The municipal street network acts as a multifunctional asset by providing people, vehicles and public services with a well-functioning infrastructure. To keep it in good condition, optimal maintenance measures are required which would result in an efficient use of taxpayers' money. This paper investigates the street network deterioration processes and the management practices that the municipal administrations have applied in Sweden. The study is based on a survey with Swedish municipalities using questionnaires and complementary interviews. The answers provide insight into a wide range of common pavement distresses and deterioration factors, along with pavement management practices. The study identifies that potholes, surface unevenness and alligator cracking are the most cited challenges, while pavement ageing, heavy traffic and patches are the most noted causes. Similarly, the cold climate and population density are influential factors in pavement deterioration. Allocation of the maintenance and rehabilitation and reconstruction budget is higher in the northern part of the country as well as in densely populated municipalities. Condition data collection and use of commercial Pavement Management Systems (PMS) are limited. Addressing the challenges effectively may be possible through the enhancement of the budget, feasible/clear guidelines from municipal councils/politicians, and reducing the gap between street network administrations and utility service providers.

New simulator models concerning vibration, noise and graphics have been designed and implemented in the VTI Simulator III. The objective of this study is to validate this simulator in terms of road surface realism. Twenty-four drivers participated in the study and drove the same route both in the simulator and on real roads. Three road sections ranging from very smooth to rather uneven were incorporated in the design. The comparison included the objective driving parameter speed as well as subjective parameters from questionnaires and rating scales (evenness, quietness and comfort level). A road section with five speed limit changes was of particular interest in the analyses. No statistically significant difference could be found between the simulator and the car, neither in the parameter speed (in sections with no speed limit changes) nor in the ratings evenness and quietness. Despite similar speed profiles surrounding the speed limit signs, there was a statistically significant difference between the speed in the car and in the simulator, with more rapid accelerations and decelerations in the simulator. The comfort rating was shown to be higher in the car compared to the simulator, but in both cases the general trend showed higher comfort on smoother roads. These results indicate absolute validity for the ratings evenness and quietness, and for the measure speed, and relative validity for comfort and speed surrounding speed limit signs.

Laboratory and filed investigations have been carried out to evaluate the performance of rubber modified asphalt test road on E22 Mönsterås.

The laboratory investigations indicated that there are no significant differences in stiffness and shear modulus between the reference and rubber modified mixtures. The rubber modified mixture however showed slightly lower phase angle compared to the reference mixture which indicate that the rubber modified mixture is more elastic. The rubber modified mixtures also showed lower modulus at lower temperatures and slightly higher modulus at higher temperature which are desired properties for resistance against low temperature cracking and permanent deformation respectively. The fatigue tests indicated that the rubber modified asphalt mixture has slightly better fatigue cracking performance. But the difference is not significant.

The road surface profile measurements indicated no significant differences between the reference and asphalt rubber sections. It is however early to draw conclusions after one year of traffic therefore additional follow-up of the test sections is needed to draw a conclusion.

Det projekt som här rapporteras har som syfte att identifiera och beskriva de svårigheter och möjligheter som totalentreprenader medför, respektive erbjuder, för alla parter. Målet är att utveckla totalentreprenader på ett sådant sätt att branschens effektivitet ökas. Denna rapport är en förstudie där det studerats vilka krav som byggherren ska ställa på utföraren av en vägkonstruktion i en totalentreprenad med funktionsansvar och hur utföraren ska verifiera kraven. Arbetet har genomförts med medlemmar från olika aktörer i branschen och omfattat främst litteraturstudier och intervjuer. Kunskaper och erfarenheter har sammanställts och analyserats för att slutligen kondenseras ned till ett antal förslag till fortsatt arbete.

Förstudien har pekat ut ett antal områden som viktiga för att påskynda framtida utveckling av totalentreprenader:

Terminologi – idag råder viss begreppsförvirring

Analys av funktionella krav i tidigare projekt

Trafikantkrav

Miljökrav

Utveckling av funktionella krav i samverkan

Väghållarekonomi

Regelbetingade begränsningar av funktionella krav

Uppföljning och underlättande av erfarenhetsackumulering

Implementering av nya mått och mätmetoder

Vissa tillsatsmedel upplevs idag som besvärliga för arbetsmiljön vid tillverkning och utläggning av asfaltmassa. Vidstående projekt som finansierats av SBUF och Peab Asfalt AB syftar till att ta fram relevanta fakta om tillsatsmedel och dess hälso- och miljöproblem. Projektet har dels inriktats som en förstudie av vad som hitintills har gjorts inom asfaltmiljöområdet både i Sverige och i utlandet, dels kompletterande fältmätningar vid asfaltläggning av polymermodifierad asfalt. Studien har utförts i samarbete mellan Peab Asfalt AB, VTI och Previa/ARA-miljö.

In collaboration with Hövding, data has been collected to highlight how different aspects can explain events where the helmet is deployed. The helmet records accelerations, and when a helmet is deployed, this information is sent to Hövding. They then invited the cyclist to participate in a web- survey and an interview. Thus, to increase our understanding of why bicycle accidents occur, data have been collected from the helmets, from a web-survey and from interviews. A total of 196 participants completed the web-survey while 50 participants were interviewed. In addition, data from the helmets were collected from 355 cyclists, of which 264 have had the helmet deployed.

One main result is that it is on an ordinary day, during an ordinary journey to or from work, by experienced cyclists that are highly educated. Cyclist were aware of traffic rules and what is happening around them – when "it suddenly happens" and it is not until then the cyclists realize how vulnerable they are. The study shows how a complex pattern emerge from the data sources used to understand why a bicycle accident actually occurs. For example, slippery conditions increase the risk of an event, and if "slippery" is combined with darkness the risk increases even further. The data from the helmets could confirm the results from the web-survey and the interviews, but also demonstrate that the helmet, on journeys which ended with the helmet being deployed, had higher levels of activation compared to journeys where it was not deployed. Furthermore, on trips made after the deployment, the helmet also had lower levels of activation which can be understood as the cyclists adapting their behaviour by, for example, cycling more carefully (but not slower). Finally, the results show differences between conventional and electric bicycles in terms of involvement in events where Hövding was deployed.

