Traffic Modelling Network Management Information Centre Management Information Centre. ... 22 pelican crossings 110 junctions. Epsom ... Case Study: Hampton Court Flower Show

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  • Traffic Modelling

    Network Management & Information Centre

  • What is a model?Models are a simplified representationof real life

    Why do we model?Modelling is a tool that enables us to:

    Gain a greater understanding of past and present situations Foresee the effects of altering the current transport network & test

    radical solutions Minimise the potential for planning to go wrong!

  • S-Paramics Microsimulation An internationally renowned road traffic

    microsimulation modelling package

    Used to analyse present and future traffic conditions

    Real time visual display

    Wide variety of statistical output

    Widely used in Local Authorities

  • Model BuildModelling Procedure

    Calibration

    Validation

    Option Testing

  • Model Build

    - Site Visits

    - Carriageway Dimensions

    - Lane Allocation

    - TRAFFIC SURVEYS

  • Model Build

    BUS NETWORK

    - Bus Station

    - Bus Stops

    - Bus Routes

  • Model Build

    TRAFFIC SIGNALS

  • Model Build

    CAR PARKS

  • CalibrationAdjustment of model parameters to reflect real life situations

    - Vehicle Routeing

    - Junction Capacity

    ValidationComparison between observed and modelled flows

    Department for Transport acceptability standards

  • Option Testing

    - Quick

    - As many schemes as you wish

    - Radical ideas

    - Excellent statistical output

    - Real time visual displays

  • Option Testing

    0

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    BASE ONE-LANE TWO-LANE

    Model

    Num

    ber o

    f Veh

    icle

    s

    AM Peak (08:00 - 09:00)PM Peak (17:00 - 18:00)

    More Lane

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    100

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    BASE ONE-LANE TWO-LANE

    Model

    Tim

    e (s

    econ

    ds)

    AM Peak (08:00 - 09:00)PM Peak (17:00 - 18:00)Lammas Lane to Portsmouth Road North

    420

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    BASE ONE-LANE TWO-LANE

    Model

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    imum

    Que

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    AM Peak (08:00 - 09:00)PM Peak (17:00 - 18:00)

    Portsmouth Road Southbound

    Statistical Outputs:

    - Traffic Flows

    - Journey Times

    - Queue Lengths

  • Option Testing

    Real Time Visual Display

  • SCOOT

    Splitplit Cycleycle Offsetffset Optimisationptimisation Techniqueechnique

    - Co-owned by Peek Traffic Ltd, Siemens Traffic Controls and TRL Ltd

    - Used in > 200 cities in UK & Worldwide

    - Adaptive traffic management method which minimises traffic problems, especially congestion

  • SCOOT

    Splitplit Cycleycle Offsetffset Optimisationptimisation Techniqueechnique

    - Online computer continuously monitors traffic flows over whole network and optimises signal timings to decrease delay and improve traffic flow

    www.scoot-utc.com

  • Surreys UTC SCOOT System

    22 pelican crossings

    110 junctions

  • Epsom

    Ewell By-PassKingston Road

    Esher

    SunburyStaines

    Guildford

    Godalming

    Woking

    Meadows Gyratory

    Surreys UTC SCOOT System: Regions

    10

  • Epsom

    Ewell By-Pass

    Kingston RoadEsher

    SunburyStaines

    Guildford

    Godalming

    Woking

    MeadowsGyratory

    Surreys SCOOT UTC System: Regions

    Paramics Model in SCC controlled region

    Paramics Model in HA controlled region

    GodstoneInterchange

  • Past Problems with Modelling SCOOTSIMULATING GATING

    What is Gating?

    The control of inflow of traffic into sensitive areas where it is especially important to prevent serious congestion

    Used to prevent gyratory systems from being blocked

  • Past Problems with Modelling SCOOTSIMULATING GATING

    What is Gating?

    - Gated links store queues

    - Bottleneck links are maintained free-flow

    When the bottleneck links reach a defined saturation, SCOOT gating operates automatically &

    reduces green times on gated links

  • Past Problems with Modelling SCOOTMODEL VALIDATION & OPTION TESTING

    - Schemes may have been dismissed as unable to work in heavily congested areas under fixed time control

    - Sceptical Results?

    SCOOT has been shown to decrease vehicle delay by typically 12% over alternative non-adaptive methods

  • The SCOOTLinkMicrosimulation passes detector

    information based on SCOOT signal

    timings

    SCOOT Micro-simulation

    SCOOT passes signal timings

    based on detector flow

    (Siemens, 2005)

  • Why SCOOTLink?

    - Surrey contains many SCOOT regions

    - 8 Regions have S-Paramics Models

    - Past experience of simulating SCOOT regions

    - Increase functionality & efficiency of S-Paramics

    Produce Models that will be a Truer Representation of Real Life

  • Hampton Court Palace

    Case Study: Hampton Court Flower Show

    - Annual event in south west London

    - Worlds largest flower show

    - 179,000 visitors each year

  • Esher SCOOT Region

    Case Study: Hampton Court Flower Show

    - An additional 21,000 vehicles pass through Esher during the 6-day event

    - Peaked nature of traffic flow poses a problem in the town of Esher

  • Case Study: Hampton Court Flower Show

    A3 at Esher Common

    -A queue extends back from Esher over 2km to the A3 trunk road

    -Between 9am and 12pm the queue reaches the A3 mainline

    -This results in erratic driver behaviour and dangerous driving conditions

  • Esher SCOOT Region

    A3 at Esher Common

    Hampton Court Palace

    Case Study: Hampton Court Flower Show

  • Strategy DesignStrategy Objective:

    To prevent the queue from Esher town centre extending onto the A3 and interrupting the mainline

    How?

    By the creation of a special event SCOOT UTC strategy which will operate during the flower show

  • Strategy Testing

    - Used a traffic model to test various strategies

    - The modelling enabled quick assessment of many strategies within a controlled environment

    - It was found that a gating strategy was the most effective which:

    Provides more green time for traffic approaching Esher from the A3 when the congestion level here is greater than 10%

  • - On-street trials were performed

    - Unlikely to be perfect, as a model is not a perfect copy of real life!

    - Operate 08:00 12:00 hours

    - Implemented and monitored from the NMIC control room

    Strategy Implementation

    CCTV

    UTCUTC

    NMIC

  • Blooming Marvellous?

    - In 2008 it met the study objective with no queuing on the A3 mainline

    - Strategy was operated as predicted by the traffic model

    - No public complaints

    - Its success means that it can now be used for other events, bothplanned and unplanned, which create similar traffic problems

    e.g. Sandown Park, A3 road closures due to incidents?

  • Blooming Marvellous?

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    07:00 -08:00

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    0%

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    07:00 -08:00

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    2007 20080-20mph 20-40mph 40-60mph 60-80mph 80+mph

    A3 Northbound exit slip at Esher Common

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