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Koesj posted:Whoa strange stuff going on with all those contracter issues, are these all done cost-plus or something? Really sounds like how things got done here in the Netherlands 30 years ago. These days every semi complicated job is molded in some kind of PPP agreement where there's alliances of engineering firms, general contractors and specialized guys bidding on all kinds of incentivized cost, performance and quality targets. Some of it (design-build) is no-bid, so whoever has the best ties with politicians gets that contract and spends as much as they please. The majority, though, is bid, and we're obliged to choose the low bid unless something looks extremely shady. The Busway is another great example of corruption: propose a project for you to design and your buddies to build, get it approved, then gradually ramp up the cost, all the while skimming cash off the top for design changes. The work I did in France was with a PPP, and that worked out a lot better. The company was a concessionary for 65 years, so they had a big incentive to get things working ASAP, as they were wasting their own money every day it wasn't done.
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Sep 18, 2012 22:12
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Cichlidae posted:The work I did in France was with a PPP, and that worked out a lot better. The company was a concessionary for 65 years, so they had a big incentive to get things working ASAP, as they were wasting their own money every day it wasn't done. That's pretty much our DBFOI model. We operate the site for the financing period (35-50 years) so it's in our interest to keep up front, maintenance, and long-term costs low, while keeping pavement condition high.
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Sep 18, 2012 22:35
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Chaos Motor posted:DBFOI huh
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Sep 18, 2012 22:38
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Cichlidae posted:Some of it (design-build) is no-bid, so whoever has the best ties with politicians gets that contract and spends as much as they please. The majority, though, is bid, and we're obliged to choose the low bid unless something looks extremely shady.
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Sep 18, 2012 23:33
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grover posted:What kind of screwed up contract is that? Every design-build contract I've ever had done was still bid on, it just included the engineering and construction all in one bid package. I know there's a good way to do it (we do that with some bridges, and it turns out fine), but it also opens itself up to a ridiculous amount of corruption if it's not bid. Past Governors have exercised their power to force the DOT into unwise positions. I'd be amazed if there's a foolproof system out there; the closest I've seen is concessionary arrangements, or incentives for early completion / meeting goals, but we don't do either of those here in CT, unless you count the service plazas, which are a concessionary agreement. Edit: Ideally, I'd like a system where the contractor gets a fraction of the user benefit resulting from the project. Build an interchange that saves the public $1B/year over the existing interchange? You'll get something like $20M/year as long as it's still standing. Unfortunately, contractors will probably want the money up front, and that's a big barrier to start-ups. You would also need an extremely solid way of calculating user costs and benefits. Cichlidae fucked around with this message at 23:55 on Sep 18, 2012 |
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Sep 18, 2012 23:46
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Mandalay posted:huh Design - Build - Finance - Operate. The extra part we add is Insure.
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Sep 19, 2012 04:58
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Chaos Motor posted:Design - Build - Finance - Operate. The extra part we add is Insure. One issue we've come across: how do you provide a long-term guarantee that your company will be available to cover the "insure" part in 5, 10, 20, 50 years? How does your contract get around that?
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Sep 19, 2012 12:23
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That's a great question! It's the same problem with any insurance company, especially a new one. How do you know that WeSellInsurance is going to exist when you finally die, to pay the account? If WeSellInsurance hasn't been around as long as you expect to continue living, what surety do you have? Well, here's what we do - we assume that the city, the financier, or IR will exist, and if any party continues to exist, the policy continues to exist. While IR is high risk, the financier may be moderate risk, the likelihood of the city ceasing to exist is VERY low. We set up an SPV - "Special Purpose Vehicle". The financier capitalizes the SPV with the cash needed to perform the work. IR spends that cash on completing the job site. The owner repays that cash over the financing term by recapitalizing the SPV, including interest, insurance, and management expenses - all of this together is still cheaper over the financing period than buying asphalt and paying cash to maintain it. The financier receives finance payments from the SPV to repay the initial capitalization plus interest, and the remaining cash is spent on insurance & management. The insurance account is actually cash-accrual, so it starts out empty (you don't expect any problems in the first few years anyway), and builds over time (the more time that goes by, the more expensive the fix will generally be). The policy is re-insured (all insurance policies are re-insured), in case there is an early problem, prior to the policy capitalizing. The cash value of the insurance is reinvested in some stable entity, which can be complicated by investing in the REIT, or simple with a bank CD or similar. Regardless, the funds are contractually bound for this job site only so there's no shenanigans by anyone. If IR goes defunct, the SPV still exists, the remaining members divide the assets appropriately, and the cash value of the policy still exists in its entirety in its own account, firewalled from any other specific investment. The SPV continues to pay into the insurance account, like self-insurance for a fleet owner, and can appropriate those funds for service as per the insurance contract. If all goes well over the financing period, all three parties split the cash value of the insurance at the end of financing (with the expectation that the owner will re-invest their cash portion into new IR infrastructure purchases), as an incentive to all parties to minimize use of insurance and maximize initial quality. If the street has had problems, the insurance policy may be cash negative, so there's no payout. If IR has gone out of business, the account shifts to the owner, who gets the entire policy, and it's their issue - but it was their issue originally, and now they've got cash that can only be spent on this job site. Basically, the way we've got it set up, if IR goes kaput, nothing changes, because both the city and the financier continue to exist to service and maintain the accounts.