Background

In collaboration with a bicycle airbag helmet company, data were collected to help explain events where head protections are deployed. The head protection records activations continuously, and when a head protection is deployed, this information is sent to the company. The company invited affected cyclists to (i) participate in a web survey, and (ii) share their data with researchers. The first aim of the study was to investigate the proportions between different severities of crashes, i.e., how many crashes with serious injuries occur for every crash with minor injuries, while the second aim was to predict when bicycle crashes will occur.

Method

A total of 196 cyclists completed the web survey. Participants were 20–76 years old (mean age 46 years) and consisted of 125 women and 55 men. The cyclists were highly educated, and 73 percent had completed a university or college education. In addition, head protection data were collected from 355 other cyclists, of which 264 had their helmet deployed.

Results

One of the 182 (included events) cyclists ended up in hospital care. The data collected indicated the proportions of cyclists who needed hospital care (1 = severe injuries), cyclists with injuries (15), slight injures (85) and cyclists who could continue as before (81 = no injuries). The head protection data confirmed the web survey findings, but also demonstrated that the head protection, on journeys that ended with head protection deployment, had a higher degree of activations before the event) compared to journeys where it was not deployed. Furthermore, on trips made after deployment, the head protection had lower levels of activations, which can be understood as the cyclists adapting their behavior by, for example, riding more carefully (but not slower).

Conclusion

This study highlights the proportions of events leading to minor injuries versus hospitalization. Activation measures (head protection conditions) can predict when events will occur, and cyclists will adjust their behavior accordingly following events.

To fulfil the global sustainable development goals (SDGs), achieving sustainable development is becoming urgent, not least in the transportation sector. In response to this, the sustainability framework Sustainability National Road Administrations (SUNRA) was developed to contribute to improving the sustainability performance of national road administrations across Europe. In the present study, the framework has been tested, applied and further developed to be applicable for target setting and follow-up at the project level at both the Swedish Transport Administration (STA) and at municipal levels. The aim was a framework relevant for investment, re-investments, maintenance and operation projects and also to make it more user applicable. The study also investigated how the framework can contribute to sustainability, identified drivers and barriers for applying the framework and examined whether the framework can be applied and adapted to projects of different complexities. The adaptations and developments were done in collaboration between researchers and practitioners. The results show that the framework could easily be used and adapted for investment, re-investment, maintenance and operation projects in the planning stage, as well as for small municipal establishments, construction or reconstruction of residential areas and frequent maintenance. The framework contributes to increased awareness on sustainability, and it provides a common structure and transparency on how infrastructure project goals/targets are set and fulfilled. The framework can also be applied to follow the fulfilment of the goals/targets and thereby adapt the project to better fulfil the goals. Identified barriers include the lack of obligations and lack of experience in using sustainability frameworks.

Coal tar was used in Sweden for the production of asphalt and for the drenching of stabilization gravel until 1973. The tar has high concentrations of polycyclic aromatic hydrocarbons (PAH), some of which may be strongly carcinogenic. Approximately 20 million tonnes of tar-containing asphalt is present in the public roads in Sweden. Used asphalt from rebuilding can be classified as hazardous waste according to the Swedish Waste Act. The cost of treating the material removed as hazardous waste can be very high due to the large amount that has to be treated, and the total environmental benefit is unclear. The transport of used asphalt to landfill or combustion will affect other environmental targets. The present project, based on three case studies of road projects in Sweden, evaluates the consequences of four scenarios for handling the material: reuse, landfill, biological treatment, and incineration. The results show that reuse of the coal tar-containing materials in new road construction is the most favorable alternative in terms of cost, material use, land use, energy consumption, and air emissions.

Even if the greenhouse gas emissions are rapidly reduced, the ongoing climate change will result in extensive and costly climate-related events that will occur more frequently. The costs in the Swedish transport sector for such events damaging streets, roads, rail/railways, and other vulnerable parts of the infrastructure are high today and are expected to increase. The consequences of weather-related events are, among other things, reduced accessibility, and increased risk of accidents. To maintain the functioning of the transport system, it is important to undertake risk-reducing measures related both to today's climate, but above all, to manage future climate-related events. It is necessary to ensure the functioning of the transport system during extreme weather events, and during periods of prolonged precipitation, prolonged heatwaves and changing precipitation patterns. It is also important to enable adaptation measures to deal with long-term changes such as rising sea levels which affect the accessibility and lifespan of the infrastructure.

This report presents a summary of results and a summary of how a framework for evaluating climaterelated impact relationships has been used. Effect relationships refer to identifying, assessing, and evaluating climate-related risks and risk reduction measures. In this report, the focus is on identifying, assessing, and evaluating the effectiveness of climate-related measures. The results is a framework for assessing the effect of risk-reducing measures, i.e., to assess whether it is relevant to implement a measure, when in time it should be implemented and to assess which measure is most relevant to implement. The risks have considered in case studies and include fire risk, risk of accidents on streets and roads due to zero crossings or heat, flooding, erosion and landslides and impact on road construction (rutting, bearing capacity and fatigue), track buckling and risks related to high winds. The tests have included hazard and risk identification, risk analysis, identification, and evaluation of possible measures. Examples of case studies are a torrential rain in Kungsbacka municipality in 2019, erosion-related changes over a long period of time at Österdalälven and calculations of climate impact on the road construction at the E10 at Svappavaara. A case study has also included monetary valuation and sensitivity analysis. The framework has also formed the basis for a discussion regarding climaterelated risks linked to electricity supply.

SUNRA (Sustainability: National Road Administration) SUNRA is a decision support tool developed to be used in road projects by setting the level of ambition for different sustainability aspects and following up the work towards these in a structured way. 

This memo describes how to use SUNRA, followed by a chapter with suggestions on where in the planning process SUNRA can be used, followed by chapters presenting the themes and aspects that are considered within SUNRA and the underlying issues that constitute the result of the updates made in this version. 

