Quantifying cars per road?

On Mar 1, 6:25 pm, Wayne Pein wrote:
wrote:
On Mar 1, 10:51 pm, Wayne Pein wrote:

I've critiqued the "Bicycle Compatiblity Index" he

http://humantransport.org/bicycledri...itique_BCI.pdf

....

What is the expected benefit of rating roads on the basis of aggregate
bicyclist perceptions as a function of motor vehicle speed, volume, and
road width? To keep bicyclists off worse rated roads?

I think some people hope that low BLOS ratings will justify spending
money to improve such a road. And it may work, in a few cases.

Of course, the first "improvement" contemplated is often a white bike
lane stripe. That's a problem.

Bicyclists should
be everywhere they are allowed, spreading like a beneficial virus!

Agreed.

What about operational measures such as collision rate, cross traffic
frequency, hilliness, surface condition, directness, etc.? Placing
emphasis soley on the stress of overtaking traffic misses the larger
issues and perpetuates the destructive Fear From the Rear paradigm.

Also agreed.

- Frank Krygowski

On Mar 1, 11:59 pm, Wayne Pein wrote:
Matt O'Toole wrote:

I don't know much about the roads in Germany, but this wouldn't translate
to the US where roads vary a lot in style and width. Very high volume
roads can still be suitable for cyclists if there's enough lane width,
shoulder, and/or a bike lane.

What would be the outcome if a bicyclist used an "unsuitable" road?



For example, compare northern VA (Washington, DC suburbs) with Orange
County, CA. These areas are practically identical in type commercial and
residential development, and in demographics. However OC is eminently
bikeable while NoVA is a disaster. The difference is that all new
development since the 60s in CA has 14' or wider standard lanes, usually
with shoulders or bike lanes in addition; while VA still builds arterial
roads with 12' outer lanes and no shoulders.

Last I checked, my 2' bicycle fit well on a 12' lane.

Wayne

Many of the roads around here are less than 12' yet I still find
riding on them pleasant. But when a dump-truck full of gravel spilling
out passes me at 50mph, followed by a bus, then 30 cars, the
pleasantness starts to wane.

Joseph

On Mar 2, 4:46 am, wrote:
On Mar 1, 6:25 pm, Wayne Pein wrote:

wrote:
On Mar 1, 10:51 pm, Wayne Pein wrote:

I've critiqued the "Bicycle Compatiblity Index" he

http://humantransport.org/bicycledri...itique_BCI.pdf

...

What is the expected benefit of rating roads on the basis of aggregate
bicyclist perceptions as a function of motor vehicle speed, volume, and
road width? To keep bicyclists off worse rated roads?

I think some people hope that low BLOS ratings will justify spending
money to improve such a road. And it may work, in a few cases.

That is my plan. Play to the ego of those in charge. If I can
demonstrate "scientifically" that it is more pleasant to use a bike in
Latvia or someplace the locals would feel insulted to be compared
poorly with then I might get some results.

Of course, the first "improvement" contemplated is often a white bike
lane stripe. That's a problem.

The biggest problem here is that laws mandating that BL's have a
certain (very involved) design means that often in those places where
a BL would actually be nice, it is too expensive. A 200m long stretch
on my commute has a proposed BL, but the cost is proposed to be $6
million USD. For the 10 of us that would use it, this is ridiculous.
In this case, a white line would suffice, or 3' of paved shoulder, but
it is not an option. So we get nothing.

Bicyclists should
be everywhere they are allowed, spreading like a beneficial virus!

Agreed.

What about operational measures such as collision rate, cross traffic
frequency, hilliness, surface condition, directness, etc.? Placing
emphasis soley on the stress of overtaking traffic misses the larger
issues and perpetuates the destructive Fear From the Rear paradigm.

Also agreed.

Me too. The contortions they create in the name of bicycle saftey
(underpasses, fences, gravel) are so much mor of a problem than rear
collisions. Frustrating.

