Project: Development of Generic Variability Models & Validation of M/Way Variability Models

Reference: H016D

Last update: 21/05/2004 15:47:06


This project aims to update and revalidate the 'incident models' and other 'travel time variability' models used by ITEA. Currently INCIBEN And TAMTTV deal with generic cases of travel variability, as applicable to motorways and (to some extent) other road types.


This project intends to deliver advice on incident delays and other time variability encountered on motorways. This information will be included within the Design Manual for Roads and Bridges.


Ove Arup
13 Fitzroy Street, London, W1T 4BQ
+44 (0)207 636 1531

Contract details

Cost to the Department: £390,214.00

Actual start date: 15 October 2001

Actual completion date: 31 December 2003


Journey Time Variability on Motorways
Author: Arup
Publication date: 31/01/2004
Source: DfT Website
More information:

Summary of results

  1. Arup produced a series of working papers culminating in a report setting out
    The appropriate framework and segmentation for journey time variability modelling,
    Prioritised future research requirements and
    Results for two prototype models for forecasting variability on the M6 motorways.

    These placed greater emphasis on the theoretical framework and less on the speculative model fitting to data envisaged in the specification, because of the limitations in the data.
    The results are credible, but dependent upon further data collection/analysis and eventual validation on other motorways.