In this version, SUNRA has also been sued against the global sustainability goals as well as the Swedish Transport Administration's interpretation of them in Målbild 2030. SUNRQ aims to use it to contribute to sustainable development with a higher level of ambition than just the legal requirements and other criteria that need to be taken into account. Therefore, for the aspects taken into account, minimum requirements for objectives are the legal requirements that exist and the Swedish Transport Administration's own objectives and policies

Severe accidents and high costs associated with weather-related events already occur in today’s climate. Unless preventive measures are taken, the costs are expected to increase in future due to ongoing climate change. However, the risk reduction measures are costly as well and may result in unwanted impacts. Therefore, it is important to identify, assess and prioritize which measures are necessary to undertake, as well as where and when these are to be undertaken. To be able to make such evaluations, robust (scientifically based), transparent and systematic assessments and valuations are required. This article describes a framework to assess the cause-and-effect relationships and how to estimate the costs and benefits as a basis to assess and prioritize measures for climate adaptation of roads and railways. The framework includes hazard identification, risk analysis and risk assessment, identification, monetary and non-monetary evaluation of possible risk reduction measures and a step regarding distribution-, goal-and sensitivity analyses. The results from applying the framework shall be used to prioritize among potential risk reduction measures as well as when to undertake them.

Sunra (Sustainability: National Road Administration) Sunra is the Swedish Transport Administration’s (STA) decision support tool developed to be used in road projects by setting the level of ambition for different sustainability aspects and following up the work towards these in a structured way. 

This memo describes how to use Sunra, followed by a chapter with suggestions on where in the planning process Sunra can be used, followed by chapters presenting the themes and aspects that are considered within Sunra and the underlying issues that constitute the result of the updates made in this version. 

In this version, Sunra has also been sued against the global sustainability goals as well as the Swedish Transport Administration's interpretation of them in Målbild 2030. SUNRQ aims to use it to contribute to sustainable development with a higher level of ambition than just the legal requirements and other criteria that need to be taken into account. Therefore, for the aspects taken into account, minimum requirements for objectives are the legal requirements that exist and the Swedish Transport Administration's own objectives and policies 

This memo is a compilation of the adaptation and update work made by Sunra version 2018-12-152 within the framework of sub-project 1.12 Sustainable analysis for smart maintenance in the program Mistra Inframaint. The update has been made to enable Sunra to be used both within investment, operation and maintenance projects. Updates have been made with respect to the aspects that are taken into account within the different Themes, within which Themes different aspects are taken into account and to match ongoing working methods within Investment and Operation and Maintenance at the Swedish Transport Administration. In the work on the update, exports from Operation and Maintenance and Investment have been involved.

Sunra (Sustainability: National Road Administration) is a decision support tool developed to be used in road projects by setting the level of ambition for different sustainability aspects and following up the work towards these in a structured way. 

This memo describes the results of continued development of Sunra adapted for local and regional infrastructure. The result is the prototypes Sulri (Sustainability Local and Regional Infrastructure) and Sulri-frequent. Sulri-frequent is intended to be used for more frequent projects, such as paving existing streets, and Sulri is intended for projects that are a little more complex such as rethinking or replanning such as improving for active travel, climate adaptation of an area or adapting a street, a place or an area to other needs, but Sulri can in principle also be used for more frequent or smaller projects. This report describes a first version of Sulri. The report shows how the tool should be used. Chapter 3 then presents the themes and aspects that are considered within Sulri. Appendix 2 gives the corresponding information for Sulri-frequent. Appendix 1 presents relevant documents and links for the different themes and aspects considered in Sulri.

This report presents the results of a feasibility study aimed at developing a methodology to support the transport Agency's planning of climate adaptation measures. The report focuses on the effect relationships for the identification, assessment and prioritization of measures for climate adaptation of roads and railways. The results presented in this report are based on literature studies and interviews with road and rail experts.

The report takes into account the consequences and risks that are expected to arise from climate-related events, such as the impact that arises from a heavy rainfall and measures that can be taken to reduce the risk and the effect thereof. Knowledge of the likelihood of a particular climate-related event occurring during a given period, as well as the size and type of injury, is required to assess or calculate the risk. The cost of damages is for example the delay costs, and costs of transfer and changes between modes of transport, etc., and recovery costs and injuries to humans.

In Sweden, longitudinal roughness has been more or less synonymous with the International Roughness Index (IRI). IRI is calculated from a longitudinal profile, and describes the accumulated movement between the wheel and chassis on a quarter-car model. The result is given as this movement divided with the traveled length. In Sweden, the unit millimeters per mere is normally used. The IRI-model is only affected by movements in the vertical direction, and the speed is fixed to 80 km/h. This report presents the work to make a full-car model, with the aim to produce a more realistic view of the movements of a vehicle traveling on a normal road. The benefits with a more realistic vehicle model is that indices with a higher correlation to drivers’ and passengers’ experiences can be made. It should be mentioned that a relatively high correlation between IRI and drivers’ estimates road condition has been shown. A FullCar model should, however, give more detailed information about the effect of the road surface on the vehicle. A truck model could, for example, be used to find sections with a dangerous cross fall. A realistic vehicle model could also be used in studies concerning the deterioration of roads, as the road is partly worn by wheel abrasions and partly deformed by contact forces. A simple model could simulate hundreds of thousands of vehicle passages in only a few minutes.

Trafikverket upphandlar numera ofta vägar på totalentreprenad med funktionskrav där en huvudsaklig kravställning görs på tvärgående jämnhet (spårdjup). Denna kontraktstyp kan innebära relativt stora risker för entreprenörer eftersom man redan i anbudsskedet behöver kunna bedöma kostnader för felavhjälpande och underhållskostnader senare under garantitiden. För att kunna bedöma framtida underhållskostnader vid denna typ av kravställning behövs modeller som kan prognostisera spårdjupsutvecklingen. Sådan prognostisering kan antingen ske på olika sätt, t.ex. på övergripande nivå, inte sällan med manuell beräkning i populära kalkylprogram (t.ex. excel), baserat på olika nyckeltal från en eller flera vägar. Ett annat sätt, och som detta projekt utgår från är att på relativt detaljerad nivå utnyttja succesiva data från den aktuella entreprenaden, som skall prognostiseras, vilket kräver årlig data av hög kvalitet, d.v.s. data som filtrerats från förmodade felaktigheter och synkroniserats såväl geografiskt som kronologiskt. Detta projekt har syftat till att utveckla och utvärdera ett sådant verktyg. Denna rapport går igenom utvecklingsprocessen av verktyget och hur man använder det samt förklarar dess uppbyggnad för de huvudsakliga delarna tillsammans med exempelkod i syfte att möjliggöra för aktörer som önskar implementera liknande varianter

