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[...]... specialised area beyond basic engineering This book also excludes any reference to railways, other than in the context of on-road light rapid transport and tram systems and also excludes aviation and shipping 1.3 What is traffic engineering? In the introduction to his book Gordon Wells quoted the Institution of Civil Engineers1 for his definition of traffic engineering, that is: That part of engineering which deals... is only appropriate to design a scheme, which deals with the existing problem Therefore, an understanding of existing traffic conditions is fundamental Often however it is equally important to ensure that any traffic engineering solution will be capable of dealing with both existing traffic and the traffic expected throughout the design life of the project For example a junction design should take account... environment for all road users Chapter 11 deals with road safety engineering and discusses concepts of designing in safety and measures to deal with preexisting problems This includes a description of the safety audit procedure, which should now be a mandatory part of any new scheme Chapter 12 deals with traffic calming, describing how traffic engineering measures can be used to manage and reduce the adverse... facility, to ensure that the facility is correctly and safely designed and adequate for the demands that will be placed on it In an existing situation we have to know the present-day demands and patterns of movement, so that the new measure can be designed adequately With a new road or facility, there is obviously no existing demand to base the design on; therefore, we have to estimate the expected demand... data as a basis for design, as the scheme would be over designed for traffic conditions most of the time Generally, traffic surveys should not be planned to measure the ‘peak of the peak’ but to measure the ‘normal’ peak conditions Trunk road surveys may require a full year’s survey of traffic so that the 50th (30th or 200th) highest hourly flow can be determined, and used as the basis for design 2.2 How to... USE Edited by Coded by Checked by Census Single file traffic Census point P C 3.25 3.25 P 3.0 Census stop if required Slow census point Single file traffic Census Fig 2.11 Roadside interview station 20 Traffic surveys As the direction of traffic at a survey station requires the presence of a police officer, it is important to involve the police in the design of the survey, to ensure that they are satisfied... conservative, suggest that, within the next 25 years traffic levels will more than double 1.5 The structure of this book This book has been prepared in the context of traffic engineering as practised in Britain, with references to standard UK designs and legislation That said, many of the basic principles are the same regardless of the country in which they are applied The authors hope therefore that the information... audience who will be able to use and adapt the information contained in this book to their circumstances The book is set out to follow a logical sequence of steps designed to allow the reader to first measure and understand ‘traffic’ and then to design measures to deal with and control it Chapters 2 and 3 deal with surveys Before attempting to undertake any task, it is important to obtain a measure of,... 1 Wells, GR (1976) Traffic Engineering An Introduction, Charles Griffin & Company 2 Department of Transport (1996) Transport Statistics Great Britain, HMSO, London 3 Department of Transport (1996) National Road Traffic Forecasts, 1989, Rebased at 1994, HMSO, London 4 Department of Transport (1989) Highways Economic Note 2, HMSO, London 2 Traffic Surveys 2.1 Introduction Traffic engineering is used to either... be factored up Although the survey technique is designed to have the minimum impact on traffic flow, it is likely that there will be some impact and so it is probably best to plan to record unobstructed traffic flows on another day The potential for this type of survey to disrupt traffic was graphically illustrated by a survey at traffic signals in West London designed to capture traffic using the M4 The peak .