. http://maps.google.com/?ie=UTF8&ll=...300.67,,0,27.12  The ones on this road for some reason are really brutal, and I can't take them faster than ~10mph. My next car is going to have to have a wider wheelbase I think.
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Sep 8, 2010 20:26
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EoRaptor posted:
I saw someone with the idea of projecting a cop car instead. Sometimes, it will be a real cop. That way you will be kept on your toes. Maybe you could speed actuate it too.
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Sep 8, 2010 22:27
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MrBling posted:Speaking of speed bumps, do you use the turtle speed bumps in the US? IOwnCalculus posted:My city is actually installing a similar setup they refer to as speed cushions. I'm not a big fan of any kind of vertical curvature that forces traffic to slow down. We have to design for the worst driver, and that includes people who will drive too fast over everything. I'd much rather introduce subtle horizontal curves or narrow the lanes, which are more forgiving and won't snap your neck if you aren't paying attention. Speed cushions and turtles certainly do appear to solve the emergency vehicle problem, though. If a municipality is dead set on putting in bumps, may as well do it right! grnberet2b posted:he ones on this road for some reason are really brutal, and I can't take them faster than ~10mph. My next car is going to have to have a wider wheelbase I think. And this may be an unintended consequence thereof. Guy Axlerod posted:I saw someone with the idea of projecting a cop car instead. Sometimes, it will be a real cop. That way you will be kept on your toes. Maybe you could speed actuate it too. Believe me, that'll get smashed within a week. When they try putting out cardboard cutouts of troopers or unmanned police cars, people catch on quickly and sabotage them. All it takes is one angry guy with a crowbar at 2 am and your $10,000 cop projector is toast.
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Sep 9, 2010 00:08
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Cichlidae posted:I'm not a big fan of any kind of vertical curvature that forces traffic to slow down. We have to design for the worst driver, and that includes people who will drive too fast over everything. I'd much rather introduce subtle horizontal curves or narrow the lanes, which are more forgiving and won't snap your neck if you aren't paying attention. You know what's fun? The speed tables on Prospect Avenue in Hartford. Especially because they're about a car length and one is at the bottom of a longish hill. The first time I went over one of those, I was with my dad in his Ford E150. "Is that a crosswalk? I think it's a-" FWA-BUMP "...crosswalk." Took it at like 30mph. Quite fun.
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Sep 9, 2010 00:19
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They have speed humps in a few places around here and they were pretty much the best part of driving in the two cars I had with air suspensions. Slow to 10mph? Hell no, up to 35, float over in the town car, see if I can get some rear wheel hop and leave tire marks on it in the Mark VII. Without those, I would have just gone the speed limit on those roads, but they made it so much fun.
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Sep 9, 2010 01:33
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Derpes Simplex posted:You know what's fun? The speed tables on Prospect Avenue in Hartford. Especially because they're about a car length and one is at the bottom of a longish hill. The first time I went over one of those, I was with my dad in his Ford E150. The have those in Windsor leading up to Northwest Park. They're marked with signs that say Speed Humps. I chuckle every time I see them.
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Sep 9, 2010 01:45
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I had some free time today, so I made this and slipped it in the Busway project folder:  FDP = Final Design Plan, when the 100% submission is complete. This date keeps getting shifted as the schedule changes. DCD = Design Completion Date, when the project is ready to be advertised and won't change anymore. Still not sure when this will happen. Derpes Simplex posted:You know what's fun? The speed tables on Prospect Avenue in Hartford. Especially because they're about a car length and one is at the bottom of a longish hill. The first time I went over one of those, I was with my dad in his Ford E150. Do you live in the area? If so, I've got plenty of projects you might be interested in.
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Sep 9, 2010 02:11
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Cichlidae posted:Do you live in the area? If so, I've got plenty of projects you might be interested in. Attend school in the area, actually, though I grew up along Route 8.
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Sep 9, 2010 02:17
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Cichlidae posted:I had some free time today, so I made this and slipped it in the Busway project folder: hahaha this is amazing!
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Sep 9, 2010 03:54
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Up here in Minnesota, I just noticed some new traffic signals going in, a flashing yellow arrow. I don't get what the difference between a flashing yellow arrow than those that have a yielded left turn on green. Here's the link to Minnesota's DOT. http://www.dot.state.mn.us/trafficeng/signals/flashingyellowarrow.html
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Sep 9, 2010 23:28
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golfem posted:Up here in Minnesota, I just noticed some new traffic signals going in, a flashing yellow arrow. I don't get what the difference between a flashing yellow arrow than those that have a yielded left turn on green. Here's the link to Minnesota's DOT. http://www.dot.state.mn.us/trafficeng/signals/flashingyellowarrow.html I like that idea. Around here, if you get a green arrow at a light, it means you only get to go on the protected-left phase; you have a red arrow at all other times, even at times of day / night when you can easily make a left without protection.