In Sweden, the road surface condition is assessed regularly with laser-based profilographs. This has been done since 1987. All roads are, for financial reasons, not assessed every year, but one way to describe the condition of the entire road network is to work with models. The purpose of these assessments is to provide the Swedish Transport Administration’s Pavement Management System (PMS) with data. The main uses of the PMS are: • To provide a description of the overall road condition and its changes to determine if the selected operation and maintenance strategies are successful, and if an acceptable road standard can be offered. • Support the maintenance planning (prioritization and selection of sections for maintenance). • Support for the choice of maintenance method. • Monitoring of performance of construction or maintenance, for example, functional related contracts. • To support research. The Swedish Transport Administration needs a complete description of the road condition in order to demonstrate to the government and parliament how the mission to maintain the roads is achieved. One way to describe the condition of the entire road network is to work with models that forecast the condition the years when measurements are missing. In the choice between using a global or local model to describe the state of development for IRI (International Roughness Index) and rut depth on individual 100-meter segments, the present report shows that a local model is preferred. The coefficient of determination is not high enough in a global model. Also, the researchers cannot see any consequent pattern in the regression coefficients for the explanatory variables we have tried.

Objective: The study examines how drivers experience a conventional W-beam guardrail (metal crash barrier) along both sides of narrow versus wider roads (single carriageway with 2 lanes) in terms of stress, feelings, and driving patterns and whether subjective experience concurs with the actual driving patterns captured by the quantitative data.

Methods: The study used different methods to capture data, including the VTI Driving Simulator III (speed and lateral vehicle position) in conjunction with electrocardiogram (ECG) data on heart rate variability (HRV) and questionnaires (oral during driving and written after driving). Eighteen participants-8 men and 10 women-were recruited for the simulator study and the simulator road section was 10 km long.

Results: Driving speeds increased slightly on the wider road and on the road with a crash barrier, and the lateral driving position was nearer to the road center on the narrower road and on the road with a crash barrier. The HRV data did not indicate that participants experienced greater stress due to road width or due to the presence of a crash barrier. Participant experience captured in the oral questionnaires suggested that road width did not affect driver stress or driving patterns; however, the written questionnaire results supported the simulator data, indicating that a wider road led to increased speed. None of the participants felt that crash barriers made them feel calmer.

Conclusions: We believe that there is a possibility that the increased speed on roads with crash barriers may be explained by drivers’ sense of increased security. This study demonstrates that an experimental design including experience-based data captured using both a simulator and questionnaires is productive. It also demonstrates that driving simulators can be used to study road features such as crash barriers. It seems more than likely that features such as street lamps, signs, and landscape objects could be tested in this way. © 2013 Copyright Taylor and Francis Group, LLC.

The overall aim of this work is to develop guidelines for evaluation of potential treatments, categorized as “self-explaining treatments” by the use of a driving simulator. More specific the driving simulator study had the aim:

• • To evaluate the effectiveness of curve treatments, in particular to determine whether a combination of treatments on curves according to their severity could help drivers correctly establish the severity of a curve in advance, and therefore adapt their speed appropriately.

In total 35 participants, divided into two groups, drove approximately 46 minutes on a rural road with 3 baseline curves without treatment and 9 curves with treatment of varying levels. In total three different treatment levels and three different curves were used. One group received treatments before each curve that correspond to the severity of the curve (slight curve – low treatment level; moderate curve – medium treatment level; severe curve – high treatment level); the other group experienced inconsistent treatments by being exposed to all nine possible combination of curve and treatments.

The analysis of the effects on speed in average and at each point (v0 to v5) was done with Mixed Model ANOVA. Dependent variables were speed measurements in the different points along the curve (v0 to v5) and the average speed through the total curve (from point v0 to v5). The analyses were done both for absolute speeds and for the relative change in speed from starting point (v0). Independent variables were consistent/inconsistent group; curve (1-3), treatment level (1–3) and time on task, here called order (1–9). Subject was used as random and nested on group. In addition the most severe curve was analysed separately in order to compare the groups.

In conclusion the result showed that in most cases there were significant effects for treatment levels, severity of the curve, order (time on task), and for subject. There was no significant main effect on group (consistent/inconsistent). However, there was an interaction between curve and group, telling us that the consistent marking significantly reduced the average speed among those with consistent treatment. This holds true also for the speed at point v2, v3 and v5. A final argument for the effectiveness of consistent treatment is that if only the severe curve was considered, there was a significant effect of group.

Guidelines for evaluation

It was found that our used method to evaluate the effects of speed adjustment worked well. 35 participants each drove approximately 45 minutes. They were divided into a consistent and one inconsistent group. Three levels of treatment and three severities of curves were used. The dependent variable was the speed measured at three points along the curve. This methodology could be used to evaluate other types of self-explaining treatments. But since a driving simulator study requires a lot of planning (expensive) it is suggested to initially do an expert workshop to evaluate and select the suitable SER treatment and also detailed scenario description.

Since injured pedestrians due to falling contributes to high costs for society, therefore the attribute requirements on a road surface is of great importance for safety. The requirements shall be appropriate for all who are on the surface, this applies to both vehicles, cyclists and pedestrians. This report summarises recent accident studies and the prevailing rules regarding the construction of spaces for pedestrians.

In addition to these compilations an analysis is done of how common it is that people fall due to, for example, uneven surfaces, kerb-stones or stumble. In 38 percent of the reported accidents that occurred between 2008 and 2015 (82,559), the victims said that the accident happened on a footpath/pavement. To give a good picture of how many accidents that may occur due to surface and paving was 4,443 accidents filtered out, and all the descriptions were read and divided into 12 various categories. The most common reason to a person being injured, according to themselves, was unevenness, holes and pits, level differences or related to the stone/tile surface. The social-economic cost for these 4,443 accidents was in average 845 thousand SEK.

Road stretch forecasting is a method for forecasting the weather situations or road conditions, especially slipperiness. This project has been a start on implementing the road stretch forecasting technique on Swedish roads. Road stretch forecasting is already implemented in several parts of the world including Norway and the Czech Republic and is a method for forecasting the weather situations or road conditions on the stretches between the existing Road Weather Information System outstations (RWIS). RWIS outstations are located all over Sweden and mainly in places where there is a high probability of slipperiness. But if the area around the station is changed, for example modifications of the vegetation, the conditions can be changed compared to the original mapping of the road. This leads to a high probability for extreme points in road stretches in between the RWIS outstations. To make a model that describes the road, it is necessary to make a thermal mapping and an analysis of the topoclimate to know the variations in temperature, altitude, shading etcetera, along the road. Then the road is divided into segments representing the different variations of the road. The model calculates the forecast for the road surface temperatures and road conditions, the modelled values are compared and adjusted with the measured temperatures from the thermal mapping. In conclusion, the results regarding this road stretch along E6 show good congruence between the modelled values and the measured temperatures.

