The following are summaries of papers published in other parts of ICE Proceedings during 1999 that readers of Municipal Engineer may find of interest. You can obtain back issues directly from the ICE's publications division, Thomas Telford Publishing (telephone +44 (0)20 7665 2460, fax +44 (0)20 7537 3631, e-mail: ttsales@ice.org.uk). Summaries of all papers in ICE journals are also freely available and fully searchable at the `journals online' section of the ICE web site (www.ice.org.uk/jol).
The Hulme Arch Bridge, Manchester
N. Hussain, I. Wilson
Proceedings of the Institution of Civil Engineers, Civil Engineering, 132, 1999, February, 2–13
The award-winning Hulme Arch Bridge in Manchester is a showpiece for the civil engineering profession. Though small in scale, this new cable-stayed road bridge in the heart of the Hulme regeneration area is a perfect example of how imaginative design combined with leading-edge engineering technology can be used to create a landmark structure which captures the public's imagination. The 52 m span is supported by a unique single diagonal parabolic arch made from a tapering trapezoidal steel box section coated in aluminium paint. This paper describes the design and construction of the various elements of the bridge and discusses, in particular, the measures taken to avoid plate buckling and to control concrete foundation temperatures.
Road layout design standards and driver behaviour
G. Maycock, P. Brocklebank, R. Hall
Proceedings of the Institution of Civil Engineers, Transport, 135, 1999, August, 115–122
This paper describes experimental studies, undertaken for the Highways Agency, in which the role of driver characteristics in three specific components of the driving task-speed choice, emergency braking and overtaking-have been explored. The purpose of the work was to provide the design engineer with a more detailed insight into the characteristics of drivers using the roads and their performance in critical situations. A simple stratification of car drivers has been derived from speeds measured at a sample of trunk road sites in Great Britain in combination with the personal characteristics of the drivers obtained by postal questionnaire. The emergency stopping study explored the determinants of emergency stopping performance using a simple simulator, and overtaking behaviour on single carriageway roads was studied both in a simulator and on the road.
Simple models for traffic jams and congestion control
C. Wright, P. Roberg-Orenstein
Proceedings of the Institution of Civil Engineers, Transport, 135, 1999, August, 123–130
It would be useful to know more about the spatial structure of traffic jams and how they propagate, so that techniques can be developed for inhibiting and dispersing them. The authors have analysed the development of traffic jams caused by blockages or incidents on idealized rectangular grid networks, and although the models are not very realistic, they reveal some basic features of jam formation and point to methods for controlling them. With hindsight, the principles seem to apply qualitatively to real traffic situations as well. The models show that the structure of jams on idealized grid networks can follow either of two regular patterns. Also, jam growth can be inhibited by reallocating queue storage space between turning traffic and ahead traffic, and by shortening the length of the segregated queue storage space. Containment, however, and the prevention of gridlock, are two distinct objectives that conflict with one another. Once a jam has formed, in many cases it can be dispersed by applying a gating strategy around the affected area in combination with temporary turn bans at selected junctions near to the site of the blockage. Recently, the models have been extended to two-way rectangular grid networks. The aim of this paper is to summarize the results and draw together some conclusions that have emerged from the project as a whole. Finally, the paper reviews the practical implications of the model and assesses the potential for inhibiting and dispersing jams on real networks using low-cost methods.
A network level pavement management system for China
Y. Pan, H. R. Kerali, M. S. Snaith
Proceedings of the Institution of Civil Engineers, Transport, 135, 1999, August, 131–137
The China pavement management system (CPMS) is the product of one of the Government of China's national key research projects conducted between 1986 and 1990. Thereafter, the Ministry of Communications set out to implement the CPMS for managing road maintenance throughout the country by the year 2000. The first phase, to 1996, saw its introduction to 174 000 km of trunk roads in 14 provinces. This resulted in a significant improvement in the management of road maintenance by presenting investment alternatives to provincial engineers in a coherent fashion. The CPMS comprises three components: a comprehensive database, a network level maintenance management system and a project level maintenance management system. This paper focuses on the methodology and procedures employed in the network level system including data acquisition, pavement condition evaluation, performance prediction, maintenance needs analysis, budget assignment and sensitivity analyses.