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Sep 10, 2010 00:00
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They solved this problem in NY by making the cycle: Green Arrow Yellow Arrow (End of protected Left, Start of permissive left) Green Ball Yellow Ball Red Ball I'm not sure what I would prefer.
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Sep 11, 2010 14:15
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Guy Axlerod posted:They solved this problem in NY by making the cycle: They've done that everywhere I've lived, though I'm used to seeing intersections that do not have a permissive left phase at all.
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Sep 11, 2010 14:22
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Just need to rage for a moment... A town nearby just repaved a road by throwing down a thin layer of asphalt on either lane, leaving a huge gap of older, lower pavement that ranges randomly from a few inches to a few feet (passive-aggressive towards motorcyclists, are we?). Its been like that for almost two weeks. The new pavement isn't smooth by any means, and looks like total rear end. I'm not sure if this is better than their chip sealing jobs which inevitably end up with huge patches of traction-free oil where there was once asphalt. I'm sure they'll either pave the street again for real, then immediately chip seal it so it can quickly wear down and be dangerous once more. or simply chip seal what's there now and call it a day. OK, I'm better now.
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Sep 11, 2010 19:07
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Citizen Z posted:They've done that everywhere I've lived, though I'm used to seeing intersections that do not have a permissive left phase at all. Protected-only is pretty common up here on arterials, but we actively try to use protective-permissive when possible, including signing a through lane as a right-turn lane. We know most people will still use it as a through lane, but now there are only two lanes opposing the left turn, not three, and permissive is ok. Crackpipe posted:Just need to rage for a moment... Somewhere is a fresh new road, paved 18" deep with solid Superpave 0.375" and waiting for you. When you find this bituminous nirvana, you will forget all of your past tribulations and learn the true meaning of zen.
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Sep 11, 2010 21:32
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A couple places around here recently went to flashing red (i.e. left turn after stopping) where there's two left turn lanes. Actually one of the places has been like that as long as I can remember (20+ years) but the other few were part of a recent overpass reconstruction. What's required for that to be allowed? I'm asking because they recently turned a permissive left single left into a phase-separated double left near me and it means I have to wait for a full cycle coming home at 3am, sometimes as long as 6 minutes, to turn left into my neighbourhood.
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Sep 11, 2010 23:15
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Roflex posted:A couple places around here recently went to flashing red (i.e. left turn after stopping) where there's two left turn lanes. Actually one of the places has been like that as long as I can remember (20+ years) but the other few were part of a recent overpass reconstruction. What's required for that to be allowed? I'm asking because they recently turned a permissive left single left into a phase-separated double left near me and it means I have to wait for a full cycle coming home at 3am, sometimes as long as 6 minutes, to turn left into my neighbourhood. First off, if the cycle length is 6 minutes, that's really excessive. Anything above 120 seconds is going to operate badly; 60-90 is ideal. For left turn on red, that's not something we have here, and I don't think we'd ever consider it. People here aren't familiar with that type of indication. Therefore, I can't tell you what kind of situation would warrant it. I can see it being used when overnight volumes are low, but we usually just set the whole signal to flash in that case.
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Sep 12, 2010 00:26
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Crackpipe posted:I'm not sure if this is better than their chip sealing jobs which inevitably end up with huge patches of traction-free oil where there was once asphalt. I'm sure they'll either pave the street again for real, then immediately chip seal it so it can quickly wear down and be dangerous once more. or simply chip seal what's there now and call it a day. Cichlidae posted:First off, if the cycle length is 6 minutes, that's really excessive. Anything above 120 seconds is going to operate badly; 60-90 is ideal.
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Sep 12, 2010 04:08
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GWBBQ posted:Do they at least run a steamroller over it when they're done? Fairfield did another road a few weeks ago where they just dumped rocks and called it a day. I drove down a road in Middlefield with the same thing. They put up orange signs that said "Loose rocks 15 mph" every few hundred feet. It's not often I get the chance to take my car off-roading. quote:Oh, so that 12 minute (according to city traffic guys) wait for a left turn arrow into UCONN Stamford's garage when I was a student wasn't standard? Heck no; sounds like they had a grudge against students. 12 minutes, barring extraordinary few-times-a-year situations, is just nuts. I got pretty uneasy just seeing traffic cops hold one phase for 5 straight minutes in Manchester last week, and that was just a one-time thing. You make anyone wait for 12 minutes, and your level of service is completely shot.
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Sep 12, 2010 15:35
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Basically, unless there was a cop sitting there, the light was optional. They changed it to 3 minutes max once it senses a car in the left turn lane, which only feels like 10 minutes when there's no oncoming traffic, especially if I was late for class.
