The London Cycling Centre of Excellence has commissioned Colin Buchanan to undertake some research using VISSIM. At this early stage, the objective is to

assess how cyclists impact junction capacity in Central London. This commission follows the development of the Parliament Square and Victoria Embankment VISSIM model which includes cyclists and motorcyclists. In the view of the political profile of the Parliament Square project and of the density of twowheelers within the area, it was essential that these vehicles were included in the model. The calibration process has already been presented at the 2007 PTV Berlin User Group and the validation of this model has now been finalised. This presentation will detail:

· • The methodology and calibration results of VISSIM with cyclists and motorcyclists on the network showing the level of accuracy of the model and its limitations. The key elements to the calibration were the adjustments of the vehicle driving behaviour and the saturation flow measurements which excluded two-wheelers. Reproducing these measurements in VISSIM involved some Excel programming with the “.COM interface” and a comprehensive calibration exercise.

· • The preliminary results from the research commission will also be detailed. At that stage of the project, the PCU value of two-wheelers will be analysed as well as their impact on general traffic journey times. Moreover, an early analysis of the impact of lane widths on the saturation flow should be detailed.

The objective of this presentation is to show that the lane width, volume of cyclists and general traffic conditions have an impact on the PCU value of cyclists.

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Cross River Tram Modelling and Visualisation – Integration of Operational and Design Evaluation

By Sonal Ahuja (Mott MacDonald) and Rishi Ahuja (Sunovatech)

Email: Sonal.Ahuja?mottmac.com and Rishi@sunova.derafilms.com (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract:

In this paper we present our experiences of microsimulation modelling and visualisation for the Cross River Tram project in Central London. This project has lead to true integration of operation and design evaluation processes.

Microsimulation models in particular VISSIM are increasingly being used to test the operational feasibility of Light Rail Transit (LRT) schemes. Often city centre intersections are plagued with problems of heavy traffic and accommodating conflicting priorities between road users such as pedestrians and general traffic. Local authorities such as Transport for London have serious challenges to provide safe and efficient public transport, a better pedestrian environment while not compensating performance of general road traffic.

Cross River Tram in central London is one of such challenging engineering projects in the UK that aims to relieve parts Central London and bring regeneration to many parts of city. The tram scheme will be state-of-the-art transport system which will ease congestion and provide new link from Camden through central London to Peckham and Brixton. The scheme aims to bring regeneration into local communities and deliver benefits for more than 72,000 very socially excluded residents. The 16.5 kilometres of tramway will carry 7000 passengers per hour per direction. The route will have about 30 stops and tram headway of about 2 minutes.

Cross River Tram aims to deliver the following objectives:

· Relieve tube crowding

· Stimulate regeneration

· Improve accessibility

· Better connection between mainline stations

· Environmentally friendly mode of transport

· Cost efficient

· Connect target areas south of river

· Improve overall system efficiency of highway based public transport

The scheme is expected to cost about £650 million at 2006 cost base and will carry 66 million passengers annually.

Currently Mott MacDonald and Steer Davies and Gleave are involved in a consortium developing detailed design and testing operational feasibility of the scheme. As a part of appraisal process several models including a microsimulation model of the entire route is being developed and tested.

The microsimulation model for the future operation of the tram is being used to test signal operations and tram priority on the proposed routes. It is linked to the strategic STAURN model of the area and is truly multimodal representing all demand segments including cars, goods vehicles, buses, cyclists, motor cyclists and pedestrians. In addition the models are also linked to TRNSYT signal optimisation models via a two way feedback process to design efficient demand dependent priority traffic signal settings.

The VISSIM simulation model of the route has been calibrated and validated to local London driver behaviour using video surveys. The models are also being used to assist in development of tram time tables, refine detailed design, terminal layouts and redesign efficient traffic signals settings.

One of the main objectives of the model is to future proof the scheme against traffic and utilise the models not only for evaluation of engineering options but to be a design aid in visualisation of the scheme that can be used to demonstrate the future operations. To achieve the above the microsimulation models are being linked to ultra realistic 3D virtual reality (VR) models created for the tram corridor. These are proposed to be used future public consultation exercises.

