JiscMail Logo
Email discussion lists for the UK Education and Research communities

Help for UTSG Archives


UTSG Archives

UTSG Archives


UTSG@JISCMAIL.AC.UK


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Proportional Font

LISTSERV Archives

LISTSERV Archives

UTSG Home

UTSG Home

UTSG  June 2019

UTSG June 2019

Options

Subscribe or Unsubscribe

Subscribe or Unsubscribe

Log In

Log In

Get Password

Get Password

Subject:

Re: High-volume roads/motorways?

From:

eric britton <[log in to unmask]>

Reply-To:

[log in to unmask]

Date:

Thu, 13 Jun 2019 16:46:13 +0200

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (79 lines)

Sorry to butt in here, but as I read your exchange I am struck once again by how much people like me, basically strategy, policy, climate guys working in our sector, depend on the knowledge and high competence of our engineering colleagues. Newton had it absolutely right: we are standing on the shoulders of giants.

I think about this in my own work quite often. Thank you from the bottom of my heart.

Eric Britton
Coordinato:r The Five Percent Solution 
- Climate.Space.NewMobility.org - 


Eric Britton. [log in to unmask]
MD. EcoPlan International Association
Founding editor, World Streets 
Coordinator. Climate/Mobility Action Plan
T. +336 5088 0787  Skype. newmobility
Follow us on Twitter and Facebook

-----Original Message-----
From: Universities Transport Study Group <[log in to unmask]> On Behalf Of Robert Cochrane
Sent: Thursday, June 13, 2019 3:37 PM
To: [log in to unmask]
Subject: Re: [UTSG] High-volume roads/motorways?

Hi Rob
  
Think you mean "vehicles per lane per day".  And do you mean vehicles or PCUs?  In terms of vehicles, the M25 at J15 with eight lanes carries about 210,000 vehicles per day or about 26,000 vehicles per lane per day.  Using a twelve  hour day to estimate the peak (my guess, but the figures are available), this is a peak of about 2,400 vehicles per hour per lane, which is similar to the UK COBAR maximum recorded hourly values in the 1990s.  Speeds are falling in this regime, so the flow is becoming unstable, So 2,500 vehicles per hour per lane is a good absolute maximum and the rest is the daily flow and peaking.  US figures are slightly less at about 2,200 but that may be a measurement difference.  German Autobahnen in urban areas are similar (how good is your German?) 2,500 gets the flow well into unstable and potential high crash risk territory, but the M25 has a lot of advanced warning signage and also the expected pile ups particularly in poor weather or suddenly changing traffic conditions as any reduction in speed DECREASES the possible traffic flow

Some tunnels and bridges have slightly higher daily figures, as I found in Hong Kong, but these are usually carefully managed pinch points with only four lanes and the jams occur on the approaches where merging is the major issue.  Plus different (lower) peak factors for the daily figure.  The original cross harbour tunnel carries about 118,000 vehicles per day on four lanes or about 29,500 per lane.  Dartford Crossing carries about 160,000 per day on eight lanes, with a higher peak factor as it is not downtown and probably a similar peak figure, although this may also be reduced by the high truck component as it is the London bypass from Dover as well as the London peripheral.

So first, are you looking at managed and tolled pinch points or open untolled road sections as the management problems differ. Second, check whether the figures are vehicles or pcus and one or both directions and the numbers of lanes.  If the answer for vehicles per lane per hour free flow is not between 2000 and 2500 something is wrong.  40% to 50% of this for priority traffic light controlled roads.

So check the definition and the peaking and the truck percentage and in the UK, look no further than the bottom left hand corner of the M25 for free flow and Dartford Crossing for managed and tolled pinch point and in Hong Kong, the original cross harbour tunnel. All have good stats. And consider peak and all day separately.

Best wishes

Robert


The upper limit

On 13-Jun-19 01:37 PM, Rob Bain wrote:
> Hi
>
> I'm looking at some very high-volume roads around the world (at or above 30,000 vehicles/lane/hour).  As you can imagine (from these volumes) the roads are very intensely used from early morning through to late evening.
>
> Do we have examples of roads in the UK where these sorts of volumes (per lane per hour) can be observed?  Or in other countries?
>
> Any thoughts anyone?
>
> Thanks in advance.
>
> Rob
>
> Robert Bain
> RBconsult Ltd
> Investor Support Services
> www.robbain.com<http://www.robbain.com/>
> +44 1732 463314
>
>
> NOTICE OF CONFIDENTIALITY.  This communication is intended only for the use of the addressee and may contain confidential and privileged information. If you are not the intended recipient, you are notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please notify the sender immediately or, alternatively, immediately destroy this communication.
>
>
> ######################################################################
> ##
>
> To unsubscribe from the UTSG list, click the following link:
> https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=UTSG&A=1
>

########################################################################

To unsubscribe from the UTSG list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=UTSG&A=1

########################################################################

To unsubscribe from the UTSG list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=UTSG&A=1

Top of Message | Previous Page | Permalink

JiscMail Tools


RSS Feeds and Sharing


Advanced Options


Archives

September 2019
August 2019
July 2019
June 2019
May 2019
April 2019
March 2019
February 2019
January 2019
December 2018
November 2018
October 2018
September 2018
August 2018
July 2018
June 2018
May 2018
April 2018
March 2018
February 2018
January 2018
December 2017
November 2017
October 2017
September 2017
August 2017
July 2017
June 2017
May 2017
April 2017
March 2017
February 2017
January 2017
December 2016
November 2016
October 2016
September 2016
August 2016
July 2016
June 2016
May 2016
April 2016
March 2016
February 2016
January 2016
December 2015
November 2015
October 2015
September 2015
August 2015
July 2015
June 2015
May 2015
April 2015
March 2015
February 2015
January 2015
December 2014
November 2014
October 2014
September 2014
August 2014
July 2014
June 2014
May 2014
April 2014
March 2014
February 2014
January 2014
December 2013
November 2013
October 2013
September 2013
August 2013
July 2013
June 2013
May 2013
April 2013
March 2013
February 2013
January 2013
December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
November 2011
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010
September 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
October 2009
September 2009
August 2009
July 2009
June 2009
May 2009
April 2009
March 2009
February 2009
January 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007
July 2007
June 2007
May 2007
April 2007
March 2007
February 2007
January 2007
2006
2005
2004
2003
2002
2001
2000
1999
1998


JiscMail is a Jisc service.

View our service policies at https://www.jiscmail.ac.uk/policyandsecurity/ and Jisc's privacy policy at https://www.jisc.ac.uk/website/privacy-notice

Secured by F-Secure Anti-Virus CataList Email List Search Powered by the LISTSERV Email List Manager