One important question in winter road maintenance is: How can we make winter road maintenance more energy efficient? There are several factors that can affect how, when and where the winter road maintenance is performed.

A RWIS outstation (Road Weather Information System) measures the road weather on the road and close to the road, it measures many parameters, such as road surface temperature, air temperature, relative humidity, precipitation type and amount, wind speed and direction. Measured parameters together with weather forecasts make it possible to determine when and where the action is needed. Thereafter it is time to make a route planning to ensure that the correct action is done on the right place at the right time, and with the best suited equipment for the winter road maintenance.

Spreading of salt/sand could be more efficient by using different computer programs that calculate the needed amount. Also the location of the salt/sand storage affects the driving distances i.e. the fuel consumption.

One of the factors that account for the greatest uncertainty in terms of winter road maintenance is the weather. An area that has a need for more research is how future climate changes will affect the winter maintenance.

The project “Winter Model” started at the beginning of the 2000s. The idea was to try and predict consequences of different winter maintenance strategies so that socio-economic costs could be calculated. Using the Winter Model programme, developed during the project, it is now possible to calculate and validate the impact of different winter maintenance measures have on road users, road authorities and local communities. This report contains results of the first complete Winter Model calculations using existing conditions. The report also contains an account of further developments made in connection with this study within the Winter Model. In order to determine what effect changes to road classification standards have on socio-economic costs, the report includes seven comparisons of different application runs. Road classification standards determine how much snow should fall before an action is initiated and/or how long it should take until the action is completed.

The Winter Model has been developed within a project called The Winter Model. The aim of the project, which started in the early 2000s, was to assess social and economic consequences of different winter maintenance strategies for road users, road authorities and local communities. The aim of this study was to calculate the change in fuel consumption when the winter maintenance classification standard is lowered on the road i.e. response times and start criterion is increased. Within this project, the fuel consumption model was refined and can now take into account how fuel consumption is affected by the amount of water or snow in the ruts on the road. During the project, six scenario runs were carried out for a 100 km long road section located in Sweden’s central climatic zone. Weather data was obtained from the winter season 2006–2007. Winter maintenance classification standards, and traffic flow volumes were varied during the scenario runs. In one scenario run, the winter maintenance classification standard was lowered from Standard Class 1 to Standard Class 2. This increased the allowable time to carry out the maintenance action from 2 hours to 3 hours – applicable to a Standard Class 1 road, salted, and with a traffic volume of 16,000 vehicles. Comparisons indicate a 1,100 litre reduction in total fuel consumption and maintenance costs was reduced by 5%.

The project “Winter Model” started at the beginning of the 2000s. The idea was to try and predict the consequences of different winter maintenance strategies and to calculate the associated socio-economic costs. It is now possible to calculate and validate the impact that different winter maintenance measures have on road users, road authorities and local communities.

This paper contains results of the first complete Winter Model calculations using existing conditions. Comparisons with different road classification standards have been carried out in order to determine the effect they have on socio-economic costs. Road classification standards dictate how much snow should fall before a maintenance action is initiated and how long it should take until the action is completed. Socio-economic costs increased for all comparisons when reductions in the classification standard were applied. As an example of how costs can vary: the scenario is a salted road using a combined plough and salt spreader where the allowed time to complete the action is 4 h that is changed to an unsalted road with an allowed time to complete the action of 5 h. Both scenarios have an action start criteria of 2 cm deep snow, and an annual average daily traffic flow of 2000.

Comparison results show that the change from salted to unsalted road saves the most cost due to a reduction in salt use and required actions. However, the increased time to complete the action will result in slightly longer travel times and accident costs will increase by 24.2%. The extended action hour affect fuel consumption in a positive way, for example, consumption decreases slightly due to driving more often at lower speeds on unclear roads. By lowering the road classification standard like in this example, total socio-economic costs increased by 3.5%.

The project “Winter Model” started at the beginning of the 2000s. The idea was to try and predict the consequences of different winter maintenance strategies and to calculate the associated socio-economic costs. It is now possible to calculate and validate the impact that different winter maintenance measures have on road users, road authorities and local communities. This paper contains results of the first complete Winter Model calculations using existing conditions. Comparisons with different road classification standards have been carried out in order to determine the effect they have on socio-economic costs. Road classification standards dictate how much snow should fall before a maintenance action is initiated and how long it should take until the action is completed. Socio-economic costs increased for all comparisons when reductions in the classification standard were applied. Accident costs consistently accounted for the largest cost increases in all of the comparisons. Current climate change impact scenarios for northern Europe predict an increase in temperature and precipitation, especially during the winter seasons. Some attempts have been made to use the Winter Model for comparisons between different winters, for example variations in weather patterns. These attempts tried to calculate winter maintenance and socio-economic costs for future winter seasons.

This report is a compilation of the work done of recalculating the relations/connections for accident risks and their distribution on different winter road conditions in different climate zones. These accident risks are based on accidents having occurred between the years 2007 and 2017. In this project, an update of the accident assessments has been made according to ASEK 6.1 (analysis method and socioeconomic calculation values for the transport sector) Due to this change, the Swedish Transport Administration has changed the valuation of road traffic accidents with accident consequences according to Strada (Swedish Traffic Accident Data Acquisition), instead of consequences as reported by police reports. The new update of the Accident Model has updated accident risks, accident distributions and accident consequences and seems to be realistic and the program is working in a correct way.

