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The negative impacts of urban traffic growth are well known, e.g., congestion, increased air pollution, and more traffic noise. Humans can readily see traffic congestion, and can hear traffic noise, but inevitably they are much less aware of odorless, invisible, silent air pollution. Therefore, quite naturally people, whether the general public or transport professionals, struggle to visualize air pollution from traffic, and will find it particularly difficult to visualize changes in air pollution levels resulting from changes in traffic conditions because of the implementation of various urban transport schemes. Hence, there is always a risk of the air quality impacts of potential urban transport schemes being underappreciated. Therefore, this paper contributes to the knowledge by devising a new three-dimensional (3D) visualization approach for modeled air quality before and after the implementation of potential urban transport schemes. Using the Dunkirk area of the City of Nottingham in the United Kingdom as a case study, research has been undertaken to integrate an air pollution dispersion model for the pollutant with a 3D digital city model. The modeled concentrations, before and after the implementation of an urban transport scheme, were represented in the 3D city model at various heights above the ground: first, as 3D point shapes; second, as 3D planar surfaces; and finally, as 3D volumetric clouds. The 3D volumetric clouds approach used the analogy of people's perceptions of gray clouds in the sky as representing undesirable weather, and hence provided an intuitive 3D visualization of all the modeled concentrations, at and above the ground surface, in a single 3D virtual scene. Benefits have been identified in enhancing the level of understanding of the pollution dispersion using this new approach to visualization. This has allowed the visualization process to be used in the development of future traffic scenarios that could be used to alter the design of a proposed transport scheme to increase its air quality benefits. This 3D visualization approach was found to be applicable to other transport schemes in different parts of the City of Nottingham. [ABSTRACT FROM AUTHOR]

This work focuses on the coupling of a validated source model for free field traffic-induced vibrations to a receiver model that enables one to predict the response of buildings, accounting for dynamic soil-structure interaction. The resulting model is validated by means of in situ measurements, that have been performed in and around a single-family dwelling during the passage of a truck with known characteristics at speeds between 23 km/h and 58 km/h on joints between plates of the concrete pavement and on a plywood unevenness installed on the road. Simultaneous vibration measurements have been performed with a mobile data acquisition system on the truck's axles. The objective of part I of this paper is to present the validation of the source model. The characteristics of the vehicle and the road unevenness are discussed, and the vehicle response is validated. The response is independent of the vehicle speed for the passage on the joints, whereas, for the passage on the plywood unevenness, the vibrations increase with the vehicle speed. The dynamic road-soil interaction problem is subsequently solved. Special consideration is given to the determination of the dynamic soil characteristics using the spectral analysis surface wave and seismic cone penetration test methods and to the validation of the transfer functions in the soil. The free-field incident wave field is finally validated. This incident wave field is used in part II of the paper to predict and validate the response of the single family dwelling. [ABSTRACT FROM AUTHOR]