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Sep 19, 2012 15:18
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That sounds a lot cooler than I expected it to. Is there a decent magazine and/or book on this topic suitable for beginners who have maybe taken a microecon class or two many years ago?
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Sep 19, 2012 18:04
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Not that I know of, I've pretty much had to put this together myself over the last couple years by talking to PubWorks, financiers, and insurance companies. Even then they have trouble wrapping their heads around it because what insurer gives you direct access to the policy's value? These guys sit on billions of dollars worth of uninsured assets and they don't seem to get that their ongoing costs could be greatly reduced if there was some kind of performance surety that has the designer and builder invested in the long term health, outside of cash bonding which really ruins small companies and greatly limits growth of large ones. So, I've made it my business to put this together to support sales of our products. Do note that we haven't actually written one of these policies yet.
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Sep 19, 2012 18:45
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Chaos Motor posted:Contract stuff I'm not sure I understand it 100%; the financier pays for the initial cost, and then the city dumps in a regular fee over time? Who is the financier, exactly? ----- Today's a special day: we engineers get to propose legislation we'd like to see enacted. It's like a Christmas wish list, except your parents spend all their disposable income on lottery tickets, so chances are you won't get anything. I asked for two things: - That speed limits on freeways be statutorily related to the 85th percentile speed, and - That our drunk driving penalties match the Federal requirements so we don't keep losing our funding.
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Sep 19, 2012 23:07
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Cichlidae posted:I'm not sure I understand it 100%; the financier pays for the initial cost, and then the city dumps in a regular fee over time? Who is the financier, exactly?
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Sep 20, 2012 03:00
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grover posted:How is the 85th percentile calculated? Wouldn't it differ greatly depending on what the posted limit was when the study was conducted? Cover the signs, measure the speed in the middle of a straight, noncongested stretch during off-peak hours. Measure again every 3 years or so. Ya know, in accordance with the MUTCD: BIBLE posted:Standard: Note that it doesn't say "Maybe" or "Perhaps" or even "Should." It's right there: "SHALL." We ignore a SHALL, and that's grounds for a ton of lawsuits and loss of Federal funding. We track 85th %ile speeds on every road EXCEPT freeways, and periodically re-check them on every road EXCEPT freeways, probably because someone in the past decided that it's easier to ignore the MUTCD this way. They're wrong, though; even if we take the speeds and just throw them out the window and stick with what's out there now, it's more defensible than not even sampling the speeds. Edit: Hell, if anyone got a speeding ticket just about anywhere in Connecticut, provided they weren't going far over the 85th, they could probably get away with it on the grounds that (as far as I know) the vast majority of speed limits in the state are fiat. Cichlidae fucked around with this message at 03:23 on Sep 20, 2012 |
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Sep 20, 2012 03:06
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Cichlidae posted:I'm not sure I understand it 100%; the financier pays for the initial cost, and then the city dumps in a regular fee over time? Who is the financier, exactly? That's pretty much it. Think about it like taking a home construction mortgage from a bank. The bank pays for your house to be built, and you pay them back over time through the mortgage. The financier would be whoever is putting up the cash, ideally a Real Estate Investment Trust, because their expected returns and investment profile fit very well with the terms and rates that a city would need in this model, and REIT investments were originally, as I understand it, an attempt to bring a more flexible bonding model to private developments. As it so happens, now they have the opportunity to provide a flexible bonding alternative right in the heart of bond country, with municipal public works financing. "Because of their access to corporate-level debt and equity that typical real estate owners cannot access, REITs have a favorable capital structure. They are able to use this capital to finance tenant improvement costs and leasing commissions that less capitalized owners cannot afford."
