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Blanket 80km/h Speed Limits Around Melbourne?

Discussion in 'General Motorcycling Discussion' at netrider.net.au started by mjt57, Jun 12, 2008.

  1. I was listening to 3AW before. They were talking about reduced speed limits on the freeways (and tollways). Vicroads is claiming that reduced limits reduce crashes as well as improving overall throughput (traffic flow).

    Now, I only occasionally visit Melbourne, but when I do, if it's peak hour or getting close to peak hour the traffic flow is typically less than 80 klicks despite whatever speed limit is imposed at the time.

    I am trying to understand why a lower speed limit will improve traffic flow? Surely if you have say, a million cars that if they are travelling slower to get on, along and off the Monash (or whatever road), then the throughput will be lower?

    Those of you who ride these roads commuting could probably explain this better. But I would have thought that the higher the limit the quicker that the traffic gets on and off the freeways and to their destinations.

    I would hate it if I had to do 80 klicks all the way from Narre-Warren to the City. I tend to time my trips so it's during the low traffic periods. So it would be doubly annoying that if I'm on a 3/4 lane freeway and there's little traffic and I'm stuck at 80 klicks.

    Of course, the cynic in me makes me wonder if it's not another ploy to "entrap" people into speeding and hence setting up speed traps to nab 'em.

    Thoughts, anyone?
  2. Lower limits won't solve anything.
    Actually enforcing the "keep left" law and therefore reducing the number of vehicles weaving between lanes trying to get past slow moving traffic would be a good start though - it's the reason why the Autobahns work so well.
  3. :shock: OMFG... they'll never learn, Australia is big, we need to travel at a set rate to get somewhere, we can travel across Victoria for 10 hours and still be inside the state, in Europe you'd have crossed 3 countries by then...

    As you pointed out, less speed means less throughput in NON-Peak hour times, and Peak hour is stuffed anyway, cos Citylink cant keep their promise of "Sooner, Safer", its just another road, that people have to pay to use. I use the Eastern everyday, its a dream compared to the Monash, and its free... (And the Eastlink I wont be using as my place is quicker to get to by jumping off at Springy anyway).

    And the stupid "wave" traffic effect of brake, accelerate, brake, etc, still shits me, ESP. as you reach like Stud Road and then you can plant your foot all you like as there is no more traffic in sight :roll:
  4. +1M...
    I was on the Monash the other day and a slow moving truck decided the smaller truck in the middle lane wasn't going fast enough for him, so he moved into the right lane, "NOoooooo".... trucks should not be allowed to use the right hand lane, there are 2 perfectly other good lanes for them to be slow in. And yes, the keeping left of the right hand lane for all vehicles going slower than the person behind you would be great...
  5. The other problem is that when you have cars in the right lane "blocked" by slow vehicles they usually try and get past by diving into tiny gaps in the left lane. This causes the vehicle they've just cut in front of to brake, which slows down all cars behind them, which encourages more people to move into the right hand lane and block it. From what I've seen it seems to be a major cause of the stop-start nature of the Monash (that and the f-wits in the RH lane that wait till the last minute to move left so they can exit).

    The German system of issuing hefty penalties (something like a month or so loss of licence I believe) for failing to keep left (or in their case keep right), as well as similar penalties for undertaking, would work well here for stopping a lot of the dumb shit drivers do - particularly it seems on the Monash.
  6. I was going to suggest that none of it would matter one day - that they'd have sensors in the roads and automate all cars and remove all driver controls apart from the ability to input a destination and have the vehicle drive you there...but then I realised the error of my thinking. The government would never allow it as it would mean a massive loss of revenue from their "safety" cameras.

    The ideal solution is of course to drop all speed limits on freeways/tollways/highways. Why stop at 80? Let's make it 60! And make sure that it isn't something slightly sensible like only applicable to peak hour, but make the limit applicable 24 hours a day! So that you can be driving at 1am on an empty road and crawl along like a 90 year old in a Datsun 120Y!
  7. Some European cities use this but they have it setup as a variable speed limit. So between 7 - 10 in the morning they will set the limit to something like 70km/h the idea being that once the density of traffic increases people will keep the same following distance no matter what speed they are doing. And it only takes a few people to tap there brakes too hard to setup a standing wave in this sort of traffic. So if you think of the traffic as a big spring there are two ways to reduce the propegation of waves through this spring. One is to reduce the tension in it (ie everyone keeps moving faster but leaves a decent following distance) or if everyone is gonna run up each others arse (then you need to decrease the speed to force them to keep a decent following distance).

    You might have noticed sometimes traffic will slow down and speed up for pretty much no reason whatsoever. This is due to the standing waves that are setup by people not leaving proper following distances which ends up slowing down traffic further behind them. Though overseas they have it setup as a variable speed limit so after peak hour periods the road will go back to being a 100 road. So to sum it up you basically get more throughput becuase traffic should theoretically drive more smoothly (rather than this slow to 40 speed up to 90, slow to 40 speed up to 90 etc etc). Though i doubt it would make the road much safer, it might help to slightly speed up congestion, (i suppose it might slightly reduce the number of rear end accident's but i doubt by much....).
  8. I don't mind the idea, actually.