The visualisation of the core route not only includes 3D representation of traffic and future tram operations but detailed 3D visualisation of more than 1800 buildings along the route. In addition, a VR model of street furniture such as bus stops, tram stops, street lighting and other elements has been integrated in the model. The model contains realistic road markings and street paving textures.

The 3D VR model is also being used as a two way design tool using which engineers can visualise the exact shape and design of the tram, its textures, kinematic envelop and swept path. This VR process has also helped not only in visualisation refinement of engineering options but help urban design issues as well.

We present here our experiences, the process, methodology and results and benefits of integration simulation models with other optimisation, modelling and visualisation tools to achieve a winning solution for a complex engineering problem.

The authors would like to thank Transport for London, the project design teams of Mott MacDonald, SDG, Sunovatech and Gillespies for support for this publication and the project.

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Enhancing Mobility: The Role of Micro-Simulation in Option Development

By Ed Downer (Jacobs Consultancy) and Anthony Robinson (Jacobs Consultancy)

Email: Edward.Downer?jacobs.com, Anthony.Robinson@jacobs.com (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract

This paper aims to review the process by which micro-simulation modelling can be used in the option development process for transport schemes. Using the case study of the Wheatsheaf Gyratory in Sunderland, the presentation will focus on the process and methodologies used, as well as looking at how the model outputs were put to more advanced use.

The presentation is split into four sections; Identifying the Problem, Testing Solutions, Refining the Solution and Quantifying the Benefits. In the first section, the background and scope of the project will be outlined, including how the Base Model was initially constructed. The second section will deal with the development of the Do Something models, and review the initial findings of the more “conventional” evaluations. “Refining the Solution” will detail how sensitivity testing was undertaken on the model using VB scripts to create process batch files. The final section will summarise how the model outputs were then processed for use in TUBA to give an overall Benefit to Cost Ratio for the preferred scheme.

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Interfacing London’s Urban Traffic Control System with VISSIM

By John Green (TfL) and Mehdi Langroudi (TfL)

Email: John.Green?tfl.gov.uk, Mehdi.Langroudi?tfl.gov.uk (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract:

Transport for London (TfL) in collaboration with Transport Research Laboratory (TRL) have developed a two way interface linking TfL's bespoke SCOOT (Split Cycle and Offset Optimisation Technique) system and VISSIM.

Directorate of Traffic Operations, within Surface Transport division of Transport for London, is responsible for the management and operation of London’s 6,000 traffic signals and their accompanying systems, technologies and equipment. The Urban Traffic Control (UTC) team within DTO is responsible for designing and maintaining signal timings for 2,900 of London’s traffic signal installations linked to a central computer, to manage the safe movement of people and goods on London’s busiest streets. Signal timings at one third of these centrally controlled junctions are optimised by TfL's customised version of SCOOT, a dynamic system that changes signal timings automatically in response to changes in traffic flow.

VISSIM is used extensively within the Directorate of Traffic Operations (DTO) to assess the impact of schemes and to assist with the timing review programme.

Due to the complexity and dynamic nature of the SCOOT model and UTC systems it has been impossible, until now, to simulate them offline in VISSIM; it was equally impossible to model the effects of advanced SCOOT features such as bus priority and gating.

This paper outlines the development of the interface, its features and plans for future developments.

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Haymarket Interchange Feasibility Study Future Vision

By Jeff Knight (Halcrow Group)

Email: Knightj?halcrow.com (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract:

Haymarket is Scotland’s fourth busiest railway station with almost 4 million passengers passing through each year. Ongoing and future developments across the city will generate substantially more public transport passenger movements through the area which will impact on its effectiveness.

In the coming years two major infrastructure projects are expected to be implemented: Haymarket Accessibility Project and the Edinburgh Trams Project. The Edinburgh tram project was modelled by Colin Buchanan Partners on behalf of tie Ltd using a VISUM and VISSIM model. The Haymarket Feasibility study undertaken by Halcrow and built on this platform to model in detail the complex range of competing travel demands and movements at the interchange, combining a VISSIM traffic model (cordoned out from VISUM model), a microsimulation pedestrian model (PAXPORT), and public transport demand forecasts for 2011 and 2031.