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Sep 20, 2012 05:09
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Cichlidae posted:Cover the signs, measure the speed in the middle of a straight, noncongested stretch during off-peak hours. Measure again every 3 years or so. Ya know, in accordance with the MUTCD: How important is the 'cover the signs' part? They never do that here and in certain areas with ridiculously low speed limits run extremely visible traffic enforcement.
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Sep 20, 2012 05:22
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dexter posted:How important is the 'cover the signs' part? They never do that here and in certain areas with ridiculously low speed limits run extremely visible traffic enforcement. Even with the signs covered, I'm not sure if it would be accurate. I don't know about the rest of you, but my comfort zone is so far above most posted speed limits that my speed is entirely dependant on what's posted. If I don't know what the speed limit is, I usually drive slower just to make sure I'm not accidentally going 20+ over the limit. Are there signs that say "speed survey in progress, drive whatever speed you're comfortable"?
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Sep 20, 2012 11:31
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dexter posted:How important is the 'cover the signs' part? They never do that here and in certain areas with ridiculously low speed limits run extremely visible traffic enforcement. It's vital to collecting accurate speed data, though often ignored. Even if the 85th is artificially low, though, they should be running the survey again periodically, so eventually the speeds will level off at an accurate value. grover posted:Even with the signs covered, I'm not sure if it would be accurate. I don't know about the rest of you, but my comfort zone is so far above most posted speed limits that my speed is entirely dependant on what's posted. If I don't know what the speed limit is, I usually drive slower just to make sure I'm not accidentally going 20+ over the limit. There is not such a sign, at least not in the MUTCD. I think that might have the opposite effect on drivers, and they might drive faster than they're comfortable doing, much like they do with the electronic "YOUR SPEED" signs. It's probably best to follow an incremental approach and re-sample every year or two.
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Sep 20, 2012 12:24
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Cichlidae posted:Edit: Hell, if anyone got a speeding ticket just about anywhere in Connecticut, provided they weren't going far over the 85th, they could probably get away with it on the grounds that (as far as I know) the vast majority of speed limits in the state are fiat.  Your honor, the speed limit of 25mph clearly has no relation to the 85th percentile that the DOT already measured of 45mph. I don't give a gently caress. You now owe the original ticket plus $100 in court fees.
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Sep 20, 2012 13:38
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Cichlidae posted:It's vital to collecting accurate speed data, though often ignored. Even if the 85th is artificially low, though, they should be running the survey again periodically, so eventually the speeds will level off at an accurate value. I lived in a place for about six years on and off that had no posted speed limit on well maintained rural roads. I found that the speed drove at was highly dependent on road conditions. A nice sunny day during the dry season on a gun barrel straight section of road? 160-180kmh in my work v6, 190-210kmh in my personal v8. Regular road during the wet season? About 160 would be the max I was comfortable with. About eight or so years ago they did a 85th percentile on the rural roads and dropped the limit to a maximum 130kph, though there is a shady agreement that the territory police won't bust you for less than 160 unless you are doing something pretty dumb, or are on their shitlist as an arsehole. The trouble is, that not everyone drives an A4 with AWD, curtain airbags, and good handling characteristics at high speed. Some people, especially young and inexperienced drivers (who are also the most likely to make a poor judgement call and drive impaired due to drugs or alcohol), drive really lovely old cars. That 85th percentile really can chafe your nuts, but it has to take into account a whole load of variables.
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Sep 20, 2012 14:13
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T.Worth posted:I lived in a place for about six years on and off that had no posted speed limit on well maintained rural roads. I found that the speed drove at was highly dependent on road conditions. A nice sunny day during the dry season on a gun barrel straight section of road? 160-180kmh in my work v6, 190-210kmh in my personal v8. Regular road during the wet season? About 160 would be the max I was comfortable with. Now you have to tell us where this was. At least which country.
