VTI arrangerade Transportforum 13–14 januari 2021. En konferens som är störst i sitt slag i Norden och som 2021 hölls digitalt. Den innehöll ett 20-tal sessioner med en stor variation mellan olika ämnen. Temat för 2021 års inledande session var Coronakrisens påverkan på staden.

As water serves as a necessary and often irreplaceable input in a range of goods and services, a disruption in water supply can cause lost production and sales for businesses. Thus, large benefits may be generated by reducing the risk of water disruptions. To enable selection of economically viable risk mitigation measures, the investment costs should be weighed against the benefits of risk mitigation. Consequently, quantitative estimates of the consequences of disruptions need to be available. However, despite the importance of water to businesses, the literature on their financial losses due to short and long-term water disruptions is still scarce. The aim of this paper is to estimate time-dependent water supply resiliency factors for economic sectors, i.e., a metric focusing on the level of output that businesses can uphold during a disruption, to contribute to better decision support for water supply planning and risk management. An online survey was used to gather data from 1405 companies in Sweden on consequences of complete and unplanned water supply outages. Results show that Food, beverage and tobacco manufacturing and Accommodation and food services are the two most severely affected sectors over all analyzed disruption durations.

This study estimates the marginal cost of using road infrastructure. Based on a large data set with information on sections of the road network, including age, pavement type, and traffic, a more disaggregate analysis of pavement life than that in the literature is facilitated. The analytical strategy enables identification of major differences in marginal costs across the road network. This establishes that the deterioration of the road quality can be attributed not only to heavy vehicles but also light vehicles such as passenger cars, a possible reason being the widespread use of studded tires in a country with regular freeze-thaw cycles. Due to the limited width of time windows of the dataset observations, no evidence could be found to support the notion that road deterioration is significantly influenced by time alone. © 2020 Elsevier Ltd

We analyze the differences between corner solution and survival models in estimating the marginal cost of track renewals. Both approaches describe the renewal process in intuitively similar ways but have several methodological distinctions. Using Swedish data for the 1999–2016 period, results suggest the median marginal costs per gross ton-km from corner solution and survival models are SEK 0.0066 and SEK 0.0031, respectively. Since several European countries use information about marginal costs as a basis for track user charges, the choice of estimation method is obviously important. Our conclusion is that the corner solution model is more appropriate in this case, as this method considers the impact traffic has both on the probability of renewal and on the size of the renewal cost. The survival approach does not consider the latter as part of the estimations, which is problematic when we have systematic cost variations due to traffic and infrastructure characteristics.

VTI arrangerade Transportforum 9–10 januari 2019 i Linköping Konsert & Kongress. En konferens, som är störst i sitt slag i Norden och som 2019 innehöll 90 sessioner med en stor variation mellan ämnen. Temat för 2019 års inledande session var elektrifiering – möjligheter och utmaningar att nå klimatmålen.