The study objectives were to provide an attractive multi-modal transport interchange that will accommodate forecasted levels of demand from all transport and related pedestrian trips; and to maximise the opportunities for private sector funding and property redevelopment that will help achieve these objectives

The results were visualised in 3D Studio Max, by combining for the first time a laser scanned geomatic 3D model of the entire study area, LIDAR arial survey data, general massing data of buildings within 800 metres, a fully rendered 3D architectural model of the station interchange, tram facilities, pedestrian movements (initially modelled in PAXPORT microsimulation model) and VISSIM. The VISSIM model simulated the interaction between pedestrian movements and traffic movements and output data in a format that was exported to Studio Max to generate photo-realistic 3D movie images of the complex pedestrians, public transport and trafficmovements in the context of the proposed 2031 interchange.

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Maidstone Local Development Framework Core Strategy Transportation Study

By Shaleen Srivastava (Jacobs Engineering UK Ltd.) and Kakpo Adoko (Jacobs Engineering UK Ltd.)

Email: Shaleen.Srivastava?jacobs.com , Kakpo.Adoko?jacobs.com (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract:

The Maidstone Local Development Framework (LDF) Transport Strategy VISUM study forms an important element of the Transport Strategy developed to support the Maidstone Local Development Framework which is moving towards Public Inquiry this year. Consequently all the work done is made sufficiently robust to satisfy a high degree of possible scrutiny by other agencies.

The VISUM based Maidstone LDF Transport Strategy study is broken into two elements;

· Multimodal Model Transport Study;

· A Bus Infrastructure and Viability Study.

The study is to support the work for the LDF which has identified a Core Strategy for highway and bus improvements in Maidstone.

The four defined aims of the study are as follows:

· Assess the effect of the proposed South East Maidstone Strategic Link in dealing with the development proposals in the Core Strategy Preferred Option, and its impact on the rest of the road network.

· Assess the improvements needed to bus route infrastructure to support the development proposals

· Provide a tool to allow the assessment of alternative development to the Preferred Option, whether by the Borough Council or by developers.

· Provide future base for the proposed link to the Maidstone Traffic Management Centre.

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Latest developments and projects in Traffic Management and Traveller Information

By Arnd Vogel (PTV)

Email: Arnd.Vogel?ptv.de (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract:

PTV is currently involved in several projects which aim to create regional Traveller Information Portals. These portals provide information about the current traffic conditions, roadworks, jams and other incidents as well as forecasts of traffic conditions for different time scales. The information is delivered to the user in form of maps and lists and as an input for dynamic route planners which account for the travel times resulting from the road conditions. Examples of these portals are www.bayerninfo.de which covers Bavaria, www.ruhrpilot.de which covers the conurbation of the Ruhr area or ITS Vienna region for Vienna, Austria.

All of these portals require sophisticated data processing in order to provide the information to the end user. A stack of different procedures for traffic state estimation and forecast on different timescales have been created. Usually, roadside detectors supply the basic data on local traffic flow and speeds. Distinct models such as ASDA/FOtO for highways or MONET for urban networks accomplish the task to extend these local measurements to network-based data about travel times, congestion and Level of Service. Where no measurements are available, algorithms based on dynamic traffic models such as Validate are used to fill the gaps. Historical time series of detector data, traffic models and the available information on planned roadworks form the basis of traffic forecast for time frames from one hour to weeks or even months ahead. All the results from the different models and for the different time frames then need to be harmonized and merged into a homogenous representation for the end user.

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Application of VISSIM in Pedestrian Modelling

By Saikat Bose (Mott MacDonald) and Sonal Ahuja (Mott MacDonald)

Email: Saikat.Bose?mottmac.com , Sonal.Ahuja?mottmac.com (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract:

Pedestrian Modelling is a field gaining increasing attention from transport modellers. In past, transport planner modellers have concentrated on modelling of vehicular modes alone. In most transport models pedestrian needs have been neglected. There is a realisation in transport planning profession, that without adequate importance being given to pedestrians, no model can truly depict the complete reality. Hence these solutions are only partial in nature.

