Project: Travel Time Variability Phase II

Reference: H016B

Last update: 24/05/2004 15:49:06

Objectives

An earlier project (H016A) developed a provisional methodology to assess travel time variability and thus establish whether the economic benefits from some road improvements were being underestimated and therefore not fully reflected in evaluation. This follow-on research aims to develop further methods to estimate travel time variability and to refine the methodology for calculating variability due to incidents on inter-urban roads.

Description

An earlier project (H016A) developed a provisional methodology to assess travel time variability and thus establish whether the economic benefits from some road improvements were being underestimated and therefore not fully reflected in evaluation. This follow-on research aims to develop further methods to estimate travel time variability and to refine the methodology for calculating variability due to incidents on inter-urban roads.

The work is split into three elements:

(i) short term advice on the measurement of incident-related travel time benefits. This was developed by the John Fearon Consultancy using incident data collected by TRL in 1994/95. The resultant draft advice note on travel time variability due to incidents is being tested on a number of projects and the need for further development is being reviewed;

(ii) incorporating travel time variability in traffic assignments and traffic demand modelling. This contract was let in January 2000 for completion in December. The associated literature review was due for completion in July 2000;

(iii) the collection of travel time variability data during 2000/01 to validate the methodologies of estimating travel time variation. The first part of this is expected to be let in the summer and the rest is expected to commence in autumn 2000. This work will be supported by work to be carried out by the Highways Agency as part of its outward facing research programme.

Contractor(s)

University of Leeds
School of Geography, Woodhouse Lane, Leeds, LS2 9JT
0113 233 3300

Mott MacDonald
Devon House, 12-15 Dartmouth Street, London, SW1H 9BL
20 7340 2250

Imperial College London
Exhibition Road, London , SW7 2AZ
020 7589 5111

Contract details

Cost to the Department: £135,300.42

Actual start date: 21 January 2000

Actual completion date: 30 April 2004

Publication(s)

Incorporating Variable Travel Time Effects in Route Choice Modes
Author: A. Gordon, T van Vuren and D Watling et al
2001
Source: ETC 2001 Cambridge

Assessing Measures which Reduce Incident-Related Delays and Travel Time Variability
Author: T. van Vuren and S. Ahuja
2002
Source: ETC 2002 Cambridge

Supply Models for use in Modelling the Variability of Journey Times on the Highway Network
Author: J. Bates, J. Fearon and S. Porter
2002
Source: ETC 2002 Cambridge
More information: http://www.dft.gov.uk/pgr/economics/rdg/jtv/fmvhjt/

Summary of results

  1. The results showed how TTV could be reflected as anon-linear term in assignment and the scale of the differences in assigned flows.