Barrier separated roads and “2+1” type barrier separated roads have become more common as they have been proven to be safer than the conventional two-lane roads. Accident statistics show that there are fewer serious accidents. However, there are few studies on how winter road maintenance affects accessibility, accidents and environmental effects (energy consumption/emissions) when a barrier separated road is compared with the conventional two-way road. The Winter model has been developed by VTI for the Swedish Transport Administration over the past 20 years. It is built with sub-models and effect relationship for a two-lane road. Therefore, further development begun to include a 2+1-road to use the model on the entire state road network. Since only a few studies are made of traffic flows and speed measurements in separated lanes, relatively uncertain assumptions underlie the changes in road conditions on a 2+1-road in the model. It is important to be able to model changes of road conditions as close to reality as possible, in order to get the model as realistic as possible for calculating how changes in winter road conditions can affect the socio-economic costs during a winter season. A lane on a 2+1-road is usually narrower than the lane on the conventional road. It has been found in this study that in wintertime the drivers do not have the same driving pattern as on a bare road. As an example, during a snowfall on a road with standard class 1–3, the contractor should plough the road when 1 cm of snow has fallen. Then they have 2–4 hours to plough the route and when it has stopped snowing, the road should be snow- and ice-free within 2–4 hours if it is not colder than -6°C. This means that if there is enough snow to cover the road, the vehicles automatically appear to drive slightly further to the left in the right lane, probably not to risk getting into the ditch. It also leads to fewer overtakings. This may be due to a combination of the fact that most drivers are further to the left, making lane two narrower and when there are fewer vehicles in the left lane there is uncertainty about the road surface conditions and very few vehicles make an overtaking. This, in turn, means that the Winter model cannot really handle the roadway in the left lane as there are not enough road condition studies of snow depth. This project has contributed to more knowledge and some adjustments have been made that make the model more reliable. However, further studies on distribution, speed and lane placement of vehicles in various lanes during and after a snowfall are required.

VTI has developed a model called the Winter Model, a strategic tool to make calculations for the winter road maintenance during the whole winter season and how this affects the societies costs. This report contains a summary of other models used in this area. The report mostly contains brief explanations of some of the existing tactical decision support systems. No strategic models which is used as tools for follow-up on consequences depending on actions taken on the road, level of winter service, and on how a different winter seasons climate affects the economics, could be found. Most countries have developed their own tactical decision support system. These systems are in many cases very similar, and they are generally used for the decision of the best maintenance activity to perform. The model that reminds the most of the Swedish Winter Model is the American MDSS-model, which has approximately the same incoming data. The largest difference is that it is more used in the daily activities and not as a tool to make calculations for the winter road maintenance during the whole winter season and how this in turn affects the societies costs.

The global climate change is a reality and affecting society and transport systems. Climate change adaptation of transport systems will make the means of transportation more resilient and decrease the risk and magnitude of disruptions. Generally, climate change adaptations in road construction, operation and maintenance will need relatively large changes, but there is a shortage of the specific knowledge required as to what steps need to be taken, when and where, before measures can actually be implemented. Since climate change effects vary among Sweden's climatic zones, the impact of climate change on the road behavior and longevity is extremely difficult to predict. The need for winter maintenance in Sweden will generally decrease due to the warmer climate. Ploughing frequency will probably decrease as well, but preparedness should not be reduced too much since occasions with more extreme instances will increase. In order to succeed in making the road transport system resilient to climate change, we conclude that there is a need to develop more knowledge about the impact on the road infrastructure system as well as the operation and maintenance of the system including how to adapt through different types of variable and flexible climate adaptation measures and the effects of extreme weather events.

In a changing climate with greater demands on road managers and winter operation contractors to achieve a winter operating standard acceptable to road users while at the same time the financial resources become increasingly limited, the need for cost-effective methods increases. A forecast-driven dynamic road operation has been shown to lead to increased productivity as road condition forecasts are integrated with route optimisation. 

One way to further develop road conditions forecasts is to know how much salt is needed on the road, or more precisely, how much residual salt is still there? If there already is salt on the road, then is there no need to spread the full amount, it might be enough with half or even less. 

Residual salt measurements have been made during three winter seasons at Testsite E18. The site was chosen because it is equipped with several different sensors, mounted above, next to and in the road. Salt was measured every 30 cm across the road's two lanes. Of 9 measurements, there were only 5 occasions with salt, of which two of them were salted only for our measurements. There were three measurements left with winter conditions. All measurements were compared with sensors on the site to compare how well a sensor represents the road surface. It turned out that there were generally very low salt values from the sensors compared with manual measurements.

The future needs for winter maintenance will probably be influenced by the climate change in different ways in different parts of the world. As Sweden is a country with several climate zones, the influence of climate change on winter maintenance will therefore differ between regions within the country. To understand the influence of climate change on the future needs of salt consumption in winter maintenance, modeled road weather data were calculated in the IRWIN project (a joint research project through ERA-NET ROAD funded by the 6th Framework Program of the European Commission), where climate change scenarios from ECHAM5 (the fifth generation of the European Centre Hamburg Model general circulation model from the Max-Planck Institute for Meteorology) were combined with field data from the road weather information system in Sweden.

These modeled road weather data were used in project KLIVIN (the study presented here) in three Swedish regions (Gothenburg, Stockholm, and Sundsvall) and was combined with the Swedish winter severity index in order to calculate the trends of future salt needs. In this study the needs of salt for each of the three investigated regions were calculated in 30-year periods between 1970 and 2100. The results show that salt use related to snowfall will decrease in all three regions, while the salt use related to temperature will increase in the northernmost region (Sundsvall) and show a small decrease in the two other regions (Gothenburg and Stockholm).

Unpredictable weather, short time frames and requirements of high quality can make a challenge of the winter road maintenance. The pressure on both operating staff and machine drivers is very high during periods. The road climate can vary greatly within one and the same operating area and there is a need to adjust for these variations to maximise efficiency.

The project "Dynamic Forecast Controlled Winter Road Maintenance" has been aimed at developing a solution to simplify the handling of data flows from road weather forecasts and simplify decisions for the winter maintenance contractor what actions are needed and where they are needed. This has been done with data from road weather forecast services together with the existing road network in the operating area, the actions have been optimized for the available numbers of vehicles to create dynamic actions for a more productive and sustainable winter road maintenance.

Two phases of the project have now been completed and the purpose and goal of streamlining operations through interconnected data flows has been achieved. In connection with this, a dynamic forecasting route optimisation product has also been developed. The project showed that using a dynamic forecasting route optimisation, is it possible to carry out the full potential of the decision support systems through automation. The potential of using forecast-based winter road maintenance is great, both for the customers and for the individual operating contractor. The contractor benefits from it in the operational work, improves the working environment and reduces costs. However, environmental impact also decreases, and in the long term, it also reduces the social economic costs of road maintenance. It is important to emphasise that the technology enables the safety factor on the road to not be reduced despite savings of salt and action times.

