|
grover posted:Concrete mixing plants come on wheels, too! They recently opened up a big new stretch of highway near me. I'd occasionally drive by the big staging area and I remember seeing what kinda looked like a small concrete plant they built for the project. Handy for big stuff, I'd imagine.
|
#
?
Oct 3, 2013 13:47
|
|
|
|
| # ? Apr 28, 2024 06:17 |
|
|
True story: One of those little portable jobbies fell off the back of a pickup and clocked me on the head once. Concussions suck.
|
|
#
?
Oct 3, 2013 15:44
|
|
|
kefkafloyd posted:I just drove by it this weekend (the I-93 thing), it really is impressive, for a directional wye. Did you drive on the on-ramp itself or just past it? Feels like real life Need for Speed if you're going southbound from the mall.
|
|
#
?
Oct 4, 2013 05:03
|
|
|
dupersaurus posted:That ties into something I've wondered about before: how much does the local area's ability to produce asphalt and concrete affect the time you can build stuff in? For a big project, you build a concrete and asphalt plant somewhere nearby. On the A19, Eurovia built a really nice, full-size asphalt plant to pave the road when it was ready.
|
|
#
?
Oct 4, 2013 11:39
|
|
|
So no one likes this big new interchange in the city. It was built entirely for political reasons too, the signal was working fine for the fairly minimal traffic the airport gets. Most everyone agrees this is an over-engineered mess but most blamed "stupid north americans" for everyone's confusion about it, but I'm leaning more and more towards it just being a poo poo design. http://goo.gl/maps/7avbJ here's the interchange. And here's the article. http://www.timescolonist.com/steve-wallace-readers-weigh-in-on-mctavish-roundabouts-1.648955 Telling people to fly into another airport to avoid it is insane, but people experienced with driving in europe or the UK/Ireland all say it's poo poo too. It's hard to tell from the map but from my own limited experience with it, you have no idea what you're even driving towards until you're basically in it, and then you suddenly have to react to it. For a lot of people that aren't super comfortable with such systems, they panic and have no clue what to do. I've driven it a few times and still get pretty nervous some idiot is going to hit me, or I'm not in the right lane or what ever. There is no major growth planned for the area, no developments, just an airport with pretty flat traffic numbers that was served mostly fine by a signal. A very simple fly-over eliminating the left turn from the south would have been more than enough.
|
|
#
?
Oct 4, 2013 18:11
|
|
|
Roundabouts used to save a few ramps on highway interchanges are one of the worst things British road engineers ever made and exported. And here it looks like someone tried to do that, but then went and made even more anyway. It really looks like it could have been solved with a simple diamond or trumpet interchange to the airport road, and some frontage roads to cover up loose ends.
|
|
#
?
Oct 4, 2013 18:51
|
|
|
Well, we do have these everywhere, or more basic forms of it, but it looks like they overdid it a bit in your case! Or maybe they just haven't placed the new signs yet... The ones we have seem to work well, a roundabout helps to slow drivers down and make them realize it's not a highway any more, and you rarely need to wait. Entropist fucked around with this message at 20:10 on Oct 4, 2013 |
|
#
?
Oct 4, 2013 20:07
|
|
|
Baronjutter posted:http://goo.gl/maps/7avbJ It *looks* like there's nothing massively wrong with it. Install Windows posted:It really looks like it could have been solved with a simple diamond or trumpet interchange to the airport road, and some frontage roads to cover up loose ends. But it's just a diamond interchange anyway, and the roundabouts have only four legs each. Maybe there's something wrong with it on a micro level  e2: Okay I should have read the article haha Koesj fucked around with this message at 22:08 on Oct 4, 2013 |
|
#
?
Oct 4, 2013 22:03
|
|
|
Baronjutter posted:http://goo.gl/maps/7avbJ
|
|
#
?
Oct 4, 2013 22:14
|
|
|
Christ grover you don't go through roundabouts 'at speed', or are you going to go off into "but I was only doing 90 in a 55!" in this thread as well.
|
|
#
?
Oct 4, 2013 22:40
|
|
|
Koesj posted:Christ grover you don't go through roundabouts 'at speed', or are you going to go off into "but I was only doing 90 in a 55!" in this thread as well.  "at speed" being probably about 25-30mph in this case. If this was the first time I was doing this intersection, I'd probably be doing 10 under trying frantically to read the signs and figure out which way to go while simultaneously trying to avoid getting hit by an SUV.
grover fucked around with this message at 23:09 on Oct 4, 2013 |
|
#
?
