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Because motor vehicle crashes have decreased during the last decade in many countries in the world and are more diffuse, local authorities have difficulties to define road safety policies. An experiment with 51 cars of public fleets equipped with a specific Event Data Recorder was carried out in France during one year. The purposes of this research were to evaluate if incident data (critical driving situations) help to understand crashes, and to explore a new way for road infrastructure safety diagnosis. The analysis of 339 genuine incidents and 1237 simple events recorded illustrates the potentiality of such an experiment and provides: some insights about conditions in which incidents occur, a general overview of their distribution according to different road layouts, as well as information on the different levels of accelerations reached. It can be noticed that there is an overrepresentation of incidents in right curves compared to left curves. The simple events involving mostly the infrastructure could be used to detect road defects. Genuine incidents where the vehicle is subjected to important dynamic demands, related to potentially unsafe driving situations, can be used to improve knowledge of the motor vehicle crashes thanks to incident mechanisms analysis.

Visibility level is a standard quality index in road lighting design. Three photometric values are needed to compute the visibility level of a target: its luminance, the luminance of its near background and the adaptation luminance. We discuss the consequences of how these parameters are set on the ability to predict the performance of a driver at target detection. An experiment was designed using a closed-road circuit. Sixteen targets were presented twice to 34 subjects. Six visibility level assessment methods were compared. The background luminance was set as the luminance at the bottom of the target, as the mean luminance around the target, or as the luminance associated with the maximum target contrast. The adaptation luminance was set either to the background luminance or to the mean luminance. The best non-linear fit between computed visibility level and target detection performance was found using the maximum contrast over the four sides of the square target, and setting the adaptation luminance to a unique estimated road luminance instead of the local background luminance. Even so, the variability of the visibility level data suggests great caution when using it as an index of road visibility.

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Porches or pull tubes are typically used as conventional hang-off systems for catenary risers suspended from spars. The Hybrid Catenary Riser (HCR) is a novel hang-off alternative to suspend risers from spars where conventional hang-off systems are not available. The HCR consists of a section of flexible pipe suspended from the spar deck and running down to a location about 120 ft below the keel, where it is connected to regular Steel Catenary Riser (SCR) pipe. The flexible pipe passes through intermediate guides in the spar structure, a receptacle protruding from the spar keel, a curved guide pipe attached to the receptacle, and exits a bend stiffener attached to the curved pipe. The curved guide pipe controls the riser departure angle. During pull-in, a bend stiffener connector (BSC) will lock the bend stiffener to the curved pipe while the flexible pipe slides freely through the bend stiffener allowing the pipe to be pulled up to the spar deck. Feasibility of the HCR configuration is verified through state-of-the-art computer modeling. Installation procedures are developed to demonstrate installability. This paper presents the concept in detail and identifies its technical and economic advantages.