    The sooner the government completely takes away my responsibility to drive to the conditions, the sooner I can catch up on my sleep while driving.

    Think of just how much more relaxing driving will be, when you don't have to pay attention to the road!
  9. Or basically "if you can't prevent crashes from occurring, then just reduce the speed at which they occur" - rather than addressing the real cause which is the fact most people out there don't know how to drive.
  10. So, can anyone tell me who was saying what on AW? Is this a Vicroads initiative, or are they responding to someone else's brainwave?
  11. +1 yes, the idea behind it is that a continuous stream of traffic travelling at 80K/H allows much more throughput than 110 - 0 - 110 - 0 etc. I've seen a computer model of it actually.

    And also I'm from NSW and I always get frustrated that there are better roads down heer and the speed limit is lower?!?!
  13. Which just goes to show why the blind obsession with speeding is so stupid. Why is a few cars doing 5-10kph over the limit such a problem if you have thousands failing to maintain a safe distance (in addition to all those breaking the "keep left" law).
    Again it all just comes down to inadequate driver training/education and a lazy, simplified approach to enforcing safety by not eliminating the cause of crashes, just attempting to reduce their severity.

    As for the congestion issue I think that has more to do with poor road planning - like sticking traffic lights at the end of exit ramps causing traffic to back up onto the highway, and placing exits/entries too close together resulting in a mad shuffle as cars that have just entered try to move to the right at the same time as cars already in the RH lane try to move left to exit.
  14. I'd be interested to see. I sometimes wonder if traffic travelling at 100KMph towards an 80KMph zone isn't like those movies where you see space ships coming out of warp.

    For example the traffic coming from the western burbs inbound on the Westgate freeway at 100KMph have to slow to 80KMph once they reach the bridge. So naturally the traffic is going to bank-up.

    I don't know the science or solution but I am willing to see if it would help.
  15. Thats actually why it reduces congestion, because it is easier to change lanes and has less affect on the traffic flow when the speed is slower during medium/heavy traffic which means it is easier to merge on and off the freeway. I am not saying they should reduce the speed limit, i think half the speed limits on the ring roads in sydney are too slow and should all be 80 instead of 60. Still doesn't change the fact it has been shown that certain speed limits can reduce congestion in Medium/Heavy Traffic.
  16. Put in variable speed limit signs on the main areas, and trial it for a month. If it doesn't work change back. I understand they are trying to stop the 'hard accelerate, hard brake' drivers which cause problems with the 'traffic wave' and actually slow everyone down. Best thing imo to keep traffic flowing properly is to ensure people keep proper distances, and slow down in advance rather than stop quickly where the traffic is stopped - as that way traffic slows rather than stops, and stopping = wasted time.

    Fark the cagers, bring in motorcycle lanes on the freeway and give us 130kmh minimum speed limit.
  17. Yeah I've seen the mathematical models supporting theories like that, but I dunno - I'm still not convinced it works in reality. If anything I reckon lower speed limits just encourages people to pay even less attention and do even dumber things.
    Problem is though that if the Government does introduce 80kph limits, and the road toll doesn't change (or even goes up), we'll still be stuck with 80kph limits. With the added bonus that anyone still driving/riding at the previously considered "safe" speed of 100kph risks losing their licence - even if it's at 6am on a Sunday morning and they virtually have the entire road to themselves. In fact they'd probably use them as an example of why "speed" is still responsible for the high road toll - and use that as an excuse to lower the speed limits even further. And of course if the speed limit is lowered enough then all of a sudden the roads don't seem as congested - since an average speed of 20kph looks a lot better in a 60kph zone than a 100kph one.
  18. there wouldn't be a problem with people merging onto freeways, if most people reached the surrounding speed before trying to merge. as most people are afraid of getting up to speed when they are entering a freeway, then accidents are more likely to happen

    hence the reduce speed between westgate bridge and the tunnel
    the tunnel is also 80 as they have no emergency lanes.

    once you leave the tunnel to go to the eastern suburbs, its still 80 cause they have narrowed the lanes, removed the emergency lanes, and left grooves in the middle of the road (loves grabbing motorbike wheels)

    on the exits to the eastern suburbs, they have also reduce the size / length of the exit lane, which jams up traffic more...

    This is all because they are "making another lane" on the monash so it should flow a little better.

    Most mornings I find I usually travel at around 40-60 (not trying to filter / split). In the evenings, its usually 60-80 til my turn-off... after that it usually a crawl.

    And it also goes to a crawl, cause some idiot has decided that even though the intersection is blocked they will still go through it, blocking it for everyone else.
  19. This all came about because they're dropping the limit down on the Calder in the Keilor Valley to 80km/h.

    They've turned the emergency lane into a third running lane and it seems to be working but it's now a pain in non peak periods having to run at 80.