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Sep 12, 2010 16:37
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It's a really high volume road against another nearly-as-high volume road, and the cycle lengths are the same regardless of time of day or traffic conditions, even though they just re-did the whole intersection. I think something might just be wrong with the way it's programmed since they also installed sensing cameras (the intersection gets dug up 3-4 times a year due to water main breaks so there's no in-pavement sensors). Once in a while I'll get an early green but it's very rare. Six minutes might just be "it's 3am and I just want to get home" bias but it's about 2 minutes for the through phase on the main-er road, and a minute to a minute and a half for each direction on the other road (each is a separate phase). This is one of the places where there's left-on-flashing-red (not on solid red) with 2 left turn lanes. It's also really close to a fairly hosed-up offramp. e: Here's another. They're not extremely common but they do pop up in quite a few places around here. Xerol fucked around with this message at 16:52 on Sep 12, 2010 |
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Sep 12, 2010 16:46
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Roflex posted:It's a really high volume road against another nearly-as-high volume road, and the cycle lengths are the same regardless of time of day or traffic conditions, even though they just re-did the whole intersection. I think something might just be wrong with the way it's programmed since they also installed sensing cameras (the intersection gets dug up 3-4 times a year due to water main breaks so there's no in-pavement sensors). Once in a while I'll get an early green but it's very rare. Six minutes might just be "it's 3am and I just want to get home" bias but it's about 2 minutes for the through phase on the main-er road, and a minute to a minute and a half for each direction on the other road (each is a separate phase). It's strange that they wouldn't use a different timing plan for off-peak hours. Even our relatively minor signals here usually have 3 different timing plans set up for morning peak, afternoon peak, and off-peak hours. Cycle lengths are much shorter in off-peak times to keep delays and queues low. quote:This is one of the places where there's left-on-flashing-red (not on solid red) with 2 left turn lanes. It's also really close to a fairly hosed-up offramp. At least they have a sign to explain what the flashing red arrow means. The off-ramp isn't all that bad; teeing it up with the side street would be preferable these days, but the design is meant to prevent wrong-way entry onto the freeway.
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Sep 12, 2010 17:55
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Cichlidae posted:traffic cops hold one phase for 5 straight minutes in Manchester last week  (Just to add some text: What'd they do that for?)
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Sep 13, 2010 02:00
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GWBBQ posted:Do they at least run a steamroller over it when they're done? Fairfield did another road a few weeks ago where they just dumped rocks and called it a day. I think they do steamroll the street now, but the asphalt suffers from so many cracks and frost-heaving that it'll probably accelerate the decay. Whoohoo! At least they don't use twice as many rocks, like the used to. When I was little, there were rock drifts on the side of the road, and the plants looked like BP had started doing roadwork.
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Sep 13, 2010 05:57
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Choadmaster posted:
The project's a road realignment at East Catholic High School and Cheney Tech. Temporary signal in place, all fixed-time since the loops were ripped up. The signal works beautifully for 22 hours a day. The only issue is at 7 am and 3 pm, when there's a sudden rush of teenagers driving Escalades and S-classes entering/leaving East Catholic, combined with schoolbuses for Cheney Tech. Since the signal has to run the same cycle all day long, with no actuation, it's a compromise between screwing over the arterial during the off-peak hours, or screwing over the school driveways during the peaks. We put a cop out there for the first week to ease the transition. I went out to the field with my co-worker to see whether we could adjust the timings to give a bit more time to the East Catholic driveway, since we were getting a lot of complaints. We asked the cop to just stand by for a few cycles so we could see how things work with just the signal in place. Utilities were out there working, as well, with their own set of cops, so it wasn't exactly unhindered traffic. Can't have everything, right? Turns out, almost everyone coming out of the driveway is on a phone, putting on makeup, or otherwise not paying attention, even with the cop sitting right there. When the light turned green, they'd just sit for a few seconds. And they almost never took a right turn on red, despite the fact that roughly 80% of the traffic was turning right and they could've moved a considerable volume of traffic if they'd just gone. Eventually, we'd seen what we needed to see, so we asked the cop to let some cars out of the driveway. We were expecting he'd let them go for maybe 30 second, a minute, tops, but he just stood there, waving those confused soccer moms and trust fund babies on for five straight minutes. The artery backed up to Cheney Tech, which was letting out at the same time, and almost all the way to I-84. Ouch. Then, the cop let the artery go for a minute or two, and gave East Catholic another 5-minute interval! That cleared out all of the cars, but he kept waving them on, even when there were none left. We added a new controller to the temporary signal, as well as a lead left into the driveway, so that should help things somewhat. The wait getting out of East Catholic is still a half hour. We're getting a ton of complaints. But hopefully they'll realize, in time, that at least everyone gets to move once a minute, instead of being stuck there for 5 while another street gets the green. ...Nahhhh, who am I kidding?
