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 ModellingNetwork Management & Information CentreWhat is a model?Models are a simplified representationof real lifeWhy 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 AuthoritiesModel BuildModelling ProcedureCalibrationValidationOption TestingModel Build- Site Visits- Carriageway Dimensions- Lane Allocation- TRAFFIC SURVEYSModel BuildBUS NETWORK- Bus Station- Bus Stops- Bus RoutesModel BuildTRAFFIC SIGNALSModel BuildCAR PARKSCalibrationAdjustment of model parameters to reflect real life situations- Vehicle Routeing- Junction CapacityValidationComparison between observed and modelled flowsDepartment for Transport acceptability standardsOption Testing- Quick- As many schemes as you wish- Radical ideas- Excellent statistical output- Real time visual displaysOption Testing050100150200250300350400450500BASE ONE-LANE TWO-LANEModelNumber of VehiclesAM Peak (08:00 - 09:00)PM Peak (17:00 - 18:00)More Lane0100200300400500600BASE ONE-LANE TWO-LANEModelTime (seconds)AM Peak (08:00 - 09:00)PM Peak (17:00 - 18:00)Lammas Lane to Portsmouth Road North420440460480500520540560580BASE ONE-LANE TWO-LANEModelMaximum Queue Length (metres)AM Peak (08:00 - 09:00)PM Peak (17:00 - 18:00)Portsmouth Road SouthboundStatistical Outputs:- Traffic Flows- Journey Times- Queue LengthsOption TestingReal Time Visual DisplaySCOOTSplitplit 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 congestionSCOOTSplitplit Cycleycle Offsetffset Optimisationptimisation Techniqueechnique- Online computer continuously monitors traffic flows over whole network and optimises signal timings to decrease delay and improve traffic flowwww.scoot-utc.comSurreys UTC SCOOT System22 pelican crossings110 junctionsEpsomEwell By-PassKingston RoadEsherSunburyStainesGuildfordGodalmingWokingMeadows GyratorySurreys UTC SCOOT System: Regions10EpsomEwell By-PassKingston RoadEsherSunburyStainesGuildfordGodalmingWokingMeadowsGyratorySurreys SCOOT UTC System: RegionsParamics Model in SCC controlled regionParamics Model in HA controlled regionGodstoneInterchangePast Problems with Modelling SCOOTSIMULATING GATINGWhat is Gating?The control of inflow of traffic into sensitive areas where it is especially important to prevent serious congestionUsed to prevent gyratory systems from being blockedPast Problems with Modelling SCOOTSIMULATING GATINGWhat is Gating?- Gated links store queues- Bottleneck links are maintained free-flowWhen 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 methodsThe SCOOTLinkMicrosimulation passes detector information based on SCOOT signal timingsSCOOT Micro-simulationSCOOT 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-ParamicsProduce Models that will be a Truer Representation of Real LifeHampton Court PalaceCase Study: Hampton Court Flower Show- Annual event in south west London- Worlds largest flower show- 179,000 visitors each yearEsher SCOOT RegionCase 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 EsherCase Study: Hampton Court Flower ShowA3 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 RegionA3 at Esher CommonHampton Court PalaceCase Study: Hampton Court Flower ShowStrategy DesignStrategy Objective:To prevent the queue from Esher town centre extending onto the A3 and interrupting the mainlineHow?By the creation of a special event SCOOT UTC strategy which will operate during the flower showStrategy 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 roomStrategy ImplementationCCTVUTCUTCNMICBlooming 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 problemse.g. Sandown Park, A3 road closures due to incidents?Blooming Marvellous?0%10%20%30%40%50%60%70%80%90%100%07:00 -08:0008:00 -09:0009:00 -10:0010:00 -11:0011:00 -12:0012:00 -13:000%10%20%30%40%50%60%70%80%90%100%07:00 -08:0008:00 -09:0009:00 -10:0010:00 -11:0011:00 -12:0012:00 -13:002007 20080-20mph 20-40mph 40-60mph 60-80mph 80+mphA3 Northbound exit slip at Esher Common

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