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  • 1.
    Edvardsson, Karin
    et al.
    Dalarna University, School of Technology and Business Studies, Road Technology. KTH.
    Gustafsson, Alf
    Magnusson, Rolf
    Dalarna University, School of Technology and Business Studies, Road Technology.
    Dust suppressants efficiency study: in situ measurements of dust generation on gravel roads2012In: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, Vol. 13, no 1, p. 11-31Article in journal (Refereed)
    Abstract [en]

    Dust suppressants were applied on fifteen 1 km long test sections at four sites in Sweden during three summer seasons with the objective to compare their relative efficiency and determine minimum application rates in Nordic climate. Dust generation from the test sections was measured both visually and by PM10 measurements. All products except lignosulphonate, sugar and bitumen emulsion showed acceptable efficiency. Chloride solutions were the most efficient. Results indicate the possibility to reduce application rates of chlorides by applying them as solutions instead of solids. The minimum application rate for a chloride solution was estimated at 0.8m(3)/km, which is equivalent to a rate reduction of 50% by weight compared with traditionally applied rates of solid chloride. The results are expected to reduce life cycle costs for gravel roads and contribute to environmental gains by reducing the release of dust into the atmosphere and chemicals into the environment.

  • 2.
    Frid, Mikael
    Dalarna University, School of Technology and Business Studies, Construction.
    Solcellsdrivet FTX-system för miljonprogramshus: Tjärna Ängar, Borlänge2013Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project is a feasibility study of including the installation of solar cells and an FTX ventilation system in the renovation of a Swedish million program multi-family ouse. The question concerns whether the energy production of the PV system can match with the energy consumption of the FTX-system. Input data was obtained from:

    • Databases, literature and interviews.
    • Simulations of photovoltaics modules in the computer program PVSYST
    • Modulation of the vents in the computer program MagiCAD

    The aim was primarily to investigate whether it was possible to get a theoretical working system. The economy of the project should also be investigated depending on the results.

    The study showed that it should be theoretically possible to install photovoltaics for electricity generation that is able to cover the FTX system's electricity needs on a yearly basis. The photovoltaics are also expected to produce enough electricity for some other equipment that requires electricity for much of the year. It was also found that it should be possible to get the photovoltaics modules economically viable if a pay-back time of 14 years was used. The method used for these results is thoroughly described and with small changes applicable to a large number of buildings in the Swedish building stock.

    An important conclusion from the project is that if property owner can see 14 years into the future with an investment in solar energy, there is much to be gained. There are already skills, available technologies and products available in order to recover a large portion of the properties' electricity needs through solar energy.

  • 3.
    Jansson, Tom
    Dalarna University, School of Technology and Business Studies, Construction.
    Utvärdering av terrester laserskanning i framställandet av en 3D-modell: Baserat på underlag från ritning och terrester laserskanning av en fackverksbro2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, the implementation of building information modeling (BIM) in the Swedish civil engineering industry has increased. This is due to directives from the government stating that the Swedish Transport Administration (Trafikverket), in greater occurrence, will benefit from the digital possibilities with the BIM concept. Trafikverket is the government agency responsible for the long-term planning and management of public roads, construction in the infrastructure such as tunnels and bridges, and has great influence in the Swedish civil engineering industry. They claim that the key to enhance the use and development of BIM is to raise their demands towards the rest of the industry. Transitioning from a drawing-based to an object-based approach will affect the entire industry. The idea is to be able to handle all the information in 3D-data and the BIM concept throughout the entire life cycle of the construction. To reach that ambition, the already-built constructions need to be represented as 3D-models in terms of being a part of the BIM concept.

    Terrestrial laser scanning is a method of measurement that is being used worldwide for 3D-documentation of complex objects and environments. The result of a scan is comprehensive with low uncertainty of measurement; therefore the method is well suited to assist in the creation of 3D-models.

    The primary aim of the study is to examine the differences between 3D-models, depending on the measurement method that was used to create them.

    An analysis of the current situation in these fields-of-study was made by a literature study to place this thesis in its proper context. Although the two 3D-models were the same exact object, they were created using two different methods of measurement. The models were compared to identify the differences between them.