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Sep 20, 2012 15:01
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Hippie Hedgehog posted:Now you have to tell us where this was. At least which country. Northern Territory in Australia. Local paper used to run front page pictures of BMW, Lamborghini, Mercedes, Ferrari, Audi, Jaguar, Bentley and Aston Martin hot weather testing cars on the roads there with an inset of the reading the hand held laser got as they shot past. Thoroughly ridiculous speeds were reached, then they turned around and went back. E: Pretty sure I woke up one Saturday grabbed the paper and the local rag had clocked an M3 doing 314kmh... In convoy... With another M3. They had weird checked paint jobs over the front and back so you couldn't figure out the lines of the yet to be released car. T.Worth fucked around with this message at 15:24 on Sep 20, 2012 |
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Sep 20, 2012 15:15
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Volmarias posted:
It's all about how you present it. Gotta think like a lawyer. READER PARTICIPATION TIME Remember how I asked you to design the logo for Traffic Engineering last year? Sure, the bosses shot them down, but it was a hell of a lot of fun (and I still have one hanging on my wall). Well, I'm designing a handbook filled with traffic control plans for the Maintenance guys to use out in the field. It's a little laminated affair; we'll probably make 500 copies and give them to all the personnel to keep on hand. The previous version of the handbook had a typo in the title: "WORK ZONE TRAFFIC GUIDLINES." This has become something of an in-joke in the office, so if you're looking for some humor to work with, that's your spark of inspiration. The dimensions are 3.7 wide by 7" tall, so anything around that size should be fine. It's time to show off your graphic design skills! As always, I'll take the best couple and pitch them to my boss.  (a lovely example)
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Sep 20, 2012 23:00
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Cichlidae posted:It's all about how you present it. Gotta think like a lawyer. Gotta remember that that zone is a revenue generation device, not a measure for public safety. https://maps.google.com/maps?q=ceda...Jersey&t=h&z=19 Cedar Lane, Highland Park. 4 lane road, 25mph. Notorious speed trap. You'll notice that Livingston is right next door. Lets put it this way; the cops were pulling over multiple cars and having people pull over BEHIND them. The cop had the chutzpah to tell me about all of the little kids running around (it's entirely grad student housing, no kids). quote:GUIDLINES http://en.wikipedia.org/wiki/Globally_unique_identifier but I have no idea how you'd fit it in.
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Sep 20, 2012 23:10
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A question about the thinking behind something... My local municipality here in NC has, in places, been replacing your standard five-light straight-plus-left-turn lights with dedicated left-turn lights. These things, though, have four lights: the usual three, plus a flashing yellow arrow for unprotected left turn. The idea is that they can, while giving one direction green with protected left turn, give the opposite left turners an unprotected left while holding the straight traffic with a red. Theoretically I can see the benefit... maybe you can get a few extra cars through if there's nobody going straight, and more options for engineers is always a plus. But is the practical benefit all that great? They've mostly been placed in higher volume intersections where you MIGHT get a car or two through before it's unprotected left for everybody. But they've been in for about a year now and I've only noticed one lane where they reverted to a standard three-light left-turn. Any thoughts?
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Sep 21, 2012 21:48
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They put a bunch of those in here in KC, and left-turn throughput on those intersections is MUCH higher now.
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Sep 21, 2012 22:02
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dupersaurus posted:A question about the thinking behind something... I don't know where in NC you are, but here in Charlotte they just spent a small fortune installing those pretty much anywhere there is a dedicated left turn lane that is not a main arterial. It's great because in many places, a protected left is only necessary for two hours a day, but during those two hours it's really necessary to prevent congestion. On a side note, the traffic engineers in Charlotte are fantastic. After reading this thread, I have come to admire just how well they do their jobs.
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Sep 21, 2012 22:43
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dupersaurus posted:A question about the thinking behind something... I'm not sure I understand what you're saying. They had a five-section doghouse for protected-permissive lefts, and they replaced them with a four-section head that runs permissive only? But if it's permissive, why hold the opposing throughs? If you have the opposing left protected, you may as well run protected both ways. Can you draw a diagram or find a picture?
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Sep 22, 2012 03:32
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I think what he said was that a certain direction will have a permissive left turn indicated by a flashing yellow arrow. Straight-through traffic traveling through that intersection will be red. Opposite the intersection, straight through traffic is permitted and the left turn lane is protected. It sounds to me just like the system they use in Austin, only in Austin they use green balls on the left turn lane signal that are only visible in the immediate vicinity of the turn lane, and the 5-light unit is mounted over the turn lane. See this intersection. Many of the traffic lights in Austin go to flashing yellow/red at night anyway, which means one can blaze through the city at 4 am without ever being stuck at a light for no reason. edit: many blaze through the city at all hours of the day which fantastically explains the occasionally uber calm traffic grillster fucked around with this message at 05:12 on Sep 22, 2012 |
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Sep 22, 2012 04:52
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Why in the gently caress are they cutting tar snakes into all my highways right now
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Sep 22, 2012 07:33
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Cichlidae posted:I'm not sure I understand what you're saying. They had a five-section doghouse for protected-permissive lefts, and they replaced them with a four-section head that runs permissive only? But if it's permissive, why hold the opposing throughs? If you have the opposing left protected, you may as well run protected both ways. I think dupersaurus is describing this kind of light:  Wisconsin is starting to use these in a lot of places and WisDOT has a page up about them: http://www.dot.wisconsin.gov/travel/flashing-yellow.htm As far as I know, Wisconsin never uses doghouse lights anywhere. I've only ever seen straight-line five section signal heads or those for protected-permissive left turns. I think the situation dupersaurus is describing would be something like having a green ball and arrow in one direction and the opposing traffic having a red ball and a flashing yellow arrow.