Oct 4, 2013 23:05
|
|
|
grover posted:
This is 90% of the people using it. The other 5% are the locals that actually use it more than once every year while driving to the airport and getting pissed the gently caress off at idiots going slow and confused, and the other 5% are people driving "at speed" but having no loving clue what they're doing and do something insane like just turn left at the circle and try to drive straight towards the airport. I don't think on its own that it's a horrible design it's just: -The main road to the airport, so used by a lot of tourists and non-locals who all find it super confusing, at least the first times they use it. I know north Americans have to get better at this poo poo, but this roundabout is a bit of a "hard mode" level to throw people onto after a long flight. Poor visibility also makes it more confusing than it seems from the air. -The traffic volumes here in no way justify such a complex design and there's no development plans on even the farthest of horizons to warrant such over-building. -The whole thing was entirely political. This intersection was working just fine but a near by one is jammed to gently caress. But this intersection was in a riding that the ruling party won while the other intersection is in the riding of an opposition party. Baronjutter fucked around with this message at 23:23 on Oct 4, 2013 |
|
#
?
Oct 4, 2013 23:19
|
|
|
Mythbusters did a segment comparing the flow of a four way stop versus a roundabout configuration. No surprise here, the roundabout wins. https://www.youtube.com/watch?v=OvoFjirrgYA
|
|
#
?
Oct 5, 2013 16:24
|
|
|
Apparently, Pittsburgh is planning on rerouting bus lines away from the Golden Triangle. This definitely seems like an unwise decision on the city's part, since it would make their downtown much more difficult to get to via public transportation, but there are probably other reasons that escape me at the moment.
|
|
#
?
Oct 5, 2013 18:51
|
|
|
Hedera Helix posted:Apparently, Pittsburgh is planning on rerouting bus lines away from the Golden Triangle. This definitely seems like an unwise decision on the city's part, since it would make their downtown much more difficult to get to via public transportation, but there are probably other reasons that escape me at the moment. It sounds like the bus lines are awkwardly routed, with the main turnaround being inefficient. So it's possible that this could be a net positive. But trying to fix congestion by discouraging public transportation usage seems like a pretty bad idea. And the business owners seem a lot more interested in driving away "those people at the bus stations" than anything else.
|
|
#
?
Oct 5, 2013 18:59
|
|
|
Speaking of discouraging public transportation, Calcutta (India) recently banned biking on major roads in the name of speeding up traffic.
|
|
#
?
Oct 5, 2013 20:21
|
|
|
mamosodiumku posted:Speaking of discouraging public transportation, Calcutta (India) recently banned biking on major roads in the name of speeding up traffic. Oh, nice! It's a good thing that cars take up much less space than bicycles, and are specifically designed for the city's narrow streets. Otherwise, these new laws would be totally counterproductive in their stated goal of reducing traffic congestion.  Hopefully the movement against these laws is successful.
|
|
#
?
Oct 6, 2013 01:02
|
|
|
When a freeway-freeway intersection still has traffic lights, and it's been ready to be converted into a cloverleaf for These pictures say enough, I think. Carbon dioxide fucked around with this message at 21:31 on Oct 9, 2013 |
|
#
?
Oct 9, 2013 21:26
|
|
|
Don't fret, with the new A27 project coming up I'm sure they'll find a way to 
|
|
#
?
Oct 9, 2013 21:40
|
|
|
Carbon dioxide posted:When a freeway-freeway intersection still has traffic lights, and it's been ready to be converted into a cloverleaf for The bigger problem seems to be truckers not paying attention to the road because they are tired or distracted. There are a lot of them driving around in the Netherlands and you often see them driving halfway on the emergency lane. This was probably what killed a road worker two days ago along the A58 (a colleague, although I didn't know him). He had stopped in the emergency lane, presumably for maintenance or inspection, when a truck hit him from behind. We have accidents happen occasionally (a while ago at a subcontractor someone was injured after he drove off the first floor of a new building with a forklift) but I don't recall any other fatalities in the couple of years that I've worked here.
|
|
#
?
Oct 9, 2013 23:22
|
|
|
Koesj posted:Don't fret, with the new A27 project coming up I'm sure they'll find a way to What are you doing Netherlands, that is not how you make highway intersections 
|
|
#
?
Oct 10, 2013 00:04
|
|
|
Koesj posted:Don't fret, with the new A27 project coming up I'm sure they'll find a way to 35% Roadway Review Comments: Make the loop ramps look like testicles 65% Roadway Review Comments: No, one of mine hangs a LOT lower than the other one. 90% Roadway Review Comments: Perfect!
|
|
#
?