Current winter maintenance costs are approximately 2 billion SEK per annum, but good monitoring tools to ensure that this money is distributed and used effectively are lacking. The purpose of this study was to develop a basis for new regulations for when action is required to maintain good winter road standards and how payment to the entrepreneurs should be regulated to provide a more efficient winter road maintenance. The Swedish Road Weather Information System (RWIS) was introduced as an aid for winter road maintenance in the late 1970s. The service expanded during the next two decades and today comprises of around 800 stations situated around the Swedish state road network. Measurements include air and road surface temperature, wind direction and speed, and precipitation type and amount. Many of the stations are also equipped with cameras that can be used to assess road surface conditions. Together with weather forecasts, information from RWIS stations is used as the main basis for decision making regarding the need for winter road maintenance. The first step in system improvement is to fully understand how the current system operates. This report summarises the broad outlines of how reporting, regulatory frameworks, and reimbursement models work for winter road maintenance. There are a number of relatively new techniques that could be used to optimise winter road maintenance. These new techniques could help produce a more efficient winter road maintenance programme that reduces the cost to society. The technological developments have moved forward in recent years in a number of areas such as the motor vehicle industry and also in non-contact sensors for measuring friction and road surface temperature. This technology can be used in conjunction with RWIS to give a clear indication of when and where maintenance action is required. This could also provide an opportunity to design a decision support system that could assist road maintenance contractors.

In the Nordic countries, winter road maintenance is important to deliver a safe and reliable road system. This also means that winter road maintenance has a relatively large share of the operating and maintenance budget for the Nordic countries. The developing projects in winter maintenance are therefore aimed both to deliver a high quality of winter service to the customersand that it is carried out in the most cost-effective way possible

The Nordic countries have ongoing projects through the managing process;plan, steering, follow up, inform, and describe the winter road maintenance. Development projects are also underway regarding the equipment for winter road maintenance, material properties and new methods for implementation to becomemore efficient and contribute to a lower environmental impact. Digitalisation offers new opportunities to work more systematically with the different parts of winter road maintenance from planning and control to follow-up. The Nordic countries have started projects to meet the new opportunities with digitalisation and to ensure that there is a high level of expertise in the profession.

In Denmark, a further development of VINTERMAN, a system for controlling and monitoring winter road maintenance, is in progress. It is a system that is based on all aspects of winter road maintenance to systematically structure and work effectively. For example, Denmark has a number of projects that aim to increase the quality and efficiency of salting, among other things, a project is in progress that aims to adapt the spread and dosage according to forecasts from VINTERMANvia GPS.

Finlanduses a winter road monitoring system called HARJA. It was introduced in 2018 and there is some development in Finland to improve the system. Finland also has development projects to implement a new contracting model, where the starting point is an increased collaboration between the client and the contractor. Pilot studies have shown good results, especially when it comes to the ability to solve emergency situations in a good way. Finland has also implemented new quality levels in winter operations, with particular focus on the needs of business and in particular for heavy transport.

Icelandhas winter road maintenance in its own operation on the state roads and does not really have the same needs as the other Nordic countries when it comes to developing control and follow-up systems. They develop a new platform for the management that aims to improve quality and streamline work. The goal is to increase internal efficiency and to contribute to increased reliability and safety, which contributes to increased user benefit.

In Norway, projects are also underway aimed at streamlining control, suchas ELRAPP and VEGVÆR (road weather), where both aim to contribute to more efficient information gathering for decision-making at various stages in the control process. ELRAPP aims to contribute to efficiency improvements for both the Public Roads Administration(Statens Vegvesen)and the Entrepreneur. It is a digital system that handles everything from control to delivery follow-up. Development projects are currently underway to improve and further develop the system. VEGVÆRis also under development, which is a system for managing weather information and creating road conditionforecasts.

In Sweden, DIGITAL VINTER (digital winter)is being developed, which aims to build up a system support for decision makers. It is about creating the conditions for takingthe correct winter maintenance actionsin a timely manner in order to maintain safe, reliableand accessible roads. DIGITAL VINTERalso aims to be a good tool for monitoring that the customers get the expected service level at the road network.An ongoingproject is to implement a subset of the results from the project DIGITAL VINTERVÄGLAGSINFORMATION (Digital information about winter road conditions). It is expected to contribute to a better delivery follow-up and thus a more even quality of winter road maintenance.

Development of new equipment and new methods for carrying out winter road maintenance is ongoing. Within this development, the trend to implement the measuresin as environmentally as possible is increasingly important, which many of the ongoing projects contribute. There will also be a growing need to develop equipment and methods for winter operation of cycle paths. For example, the R&D program BEVEGELE focuses on developing this part to make walking and cycling a more attractive choice for road users.

Avsikten med att ta fram rapporten är att erbjuda en överblick över de utvecklingsprojekt som bedrivs i de nordiska länderna. Det bidrar till bättre koordinering av utvecklingsprojekt och ger ett bra underlag för initiativ till nya projekt som driver utvecklingen framåt. Syftet är även att bidra till att dela erfarenheter mellan länder och därmed bidra till en utveckling av vinterväghållningen i Norden. Statusrapporten innehåller även ett tematiskt avsnitt där några av länderna belyser viktiga nationella projekt.

The winter maintenance of the road network is an important activity for the road administrations in the Nordic countries. The road administrations put a lot of resources to winter maintenance each year to be able to maintain a high level of service at the road networks. The projects that are running aims to both improve the quality of the winter services and also to increase the efficiency of the winter maintenance activities. 

The restructuring process and the use of contractors for maintenance in the Nordic countries requires changes in the operational management system. Important research areas are methods and strategies to report and reach specific quality standards. There are executed a better basis on decision-making models, i.e. how to take the right steps at the right time. For example, Finland are implementing a new model with contractors with a more integrated dialog with the contractors to respond better and faster at critical circumstances. 

Attempts are being made on improving the management system through new technology and to simplify and modernize the contract system. This requires better description of the tasks and check procedures. The maintenance system VINTERMAN in Denmark is under continuous development. In connection with this project, they are now working with a system linked to GPS-guided salting tied to forecasts for weather and road conditions. Also, in Sweden and Norway there are made attempt with GPS-controlled salting and systems that can regulate the amount of salt automatically depending on weather and road conditions. 

