The new concept of virtual coupling (VC) envisages autonomous trains running in radio-connected platoons to significantly improve railway capacity and address the forecasted increase in railway demand. Such a concept will introduce radical changes to current train services, technologies, and procedures, which calls for a deeper understanding of the possible modes of operation and the impacts on the entire railway business. This paper investigates market potentials and operational scenarios of VC for different segments of the railway market: high-speed, main-line, regional, urban, and freight trains. The research builds on the Delphi method, with an extensive survey to collect expert opinions about benefits and challenges of VC as well as stated travel preferences in futuristic VC applications. Survey outcomes show that VC train operations can be very attractive to customers of the high-speed, main-line, and regional market segments, with benefits that are especially relevant for freight railways. In particular, customers of regional and freight railways are observed to be unsatisfied with current train services and willing to pay higher fares to avail of a more frequent and flexible service enabled by VC. Operational scenarios for VC are then defined by setting market-attractive service headways and by characteristics of the rolling stock, infrastructure, and traffic management. An analysis of strengths and weaknesses of such a concept together with business opportunities and threats is carried out. The defined VC future scenario is set to induce a sustainable shift of customers from other travel modes to the railways.

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Hydroplaning and the corresponding hydroplaning speed of a vehicle are critical road safety concerns. To avoid hydroplaning, nine technical measures are available. One of the most effective is the construction of skew superelevation runoff at the critical pavement section of a highway, especially in highway rehabilitation and reconstruction projects. The concept was introduced in the German RAS-L design guide of 1984; its implementation is found mainly in central European countries. Skew superelevation runoff was adopted in recent freeway projects, some of which are reconstructions of existing two-lane highways into freeways to address identified sections with high potential for hydroplaning. Its use under normal traffic has resulted in concerns about its safety and comfort effectiveness. To investigate the operational and safety performance of the constructed skew superelevation runoffs, accurate triaxial acceleration measurements were carried out on the Korinthos-Patra freeway in Greece for a combination of vehicles and speeds along these skew superelevation runoff sections. Resulting limitational thresholds were shown to be adequate for safe operation of the skew superelevation runoff. Vehicle occupant comfort thresholds, however, are narrow and require specific additional construction improvements when design values are not observed.

Virtual Coupling (VC) is a newly introduced concept of train-centric signalling technology that conceives trains to run autonomously in radio-connected platoons. These trains move synchronously at a relative braking distance to significantly improve railway capacity and address the forecasted increase in railway demand. The technical feasibility of VC depends on its strengths, weaknesses, opportunities and threats which can introduce radical changes to current train services, technologies and procedures. This paper investigates demand trends and operational scenarios of future train-centric signalling systems. To this end, stated travel preferences have been collected by means of a survey to have more insight on modal shares in the case of future VC applications. In addition, a Delphi method has been applied where another extensive survey has collected expert opinions about benefits and challenges of VC. Results show that VC can be very attractive to customers of high-speed and main line railways and have special benefits to the regional market where a manifest willing to pay more for using a more frequent train service was found. This concept therefore calls for a deeper understanding of possible Virtual Coupling operational scenarios and the impact on the railway industry.

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