Oct 10, 2013 00:50
|
|
|
We woudn't want to do this: Noooo that would be stupid. Oh well it's in Brabant so what do I care.
|
|
#
?
Oct 10, 2013 02:02
|
|
|
Koesj posted:Don't fret, with the new A27 project coming up I'm sure they'll find a way to That's, uh, interesting. Honestly, it'd probably be cheaper (long-term) and use less space to just shove a stack in there. Devor posted:35% Roadway Review Comments: Make the loop ramps look like testicles Wow, I didn't even notice that. You could probably design an interchange that's a near-perfect copy of the Mona Lisa and I'd just stare at it, trying to figure out what kind of hosed-up local topography is forcing the ramps into such a weird configuration. Koesj posted:We woudn't want to do this: Pfft! Why bother with something logical, safe, and efficient when you can save money in the short term?
|
|
#
?
Oct 10, 2013 12:13
|
|
|
What's unsafe about those designs?
|
|
#
?
Oct 10, 2013 15:53
|
|
|
Baronjutter posted:What's unsafe about those designs?
|
|
#
?
Oct 10, 2013 18:23
|
|
|
GWBBQ posted:Cloverleaf intersections cause weaving, which is among the more dangerous things you can be forced to do while driving. Yeah, with the weaving they cause, you could say danger is looming in them! 
|
|
#
?
Oct 10, 2013 18:34
|
|
|
nielsm posted:Yeah, with the weaving they cause, you could say danger is looming in them!
|
|
#
?
Oct 10, 2013 18:53
|
|
God I fucking love Diablo 3 gold, it even paid for this shitty title
|
The first, economized design I posted has all the attractiveness of skimping on construction costs while keeping the existing safety and capacity issues well alive. The road authority knows this, or at least the engineering firm to whom they contracted this design does, but finance has been tightened quite a bit for medium term projects. Contrary to what Cichlidae said (I think he was being somewhat facetious), a stack interchange would be way more expensive, especially over the longer term. The trade-off that was made here is based on picking the most economically advantageous design for a ceiling price, with added incentives for a couple of design features (reusing existing bridges, keeping land acquisition costs low, minimizing capacity constraints during construction).  Land acquisition isn't that much of a problem here AFAIK, the dotted lines in the above pic are drainage ditches that probably delineate the original right-of-way reserved for the A27 (N-S) in the early 1960s. Now the proposed design exceeds those limits in the SW and SE corners but that land is not flagged for any development so they can easily buy it off of the owner for a government-set (fair market) price or expropriate it (for the same fair market price) if the owner is stalling. As an aside, when the N59 mainline was doubled and reflagged as the A59 in the late 80s, they simply kept the existing junction running instead of rebuilding it as planned for, again, cost reasons. Those were the bad old days of road construction here in the Netherlands. Koesj fucked around with this message at 22:58 on Oct 10, 2013 |
|
#
?
Oct 10, 2013 19:04
|
|
|
GWBBQ posted:Cloverleaf intersections cause weaving, which is among the more dangerous things you can be forced to do while driving. So the too-short sections where a single lane is both the acceleration lane for people merging in, and the lane for people leaving? There's a span like that where I live and I hate it because idiots who are turning off the highway just HAVE to get in their lane asap and everyone merging onto the highway just have to get on ASAP even though it's quite a long stretch so it's just a mess of cars of fairly different speeds zooming on and off the highway. http://goo.gl/maps/j6Qfu IS this a bad design? I see a LOT of weaving and lovely driving between these two ramps.
|
|
#
?
Oct 10, 2013 19:08
|
|
|
Question: Lifting a bundle of ~40ft rebar sections over live traffic probably violates some kind of health and safety regulations, does it not? I'm not a rigger, but I've been around enough of them to know you never go under a load, but this one was out over three lanes of cars. It was cool to see, but only because it was over the opposite lanes. 
|
|
#
?
Oct 10, 2013 21:11
|
|
|
MrYenko posted:Question: Lifting a bundle of ~40ft rebar sections over live traffic probably violates some kind of health and safety regulations, does it not? I'm not a rigger, but I've been around enough of them to know you never go under a load, but this one was out over three lanes of cars. That sounds like something you'd see at the start of a disastrous Russian dash cam video, not somewhere with first world safety regulations.
|
|
#
?
