Roads: Increase Ontario 400-series Highway Speed Limit

[cbrown2009]

I firmly believe the limit could and should go to 120. In clear to moderate traffic on any 400 series hwy, 120 is easily achievable. But I think in conjunction the authorities need to enforce the left lane a little better. Keep those slowpokes out of there. Actually, they could do a better job of that in any case. But an absolute necessity with a 120k/h limit

 

[nfitz]

That's surprising, I would of assumed that at least the express portion of the 401 was designed to support at least 120km,

It would have been designed for 80 mph (129 km/hr). The speed limit on 400-series highway used to be 70 mph (113 km/hr), before being dropped to 60 mph (97 km/hr) in the early 1970s.

These days MTO uses a 130 km/hr design speed on 400-series highways.

I firmly believe the limit could and should go to 120. In clear to moderate traffic on any 400 series hwy, 120 is easily achievable. But I think in conjunction the authorities need to enforce the left lane a little better. Keep those slowpokes out of there. Actually, they could do a better job of that in any case. But an absolute necessity with a 120k/h limit

You don't want people going faster than the 130 km/hr design speed. Which you would get more frequently with a speed limit of 120 km/hr. I can see possibly putting the speed limit back to 110 km/hr - but I can't see any higher.

 

[cbrown2009]

You don't want people going faster than the 130 km/hr design speed. Which you would get more frequently with a speed limit of 120 km/hr. I can see possibly putting the speed limit back to 110 km/hr - but I can't see any higher.

I see youyour point but I don't mind seeing a little more enforcement to govern that. Even now there are folks out there myself included on rare occasions where I can find myself clocking in the 130s if I'm not watching my speedometer. I could live with 110 within city limits & 120 through rural areas.

But while yes there are more drivers who would try to push the envelope that much further, most times of day 120-125 is about as fast as traffic would naturally allow anyways. And again with better enforcement, which I believe is needed anyways, establishing a 120 limit with a grace of 130 would be cool. IMHO

After all, in any other speed zone, if you're caught doing 10-20 km over the limit, you're getting that ticket. By contrast, even now at 120 on the 407, one pretty much can't be in the left lane

 

[nfitz]

I see youyour point but I don't mind seeing a little more enforcement to govern that.

That seems unrealistic. And is it an efficient use of police resources?

I'd think the current system works fairly well.

 

[Mulder]

That's surprising, I would of assumed that at least the express portion of the 401 was designed to support at least 120km, especially after recent improvements. So is it only good for 100? 110? Just never felt like that was the case when I was doing 150k on the express lanes, in light traffic of course, during my younger days(obviously not that reckless anymore)

Do you know what the restricting factor is? Are the ramps too short, or is it poor sightlines- vertical/horizontal, the grade, lane width, something else or a combination of factors?

Upgrading highways to a certain design speed is harder than building a new highway, you really can't mess with grades too much, then there is upgrading horizontal curves, which likely would require land.

These days MTO uses a 130 km/hr design speed on 400-series highways.

MTO's own design manual states that 130km/h design speed for design for horizontal curves are "Beyond the normal range of application and are for information only"

Not saying they don't do it. But for jobs our firm has carried out indicate design speeds of 120km/h. And these are on Highways 403 & 404.

I can also tell you that the 407 where it meets the 401 in the west end, that curve doesn't meet the proposed standard for 130km/h, same for 403 & 407 area.

 

[Mulder]

In addition, what does upping the speed limit really do for GTA residents? (This is a GTA forum).

With an average weekday operating speed 20km/h less than the current speed limit though Toronto on the 401, not much. Basically it would only benefit weekend/night drivers in the GTA. Outside the GTA and on the 407? Well, operating speed on the 407 is already 115km/h during peak am rush.

 

[nfitz]

MTO's own design manual states that 130km/h design speed for design for horizontal curves are "Beyond the normal range of application and are for information only"

Not saying they don't do it. But for jobs our firm has carried out indicate design speeds of 120km/h. And these are on Highways 403 & 404.

I can also tell you that the 407 where it meets the 401 in the west end, that curve doesn't meet the proposed standard for 130km/h, same for 403 & 407 area.

Hmm, interesting. It has been a few years since I looked at the design manual. Have they modified this over the years, I thought 130 was pretty much routine, other than the odd curve here or there. I'm curious now what the ones are that I do tend to notice; the curve on 401 eastbound between Odessa and Gardiner's Road in Kingston, climbing down to cross Collins Bay Creek (which doesn't seem as bad since they rebuilt it a few years ago). And the one on 401 at Curry Hill Road (in either direction), just west of the Quebec border. I'm thinking more rural highways here though ... I'm not in the habit of cruising near 130 in the GTA!

 

[Mulder]

Hmm, interesting. It has been a few years since I looked at the design manual. Have they modified this over the years, I thought 130 was pretty much routine, other than the odd curve here or there. I'm curious now what the ones are that I do tend to notice; the curve on 401 eastbound between Odessa and Gardiner's Road in Kingston, climbing down to cross Collins Bay Creek (which doesn't seem as bad since they rebuilt it a few years ago). And the one on 401 at Curry Hill Road (in either direction), just west of the Quebec border. I'm thinking more rural highways here though ... I'm not in the habit of cruising near 130 in the GTA!

I just load up aerial maps in Civil 3D and draw a circle at 650m radius. If the curve fits within the radius, it's 120km/h design speed. If it doesn't it's less. The one near Highway 2 and Brockville for example, is less.