Personal public transport
M. V. Lowson
Proceedings of the Institution of Civil Engineers, Transport, 135, 1999, August, 139–151
Analysis of current types of public transport shows that they are mismatched to geography of modern towns, the form of which is dominated by the availability of the car. A new kind of public transport has been sought which can meet both the requirements of the user for effective transport, and the non-user for an exemplary urban environment. It has been found that exploitation of existing technologies can meet these requirements in a new type of transport. This can be described as a personal automatic taxi system running on its own guideway network. It is shown that this can offer effective transportation at energy and emission costs which are reduced by an order of magnitude compared to the current car-road system. Initial studies also suggest that the new system can be economically viable. The new transport system, which is an improved version of types previously proposed under the general description of personal rapid transit, appears to offer an attractive and genuinely sustainable alternative to the car for urban transport in the next century.
The estimation of highway geometry for road accident analysis
K. Lupton, P. Zhang, C. C. Wright
Proceedings of the Institution of Civil Engineers, Transport, 135, 1999, November, 173–184
There is no documentation recording the geometric alignment of the greater part of Britain's road network. Highway geometry is an important factor in road accidents, particularly in rural areas where speeds are high and injuries tend to be severe and numbers of sites requiring investigation are large. Hence there is an important role for new tools that can estimate the geometry, for use in accident research and in other applications that depend on two- or three-dimensional visualization without on-site surveying. This paper describes methods for estimating horizontal and vertical curvature from digital data sources and the development of a geographical information system (GIS) application that can link accident data to the alignment. It is anticipated that such an application will provide a platform for future research to improve the understanding of the relationships between accident frequency and highway geometry.
The structural characteristics of manhole installations in pavements
S. F. Brown, C. J. Brown
Proceedings of the Institution of Civil Engineers, Transport, 135, 1999, November, 201–208
The existence of a manhole installation in a pavement represents a structural discontinuity because of the different characteristics of the pavement and the manhole chamber construction. This partly explains the high incidence of premature failure in the asphalt surfacing around these installations. This is considered to be caused by the larger vertical stiffness of the manhole, which results in a potentially damaging combination of stresses in the asphalt surfacing under wheel loading as it bridges the interface between the pavement and the manhole construction. Carefully monitored field observations revealed that the pavement material around a manhole can fail within a few months of installation. Consequently, field experiments were carried out to study the in situ behaviour of manholes and the immediately surrounding pavement. These experiments involved the use of a falling-weight deflectometer to test several in-service manholes. In addition, theoretical analysis was used to provide some preliminary guidance as to how improved designs may be evolved to provide longer lives.
Using in-car feedback to influence travel decisions
I. T. Byrne, M. M. O'Mahony, B. M. Broderick, W. D. E. O'sullivan
Proceedings of the Institution of Civil Engineers, Transport, 135, 1999, November, 209–216
It is widely accepted that there is a need to reduce private car use, thereby alleviating congested urban areas and reducing fuel consumption and emissions from transport vehicles. This paper examines one approach to achieving this aim, based on the hypothesis that car owners do not correctly perceive the full cost of a car trip. The primary objective of the research was to assess the potential for correcting this misperception through the use of a digital car running-cost meter, installed on the dashboard of a car, which displays on a real-time basis the cost of each trip. Cost meter information on marginal trip cost, external cost and the effect of driving style was provided to a sample of drivers in a small pilot action in Dublin. The findings from the data (diaries and interviews) are presented and extrapolated by means of a transport network model to assess potential energy savings. The key findings from the work are as follows.
There was a significant reduction in off-peak-period trips observed as a result of the car meter but there was no significant reduction in time spent in the car, distance travelled by car and the cost of driving.
A surprising finding from the project was that 40% of the subjects who happened to be changing their vehicle shortly after being involved in the project chose more fuel-efficient vehicles. They attributed their choice in part to their increased awareness of fuel costs as a result of their involvement in the project.