Oct 10, 2013 21:42
|
|
|
Baronjutter posted:http://goo.gl/maps/j6Qfu Well, let's have a little talk about weaving. If you have any merge followed by a diverge, you're going to have weaving. Since we can't space our ramps infinitely far apart, they're something we deal with everywhere. The real issue is how bad the weave is. The Highway Capacity Manual talks all about how to calculate weaving level of service, but it has its limitations. My most recent VISSIM simulation covers a situation with two such limitations! 1) What happens when you have nested weaving areas? 2) What happens when the weave distance is too long to analyze? Take a look at the location. We're looking at the eastbound direction. 2 lanes of CT 15 add on to the left side of I-84, followed shortly after by an on-ramp from Roberts Ave on the right. Another mile or so downstream, the left three lanes stay on I-84 and the right two go to I-384. Toss in the left exit to the HOV lane, and you've got a pretty bizarre situation. East Hartford wants to make it even more bizarre by adding an off-ramp from the right side of I-84 EB to Forbes Street, ostensibly to attract development to a nearby commercial site. Ignoring other reasons this might be a good or bad idea, when you look at it from an operational point of view... well, the on-ramp from Roberts will be extended as an auxiliary lane to the new off-ramp, so you're not technically reducing capacity, right? Let's have a look at what my analysis uncovered.  (Man, I love making these diagrams!) There's some interaction between the weaving areas here that the HCM methods wouldn't pick up. The critical bottleneck doesn't occur before the new off-ramp, but after it, which might seem paradoxical! Essentially, though, you can think of it as two competing weaving areas. With all those people changing lanes to get to the new off-ramp, cars that would have changed lanes earlier now have to wait until the 84/384 split is almost upon them to shift over. It's not a monumental change, but it's perceptible, to be sure: a 12mph average reduction in speed. MrYenko posted:Question: Lifting a bundle of ~40ft rebar sections over live traffic probably violates some kind of health and safety regulations, does it not? I'm not a rigger, but I've been around enough of them to know you never go under a load, but this one was out over three lanes of cars. Yeah, no, we don't do that. If OSHA found out, they'd... well, they wouldn't do anything, because they're on indefinite furlough, so that might explain the situation.
|
|
#
?
Oct 10, 2013 22:18
|
|
|
Baronjutter posted:That sounds like something you'd see at the start of a disastrous Russian dash cam video, not somewhere with first world safety regulations. Miami, so the first idea is probably more accurate than the second.
|
|
#
?
Oct 10, 2013 23:03
|
|
|
Is there a rule for the distance from the exit those fat markings (elephant tracks?) should start being placed when a lane becomes an exit only lane?
|
|
#
?
Oct 11, 2013 02:26
|
|
|
mamosodiumku posted:Is there a rule for the distance from the exit those fat markings (elephant tracks?) should start being placed when a lane becomes an exit only lane? 1/2 mile if it's an isolated lane drop, up to 2 miles if it's an auxiliary lane.
|
|
#
?
Oct 11, 2013 02:37
|
|
|
MrYenko posted:Miami, so the first idea is probably more accurate than the second. The 826/836 shitfest of construction? One of the many reasons I rarely leave the Grove.
|
|
#
?
Oct 11, 2013 04:17
|
|
|
I've been reading this thread for the past several months (it's been fascinating!), and I've got two questions. I was driving through Maryland several weeks ago on MD 5/235 and saw several of these strange intersections: http://goo.gl/maps/fM7r8 What is this intersection called and why would it be made this way, instead of making a 3-way stop with traffic signals? I did find another one of the same sort but with stop signs instead: http://goo.gl/maps/hLqv2
|
|
#
?
Oct 11, 2013 12:20
|
|
|
Alakantar posted:I've been reading this thread for the past several months (it's been fascinating!), and I've got two questions. I was driving through Maryland several weeks ago on MD 5/235 and saw several of these strange intersections: http://goo.gl/maps/fM7r8 It's called a Seagull in Australia where it is most popular.
|
|
#
?
Oct 11, 2013 12:41
|
|
|
|
| # ? Apr 28, 2024 06:17 |
|
|
Alakantar posted:I've been reading this thread for the past several months (it's been fascinating!), and I've got two questions. I was driving through Maryland several weeks ago on MD 5/235 and saw several of these strange intersections: http://goo.gl/maps/fM7r8 Three Notch Road seems to be larger/more important. If that was in Europe, Point Lookout Road would probably have had a yield sign towards Three Notch Road, and Three Notch Road no controlling signs apart from notices that there is a side road. The turn lanes would have been removed, except for turning southwards coming from east (left turn from the larger road.) It lets the traffic on the larger road glide instead of forcing everyone to stop because of a side road that might not receive a tenth the traffic. (I'm basing this guess on the number of lanes on each road.) nielsm fucked around with this message at 12:55 on Oct 11, 2013 |
|
#
?
Oct 11, 2013 12:52
|
|