Talk:Continuous-flow intersection

Definition

What is a "turn conflict?"--Greatjones 00:45, 6 February 2006 (UTC)[reply]

When the path of one vehicle intersects with the path of another vehicle. --Thisisbossi 15:31, 4 October 2006 (UTC)[reply]

Good source for info

[1] --SPUI (T - C) 03:06, 23 July 2006 (UTC)[reply]

Agreed. Added it into the External Links. --Thisisbossi 15:31, 4 October 2006 (UTC)[reply]

My recent revert

Perhaps I am nitpicking on semantics, but I just undid an edit that replaced "Motorists sometimes cite discomfort" with "Motorists sometimes cite safety issues". In the same sense as a square is a rectangle, but not vice-versa; safety concerns include discomfort, but discomfort does not necessarily indicate a safety issue. An adequately designed CFI can still violate driver expectancy due to the "keep left" configuration and therefore will cause discomfort to motorists, but such does not necessarily translate to a safety risk in excess of other typical intersections.

Also, included in the same revert, was the mention of using Jersey walls for delineation. These are not typically recommended due to the crash risk that they pose in the event of collision and also due to sight distance limitations. While their use is definitely feasible and I'm sure that there is or will be a CFI using such barrier walls, the phrasing used appeared to indicate that Jersey walls are a requirement for an adequately-designed CFI.

Lastly, length is not the sole trait of an adequately-designed acceleration lane, though I will agree it is an important trait. I feel that my phrasing provides a more vague approach rather than singling out only one trait. On a CFI involving lower speeds, length tends to become less relevant; rather the form of merge control becomes a higher priority. Turning radii and lane widths are other important factors.

--Thisisbossi 05:47, 2 February 2007 (UTC)[reply]

Agencies must pay royalites?

It seems U.S. agencies don't have to pay because this US patent expired October 15, 2003.

http://portal.uspto.gov/external/portal/pair enter 5049000 as the patent number.

Juxtapos99 10:51, 18 October 2007 (UTC)[reply]

I Checked this out, and it seems to be true. I'll add this to the article. — Val42 21:08, 19 October 2007 (UTC)[reply]

Concerns about clarity

I find the narrative and the monochrome diagram to be quite confusing. I have good spacial skills but am not a traffic professional or maven. Perhaps a color-coded diagram would be the single most helpful improvement. --Jdmstl 03:56, 31 October 2007 (UTC)[reply]

I'm planning on redoing the diagram because of other issues, but tell me about this color coding idea that you have. — Val42 05:19, 2 November 2007 (UTC)[reply]

I think the comment requests that each movement be color-coded. For example, the path of northbound lefts might be blue; northbound throughs red; eastbound lefts yellow; etc... --Bossi (talk • gallery • contrib) 21:12, 17 December 2007 (UTC)[reply]

"outside Mexico" vs "in the US"

I changed the section title "Locations outside Mexico" to "CFI Locations in the United States". I found the title confusing when reading the article. Though the article mentions the original development being in Mexico, there's nothing to indicate that all other CFI implementations are in Mexico, leaving it open whether examples exist other than in MX and US. If there really are no others, then it would make sense to clarify this both in the text and by further altering the section title as appropriate.Paleolith (talk) 01:35, 1 November 2010 (UTC)[reply]

US versus the world... Since Wikipedia is deliberately a global resource, the authors of this article should reference the fact that CFIs are an import from Mexico. That would certainly help clarify your "outside Mexico vs in the US" problem. Obviously, Wikipedia is user-based, but you should at least include one original reference. It's almost like claiming that Shakespeare was from Connecticut. —Preceding unsigned comment added by 99.254.16.135 (talk) 11:49, 16 March 2011 (UTC)[reply]

Description is useless and confusing

The top photo shows cars on a road and is completely useless for the purposes of the article. The second photo shows a couple of lanes that could be from any intersection of two roads anywhere and is completely useless for the purposes of the article. The small diagram, which I have studied in the "no higher resolution available" version, is confusing and therefore useless. As far as I can tell from the diagram currently in this article, three lanes of southbound traffic pass jaggedy-like through the intersection then smash into two lanes of oncoming traffic that intend to turn left, by trying to be the same place at the same time, causing fatal accidents every few minutes, and nobody with any sense would seriously consider building this type of intersection. Now, either this article needs to have a sentence at the top saying that this whole article is a hoax, or it needs a clear diagram showing how this intersection design could possibly be sensible. By contrast, see Diverging_diamond_interchange or Michigan_Left which use clear diagrams and aerial photos to show the traffic flow. Don't bother replying here; if the article can be fixed, fix it. 76.21.81.159 (talk) 05:16, 2 August 2011 (UTC)[reply]

Safety, capacity, delay reduction and design options (for continuous flow intersections)

I have analysed and sketched continuous flow options for 24 sites in my previous job and to this date my old employer has seriously considered two of them but there is no commitment. In all cases, there were major capacity and delay benefits (generally 50% capacity increase and 50% delay reduction). Now I realise that there is a theoretical safety benefit that is also huge. This is supported by the one site in Utah for which there is impressive crash data. I have published sketches and theory on my web site at flowcontinuous.com. Also there are simulations by my colleague and references to newspaper articles. There are many options in the design and I keep making improvements, many of which are at variance with the Utah examples (I think they are only removing turns from one road and not getting further capacity, safety & delay benefits from removing the other turn phases.) Discussion and brochure from Utah is also at my web site. Further, the public have access to Victoria, Australia crash data and can test whether the Utah constraints of access control are out weighed by the benefits. At this point, I am thinking that contributing to the wiki might be a better way to go. Any advice on direction would be appreciated. Kindest regards Cleeland John (talk) 09:43, 4 September 2012 (UTC)[reply]

The disadvantages of the parallel flow intersection is that (a)it still requires four phases at the main intersection and so has double the delay. (b) It also interrupts both directions on the departures and so messes up the linking with all three intersections on each through route. — Preceding unsigned comment added by Cleeland John (talk • contribs) 03:54, 1 January 2013 (UTC)[reply]

The PFI

I think that a new article should be added that details the Parallel Flow Intersection. It is like this one, but driver expectancy is higher due to the traditional turn pockets. Diagram here: http://www.fhwa.dot.gov/publications/research/safety/09060/images/09060_img_166.jpg as you can see, it moves the turn lanes and turns them into kind of like slip lanes. I don't have the time or the patience to make an article myself. 209.112.137.248 (talk) 22:53, 6 October 2012 (UTC)[reply]

Use of coordinates

The coordinates moved inline by Hans Haase make it difficult to read the prose. As far as I can tell, most coordinates are added to Infoboxes. They seem very helpful positioned here, but is there some other way to implement them? Thanks. --Chaswmsday (talk) 14:22, 3 February 2013 (UTC)[reply]

Thx, move the {{coord|....}} to better place or use the ##, refer the help on the coord template for alternative printout. I think the coordinates should be visible for offline use of the article. It would not fit the screen. Better now? --Hans Haase (talk) 20:27, 3 February 2013 (UTC)[reply]