Joseph

On Thu, 01 Mar 2007 22:32:39 +0100, Andrew Price wrote:

Maps produced for cyclists in Germany often classify roads by the
number of motor vehicles per hour which use them. The set I have uses
the following classification:

- over 10,000 vehicles per hour: unsuitable for cyclists

- between 3,000 and 10,000 vph: of limited suitability for cyclists

- between 1,000 and 3,000 vph: suitable for cyclists

- up to 1,000 vph: very suitable for cyclists

Are you sure they mean "per hour", or is it perhaps "per day"? I have
traffic survey maps for my local area, and on a single-carriageway road
anything over 4,000 vehicles per day is unpleasant for cycling, 7,000
per day (eg the road on which I live) is very unpleasant. If the "per
hour" is the peak at commuter time then I would still argue that 3,000
per hour is not suitable for cyclists [1]. Width matters too, and
sight-lines, and whether it's urban or rural (I assume we're talking
rural here).



[1] Assuming two directions, that's almost one every two seconds in the
direction in which you're cycling, which is the recommended gap for
motor vehicles, so this is a continuous stream of motor vehicles at
their minimum spacing. If the traffic is largely uni-directional (as
with many commuter routes), it's a continuous stream at *half* their
minimum spacing!


Mike

On 4 Mar 2007 01:11:41 GMT, Mike Causer
wrote:

[---]

Are you sure they mean "per hour", or is it perhaps "per day"? I have
traffic survey maps for my local area, and on a single-carriageway road
anything over 4,000 vehicles per day is unpleasant for cycling, 7,000
per day (eg the road on which I live) is very unpleasant. If the "per
hour" is the peak at commuter time then I would still argue that 3,000
per hour is not suitable for cyclists [1]. Width matters too, and
sight-lines, and whether it's urban or rural (I assume we're talking
rural here).

I've had another look at the maps - and it doesn't specify! It just
says "für Radfahrer ungeeignet/über 10 000 Kraftfahrzeuge" etc.

You are almost certainly right. I am a train control engineer, and
when we measure subway system capacity, it is in terms of passengers
per hour, so without thinking about it further, I just assumed in the
absence of a unit figure that it must have been "per hour".

As you point out in your analysis, if the densities were per hour, it
just wouldn't bear thinking about, even at 3000 vph.

On Mar 1, 11:14 pm, Matt O'Toole wrote:
On Thu, 01 Mar 2007 22:32:39 +0100, Andrew Price wrote:
On 1 Mar 2007 13:09:55 -0800, "
wrote:

[---]

So any suggestions on ways of thinking about/describing the utility of
roads and their frequency of use?

Maps produced for cyclists in Germany often classify roads by the number
of motor vehicles per hour which use them. The set I have uses the
following classification:

- over 10,000 vehicles per hour: unsuitable for cyclists

- between 3,000 and 10,000 vph: of limited suitability for cyclists

- between 1,000 and 3,000 vph: suitable for cyclists

- up to 1,000 vph: very suitable for cyclists

I don't know much about the roads in Germany, but this wouldn't translate
to the US where roads vary a lot in style and width. Very high volume
roads can still be suitable for cyclists if there's enough lane width,
shoulder, and/or a bike lane. This is more common in Western states.
Eastern states are more likely to have narrow roads with lots of traffic.

For example, compare northern VA (Washington, DC suburbs) with Orange
County, CA. These areas are practically identical in type commercial and
residential development, and in demographics. However OC is eminently
bikeable while NoVA is a disaster. The difference is that all new
development since the 60s in CA has 14' or wider standard lanes, usually
with shoulders or bike lanes in addition; while VA still builds arterial
roads with 12' outer lanes and no shoulders.

Matt O.

I drove my son to a birthday party today a few towns away and to kill
time til it was over I drove around and measured some of the roads
around here. The main roads are between 2.7 and 2.9 meters (8' 10" and
9' 6") and the side roads anywhere from the same down to less than 2
meters (6' 7"). All these roads have no shoulder at all outside the
line. Irritatingly, some of the main roads have lanes much wider, and
have 1m wide shoulders, but these roads are all prohibited for bikes!

These narrow roads can be quite pleasant, but I think the behavior of
motorists is more pronounced, and as I said before a big truck passing
at 50mph is no fun.

Joseph