Systems, which through cameras and/or sensors can provide information about weather, road surface condition and friction, are constantly being tested and developed. Further research on weather forecast and weather registration is making progress in most of the countries, example of projects in Norway are ELRAPP and Vägväder. The countries are also starting projects that are trying to support the decision process for supervisors, by giving information related to current and future road conditions. Several countries are also working to integrate the monitoring of correct quality of winter service within their different winter systems. 

In Denmark, different methods are tested to document the salt distribution on the road surface. Development of ploughs and snow-clearing equipment takes place continuously in the Nordic countries. There is also effort made to find possible use of IT and digitalization in the winter maintenance. The Nordic countries are working for against the goal to maintain a high competence both in research for the future and for the individuals who are working with winter maintenance directly. Many of Nordic countries are starting projects that focus more on the needs of pedestrians and cyclists in relation to safe and comfort travel in winter conditions.

This report is INFRACOMS first deliverable D1.1. It addresses the “Understanding of information needs and gaps” component of the project. The aim has been to identify the current priorities and future needs of NRAs for the management of carriageway and bridge assets, specifically in terms of their approach to data collection and monitoring. The approach has been to establish existing knowledge via a review of previous projects, current best practices and standards in data collection and inspection, and a review of current business processes, NRA strategies around data collection and digitalisation etc. The report identifies a set of key imperatives for carriageway and bridge assets covering Availability, Reliability, Environment, Economy and Safety. Each of these is supported by the collection of key condition data, which is used to report technical parameters and performance indicators that can be combined to assess the ability of the asset to meet its key imperatives. A wide range of technologies are identified, which are currently applied to collect the data that supports this assessment.

The consultation shows that there are also gaps between the desired and the current capability for the assessment of these assets. These include gaps in the data, challenges in the ability to collect the data, gaps in the application of the data that is already collected etc. A review of emerging technologies shows that there are tools and technologies that could help to fill these gaps. These could overcome the limitations of current technologies, better integrate new data sources, provide greater flexibility in using current and new data, and provide better analysis. They include remote sensing, Internet of Things (IoT), crowdsourcing, and advanced data processing/visualisation.

This report represents INFRACOMS deliverable D2.1 Appraisal Methodology. It builds upon the deliverables of INFRACOMS Work Package 1 which identified the information needs, gaps and priorities of NRAs in terms of their approach to data collection and monitoring, and a list of current and emerging measurement technologies. This report includes a review of several commonly-used appraisal methodologies that can be used to evaluate the effectiveness, suitability and potential impact of new technologies for an organisation. These methodologies include Technology Readiness Levels (TRLs), Cost Benefit Analysis (CBA), Life Cycle Cost Analysis (LCCA), Risk Assessment, and Multi-Criteria Decision Analysis (MCDA). Elements of these commonly used methodologies are included in the INFRACOMS Appraisal Methodology. The report also includes key highlights from a workshop with NRAs conducted in January 2023 which also fed into the design of the appraisal methodology. The INFRACOMS Appraisal Methodology described here is designed around the technology use case, that is, a particular application of a technology by a NRA. It incorporates three core processes for Pre-Evaluation, Evaluation and Case Studies of technology use cases. It also includes processes for NRAs to define their strategic and technical priorities so that the appraisal process can be tailored to addressing their individual requirements, as identified from Work Package 1.

Effective analysis and visualisation of data is critical for the efficient application of the data provided by carriageway and bridge condition monitoring technologies. It supports better decisions in relation to asset reliability, availability, safety, economy and environment. This report discusses the link between the data provided by monitoring technologies on the properties of assets and how the collected data can be analysed and visualised to provide value in decision support. The next step in the report is to use this understanding to develop an appraisal system which could enable technologies in the INFRACOMS technology database to be appraised (scored) in relation to their abilities for data analysis, visualisation, integration and use in decision support.

The presented system is referred to as the D3.1 scoring system. It consists of four components covering data visualisation, data analysis, integration within current data architectures and potential for practical decision-making. The present D3.1 report primarily examines the components pertaining to data visualisation and data analysis, while the exploration of the other two components, data architecture and decision support, will be carried out in the D3.2 report. It is proposed that the D3.1 scoring system could be used to appraise the capability of monitoring technologies to support asset management decisions, and would become an integral component of the INFRACOMS Appraisal Toolkit. It will also be used to further filter the current INFRACOMS Technology Database 2.0 technologies as part of the Appraisal Toolkit as INFRACOMS completes the development of the toolkit/database within WP2.

Road friction is probably the characteristic of the road that has the greatest importance for traffic safety. When a new surface is laid, road users are normally warned by the warning sign A10 “Warning for slippery road”, with additional sign T22, “On wet road surface”, The signage is carried out as a safety measure. 

The main purpose of this project has been to verify the results from the first study, to know how the friction changes after the introduction of traffic on a newly asphalted road. The ambition was to be able to determine whether a newly laid road section have reduced friction in order to be able to give recommendations on how signage to road users should take place in connection with and after a new pavement layer and at new constructions. 

In this complementary study, friction and macrotexture were measured on roads with different newly laid pavements from shortly before traffic opening until the macrotexture and friction levels had stabilised. The three coatings studied were Stone mastic asphalt (SMA), Dense asphalt concrete (DAC) and Chipseal. One of the objects was studied in more detail through repeated castings and photography of a specific control surface to try to determine how the road surface changes over time. 

This study confirms much of what emerged in the previous study. A new pavement has the highest friction in connection with the release of traffic. The friction then decreases over the next few weeks before starting to increase again to stabilise after about five weeks. This was the case for two of the pavement types (SMA and DAC). The road stretch with Chipseal was already stable after three weeks. The normal time for macrotexture levels to stabilise was between four and five weeks. There was some variation between the different pavement types. It was also found that there can be differences in friction between a conventional pavement and a remixed pavement.

An important factor in the inventory of the road network condition is to be able to geographically position the measurement data at the right place with sufficient accuracy.

In March 2012, the correction service EPOS, used to provide an improved positioning, was shut down. By the commission of the Swedish Transport Administration, VTI has evaluated whether the free correction service EGNOS, operated by ESA, is possible to be used instead. The answer is yes. No systematic differences in the position data could be observed when using the old and the new correction service.