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Sep 13, 2010 12:47
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Ran out of lowercase C's, eh? (I love how I can look poo poo up on Google Streetview, even though their image quality is kind of lovely.)
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Sep 13, 2010 14:20
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smackfu posted:Ran out of lowercase C's, eh? By reusing old sign lettering, we can save the average taxpayer 0.018 cents/year! ConnDOT: Big letters, tiny budget.
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Sep 13, 2010 17:11
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Cichlidae posted:It's strange that they wouldn't use a different timing plan for off-peak hours. Even our relatively minor signals here usually have 3 different timing plans set up for morning peak, afternoon peak, and off-peak hours. Cycle lengths are much shorter in off-peak times to keep delays and queues low. Has there even been research done on abandoning the whole concept of a set cycle altogether and dynamically altering the signals based on detected traffic? I'm not talking about just one signal sitting there listening to the inductor loops embedded at that intersection, I'm talking about tying a network of signals together with wifi and having them keep track of the number of cars entering and leaving each intersection and signaling in order to maximize traffic flow. Seems like a very neural-net sort of optimization problem. There's one near me that pisses me off a *lot*. There's a busy intersection where you make a left onto the main road, you've got a lane with a permissive left turn lane. The cycle timing is such that if you make it through that lane after it's changed from green arrow to green, you end up at the red light at the next intersection down, which *isn't* busy, so there's no cross traffic anymore, but you still get to sit there for a couple of minutes of red while nobody approaches. And it has to do that, because if it stayed green traffic coming up the main road to the busy intersection would back up to and through the non-busy intersection. There's got to be some way to make those lights talk to each other so that areas like that aren't the cluster-fucks they are now.
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Sep 13, 2010 18:58
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One of the best things about being a near-graduation civil engineering student: companies showing off their best works to attract new young people. Today we visited a new and pretty cool project called the Westrandweg near Amsterdam. It's the dotted line in the picture. Now, per definition, if it's located around Amsterdam, the government spends a lot of money on every new project that has something to do with transportation. This project is no exception. The Westrandweg passes through some of Amsterdams busiest industrial zones. So, in order to reduce all noise and interference with regular traffic, the powers that be decided to build a 3.5 kilometer long fly-over. The longest fly-over in the Netherlands, with an average span of 40 to 45 meter and an average width of 25 meter. To make things more complicated, no mobile cranes can be used and all other traffic (including 6 railway tracks) must be able to use all existing roads while constructing the new Westrandweg. Sounds pretty much impossible right? Wrong.  Click here for the full 1600x1200 image.  Click here for the full 1600x1200 image. Westrandweg: 1 billion dollars. Some assembly required. Main assembly tool:  Click here for the full 1600x1200 image. This huge launch installation picks up a pre-tensioned concrete beam, then extends and lifts the beam to its intended position. They manage building speeds of one spanwidth every week. Incredibly fast, compared to traditional building methodes. The launch installation was built in Italy, specifically for this project. It's even larger than the picture makes it seem like. All beams are pre-fabricated and tensioned in a huge factory which I sadly wasn't allowed to take pictures of. You can take my word for it that it was pretty impressive though. They tension the beams with over 1200 N/mm of pressure to compensate for the weight of the deck and traffic. When the beam is finished they transport it to the building site at night. The concrete company had to build a ponton over a nearby river to get the beams on the road. I'll let the pictures do the rest of the talking.  Click here for the full 1600x1200 image. Fun fact: before the bridge deck is placed on the rubber beds, it rests completely on these simple wooden wedges. When construction nears completion, the wedges are wedged out and the deck moves to it's final resting place.  Click here for the full 1200x1600 image. Building a fly-over to heaven. When it's finished, 80.000 cars will drive here every day.  Click here for the full 1200x1600 image. The space between the beams is filled with concrete. After the concrete settles, all you need is a layer of asphalt.  Click here for the full 1600x1200 image. To give you an idea of the scale of the launching installation.  Click here for the full 1600x1200 image. You can see three remaining bundles of post-tensioning cables near the pillar, the rest have all been tensioned and cut off.  Click here for the full 1600x1200 image. Trains pass under the new fly-over at a rate of about 30-40 trains an hour.  Click here for the full 1600x1200 image. Not everything goes as flawless as you'd think though. Notice the huge piece of missing concrete near the tensioning cables. They never told us what happened though, looks like a collision of some sort. tl;dr: YAY ROAD TRIP 
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Sep 13, 2010 19:42
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