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Sep 22, 2012 20:32
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They started switching to those lights for left turns out in Nevada as well. I was pissed for the first three weeks they were installed when the flashing yellow phase was totally disabled.
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Sep 22, 2012 21:30
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Dominus Vobiscum posted:I think dupersaurus is describing this kind of light: Yeah, that. Red, yellow, flashing yellow (unprotected), and green. Really the only functional difference from the five-light style is that if one direction has all-green, then they can (and do) give the opposing left turners the flashing yellow while holding the throughs at red. Coasterphreak posted:I don't know where in NC you are, but here in Charlotte they just spent a small fortune installing those pretty much anywhere there is a dedicated left turn lane that is not a main arterial. It's great because in many places, a protected left is only necessary for two hours a day, but during those two hours it's really necessary to prevent congestion. I'm in Cary, which is a suburb of Raleigh. Interestingly, though, Cary seems to be the only place in the area actually putting them in, but only really in a few of the heavier intersections on my side of town where sometimes the turning volume is greater than the through volume. It seems a little odd.
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Sep 22, 2012 21:54
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I imagine the flashing yellow arrow is also much safer than the green globe as far as making drivers aware that it is actually a yield.
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Sep 22, 2012 22:37
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Dominus Vobiscum posted:I think dupersaurus is describing this kind of light: Alright, so they get a permissive left whereas before they'd had a red arrow or red ball. Fair enough! Seems lots of states are putting in the flashing yellow since the new MUTCD allows it. Millstone posted:Why in the gently caress are they cutting tar snakes into all my highways right now Probably crack sealing. It's cheaper than resurfacing, and keeps the pavement intact for a while. ManicJason posted:I imagine the flashing yellow arrow is also much safer than the green globe as far as making drivers aware that it is actually a yield. Yes, it's certainly a lot more clear. A green ball and green arrow are hard to distinguish in many cases, so I'm all for making things as unambiguous as possible.
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Sep 22, 2012 22:52
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ManicJason posted:I imagine the flashing yellow arrow is also much safer than the green globe as far as making drivers aware that it is actually a yield. It is, they've done studies and drivers find it more intuitive so the flashing yellow arrow was added to the MUTCD this last go-around. We've used the permissive green ball for a long time in Texas but I gotta admit when I moved here from Georgia (in like '94), I didn't understand it at first. We're planning to switch over to the flashing yellow arrow soon but I don't know what the timeline is.
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Sep 23, 2012 02:26
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I was thinking about the subway map when I was reading this article that was submitted on hacker news. http://stamen.com/zero1/
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Sep 23, 2012 03:05
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crazysim posted:I was thinking about the subway map when I was reading this article that was submitted on hacker news. Man, that's exactly the kind of thing I'd be doing if I were an artist instead of an engineer. I love turning messes of data into something that can be easily understood. Heck, in France, I made a map of sounds and smells throughout a neighborhood as part of my Urbanisme class.
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Sep 23, 2012 04:30
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Cichlidae posted:
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Sep 23, 2012 17:11
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Millstone posted:They're creating the crack, then filling the crack. Billions of them. Some sort of anti-buckling measure? In straight lines, or snaking around? We make "expansion joints" in concrete, which are just glorified cracks, but they're in a straight line, so they concentrate stresses in the least damaging way. I can't imagine why anyone would make non-linear cracks.
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Sep 23, 2012 17:54
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grover posted:Even with the signs covered, I'm not sure if it would be accurate. I don't know about the rest of you, but my comfort zone is so far above most posted speed limits that my speed is entirely dependant on what's posted. If I don't know what the speed limit is, I usually drive slower just to make sure I'm not accidentally going 20+ over the limit. Agreed on the signs covered. Practically all of my driving/riding is on the same roads and I know the speed limits for each area without having to look for the most part. I can even tell when someone is going faster/slower by the feel of the car if it's one I'm familiar with. And then with the signs taped over, before the post about it, I'd assume that they were actually lower because of construction or something.
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Sep 23, 2012 18:34
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