Recently, three major pedestrian modelling projects were undertaken by Mott MacDonald. We used VISSIM effectively used to depict the existing and proposed interaction between pedestrians, cyclists and mechanised modes of travel. These models were able to highlight the capability of VISSIM to adequately handle the movement of pedestrians, both alongside and across traffic and movements in open spaces. This presentation gives the details of the three high profile case studies.

Case Study 1: Cambridge Railway Station CB1 Development

The Cambridge Railway Station pedestrian model was developed to analyse the impact of the proposed billion pound CB1 development on the movement of pedestrians, cyclist and vehicles around the station forecourt area.

This study, incorporated a before and after development analysis that clearly depicted the impacts of the proposed developments on the movement of pedestrian & cyclists. The models included dynamic assignment of pedestrians and were able to replicate the route choice based on least cost paths.

VISSIM was used to precisely depict the movement of pedestrian and vehicles under normal traffic conditions and in pedestrian priority zones. The model was presented and exhibited in the CB1 public consultation process and helped the developers in answering various traffic related queries raised by the counsellors and the local public and interest groups

Case Study 2: Bridge City North Railway Station, Durban, South Africa

The Bridge City Railway Station, pedestrian study was used to analyse the movement of pedestrians within the proposed railway station in Bridge City, Durban, South Africa. Various models were developed to analyse the operation of the station under different development proposals to assess the optimal operational situation that resulted in least queuing for pedestrians through ticket checking and other queuing areas.

The VISSIM based model, adequately represented the movement of pedestrian within the station (at the concourse/ platform levels), queuing of passengers at ticketing counters and at turntiles, the movement of passengers along staircases/ escalators and also the queuing of passenger waiting for trains. A total of over 20,000 pedestrians were simulated in the peak hour.

Case Study 3: Guidelines for Installation of Scramble Pedestrian Signals at Intersections, California, USA

In this study, VISSIM pedestrian models have been used for development “Guidelines for Installation of Scramble Pedestrian Signals at Intersections” at major intersection within Oakland City Centre area. The methodology adopted for this study included the development of base year models using VISSIM representing the operation of an intersection under conventional pedestrian crossing.

To test the impact of with and without scramble signals the traffic volumes of the pedestrians or vehicular traffic or both were increased representing Level of Service (LOS) A to LOS E to test the performance of the intersection.

The key performance indicators of the intersection such as average delay time per vehicle, total delay (vehicle and pedestrian), average speed, average travel time to cross the intersection, total distance, etc. were analysed and compared.

The guidelines were developed based on the analyses of these indicators. Our findings conclude that scramble intersections are only effective when the Pedestrian LOS exceeds C.

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BRAVISIMO: Applying WebTag to the BRAcknell VISum Integrated Multi Modal MOdel

By Simon Bingham (WSP) and Sergio Grosso (PTV UK)

Email: Simon.Bingham?wspgroup.com, Sergio.Grosso?ptv-newcastle.co.uk (please substitute ‘?’ with ‘@’ – spam preventing measure)

Abstract:

WSP were commissioned to undertake the development of a multi-modal model to assess the impact of developments and development plans within the urban area of Bracknell. The model entails a four stage structure compliant with current WebTag guidance on model form and is operated within VISUM software providing a holistic environment both for demand modelling and public transport/highway assignment. The model itself will be developed to accommodate the requirements and sensitivity analysis required in order to achieve central government funding.

The main requirement is that the transport model should be built on a behavioural basis that determines the travel demand from the underlying characteristics of the transport supply and the characteristics of the travellers in the area. In addition the model requires a detailed representation of the highway network in and around the centre of Bracknell to accurately reflect current and changing levels of congestion whilst also being able to take account of the external influences of Reading, Heathrow and outer London and the Thames Valley

Developing the model to be WebTag compliant has led to some re-engineering of the I/O flows between modules in VISUM and a different implementation of skim matrices for mode choice/distribution indicating the flexibility of VISUM in model development. Various aspects of the implementation will be discussed.

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