Typically we are supposed to over-design it (don't use the min. radius) I did a quick check and some of the ones you mentioned are better than 650m (barely) But also have spirals so it's hard to tell. The one near Brockville and Highway 2, doesn't have a spiral, and it almost exactly 120km/h.

Basically, if your going around a curve and you feel yourself being pulled away from the curve instead of being guided though it, it wasn't designed for the speed your going.

 

[flyinggoats]

It would have been designed for 80 mph (129 km/hr). The speed limit on 400-series highway used to be 70 mph (113 km/hr), before being dropped to 60 mph (97 km/hr) in the early 1970s.

These days MTO uses a 130 km/hr design speed on 400-series highways.

How are the design standards set for a given speed? Have the highway design standards changed as automotive technology has evolved? I would imagine that a 2015 automobile can handle tighter curves and stop quicker than a 1970 automobile.

 

[nfitz]

I just load up aerial maps in Civil 3D and draw a circle at 650m radius. If the curve fits within the radius, it's 120km/h design speed. If it doesn't it's less. The one near Highway 2 and Brockville for example, is less.

Typically we are supposed to over-design it (don't use the min. radius) I did a quick check and some of the ones you mentioned are better than 650m (barely) But also have spirals so it's hard to tell. The one near Brockville and Highway 2, doesn't have a spiral, and it almost exactly 120km/h.

Basically, if your going around a curve and you feel yourself being pulled away from the curve instead of being guided though it, it wasn't designed for the speed your going.

Ah yes, that Brockville curve is another one!

It's been a while since I've had to design one, but can't you reduce the radius somewhat and increase the superelevation? Or is that already at the limit at 650?

How are the design standards set for a given speed? Have the highway design standards changed as automotive technology has evolved? I would imagine that a 2015 automobile can handle tighter curves and stop quicker than a 1970 automobile.

It's all about the centripetal force. I don't think there'd be any change to design standards based on a 2015 versus 1915 automobile, other than the target veolocity. So unless they come up with some kind of anti-gravity device ... or perhaps even on-board tilting

 

[BurlOak]

The thing with design speed is that it provides the minimum requirements for things like curves, grades, ditches, etc. Often, a segment of highway will not have any aspects that are as low as the design speed. The 401 is not made up of a series of 650m curves, there are straight portions where the design speed for that portion may be well above 130.

The solution is to lower the legal speed at a few critical locations. Nobody says the entire 401 needs to have the same speed. For example, 403 through Hamilton is 90 (or was it 80), while the other parts are 100. The 401 could be 120, with some small segments slower.

I am glad railways do not operate as some describe in this thread, otherwise they would have speed limits for the entire province dictated by one bad curve.

 

[mdrejhon]

It's all about the centripetal force. I don't think there'd be any change to design standards based on a 2015 versus 1915 automobile

The road grip of the wide 2015 wheels and tire treads, are much better than the road grip of the narrow "bike-wheel" style 1915 tires. Also, downforce is greater, given to the way cars are more aerodynamically designed. They can certainly handle 120kph far better today.

Another factor that seems not mentioned here... our winters and our occasionally-crooked highway surfaces. Our roadbed construction is not much more than half as thick as they make it on Germans' Autobahn (Almost a full meter thick of gravel, aggregate, layers, asphalt! They spend more than twice as much per kilometer of freeway lane, too). And sometimes we fix things up only by poorly recycled asphalt layers that crumble after only a couple years.

Better yet (devil's advocate) -- spend the funds adding high speed rail rather than upgrading our 401 to Autobahn standards.

 

[nfitz]

The road grip of the wide 2015 wheels and tire treads, are much better than the road grip of the narrow "bike-wheel" style 1915 tires. Also, downforce is greater, given to the way cars are more aerodynamically designed. They can certainly handle 120kph far better today.

All true, but I don't see that it would make any changes to either the design of curves and superelvation. Hopefully no one ever drives fast enough that "downforce" would be a factor on an expressway curve!

 

[kEiThZ]

It's all about the centripetal force. I don't think there'd be any change to design standards based on a 2015 versus 1915 automobile, other than the target veolocity. So unless they come up with some kind of anti-gravity device ... or perhaps even on-board tilting

Theoretically, if everybody had lane departure assist....

 

[mdrejhon]

All true, but I don't see that it would make any changes to either the design of curves and superelvation. Hopefully no one ever drives fast enough that "downforce" would be a factor on an expressway curve!

In Germany's Autobahn, it's a factor. Minor it may be (compared to racetracks), but a factor, nontheless.

They bank the curves there much better than we do.

Also, one could slightly bank (tilt) the brockville curve to make it much safer at higher speeds. There's some really good banked curves on the Autobahn freeway. 130kph is quite safely navigable in Germany on the brockville radius if running at Autobahn-freeway-quality standards with the traction, quality of roadbed, and banking. I've seen some rather interesting banked curves on some of the better U.S. freeways. Not necessarily to raise the speed limit, but render safer the accidental 130kph overspeeds through Brockville (during a "120kph upgrade elsewhere" situation) in a mitigation measure, even if "90 kph" signs are posted at Brockville. Very prudent safety move. Obviously, not too much banking, since that disorients drivers, but there seems to be almost no bank at all at Brockville compared to other top-notch freeways that was forced to have one sharp radius for one reason or another. They certainly can do better at Brockville, based on what's out there in other countries. What's the maximum banking allowable for Canada's freeways? It's probably tiny, based on what I've seen elsewhere.