    The study unveils that the choice of measurement method influences the results of the 3D-model, where the terrestrial laser scanning method could help to improve the quality of the final product. On the other hand, there were areas where the two methods of measurement could complement each other for even better results.

  • 4.
    Nerhagen, Lena
    et al.
    Statens väg- och transportforskningsinstitut, Transportekonomi, TEK.
    Haraldsson, Mattias
    Statens väg- och transportforskningsinstitut, Transportekonomi, TEK.
    Externa kostnader för luftföroreningar från transporter i olika delar av Sverige: sammanfattning och slutsatser från arbetet med luftkvalitet i SAMKOST2018Report (Other academic)
    Abstract [sv]

    Syftet med denna studie har varit att genom några beräkningsexempel klargöra hur de externa kostnaderna för luftföroreningar varierar mellan transportslag och geografi i Sverige, samt att tydliggöra vilka faktorer som ligger bakom dessa skillnader. Syftet är också att sätta in dessa resultat i en internationell kontext för att beskriva hur den svenska situationen förhåller sig till den som råder i andra länder både när det gäller miljöproblemen som orsakas av utsläpp till luft men också arbetet med att utforma miljöarbetet baserat på denna kunskap. Det senare är viktigt för att kunna föra en diskussion om hur Sverige påverkas av och kan bidra till internationellt luftvårdsarbete, framförallt inom EU eftersom den största påverkan av utsläpp från transportsektorn i Sverige sker inom Europa. Vi har i arbetet med SAMKOST studerat effekter på såväl lokal som regional nivå utifrån den metodik som tillämpas inom EU där hälsoeffekter utvärderas baserat på marginella haltförändringar i det som kallas urban eller regional bakgrund. De underlag som tagits fram i SAMKOST-projekten skiljer sig därför från flertalet svenska studier som oftast bedömer effekterna av den totala halten utan hänsyn till källa eller åtgärd. De modelleringar som är grunden för beräkningarna har genomförts av SMHI vilket säkerställer att resultaten är jämförbara mellan de olika transportslagen.

  • 5.
    Oscarsson, Karin
    Dalarna University, School of Technology and Business Studies, Road Technology.
    Evaluation of Dust Suppressants for Gravel Roads: Methods Development and Efficiency Studies2010Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Application of the proper dust suppressant to a gravel road ensures road safety and riding comfort as well as creating a cleaner and healthier environment for residents in buildings adjacent to the road. It also reduces the need and cost for vehicle repair, road maintenance activities, and aggregate supplementation. Both field-based and laboratory research, using newly developed methods, were performed to evaluate the efficiency of various suppressants and the influence such factors as product concentration, leaching, and fine material content have on the efficiency of different products. A significant problem when using dust suppressants is their tendency to leach during rainfall due to their soluble properties. Residual chloride could be detected in the gravel wearing course over a longer period of time than lignosulphonate and, therefore, showed more effective long-term performance. Optimal percentages of fine material for minimal lignosulphonate and chloride leaching were found to be 15 percent by weight and 10-16 percent by weight, respectively. By applying a calcium- or magnesium chloride solution instead of traditionally used solids, the cost for annual dust control, as well as the environmental impact from the release of these chemicals in the environment, can be reduced by 50 percent. Ions of calcium chloride seemed to initiate flocculation of clay particles, thereby preventing them from leaching. Still, the fine material in gravel wearing courses has to be replenished regularly as indicated by studies of the longevity of fine material. Loss up to 80 percent was found after two years. Toxicity tests show that dust suppressant application for dust control purposes, at traditionally used application rates, does not constitute a threat to sensitive aquatic life. Tests on subsoil water samples indicated elevated chloride levels, which possibly could cause corrosion to pipes, but not high enough to flavour drinking water.

  • 6.
    Oscarsson, Karin
    Dalarna University, School of Technology and Business Studies, Road Technology.
    Gravel roads and dust suppression2009In: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402, Vol. 10, no 3, p. 439-469Article in journal (Refereed)
    Abstract [en]

    This review paper deals with the field of dust generation on gravel roads, dust suppressant performance and evaluation techniques. By applying the proper dust suppressant, matching the gravel road condition specific to the site, dust emission can be reduced, thereby providing a healthier ambient air environment, increasing road safety and ride comfort while reducing the need and cost of vehicle repair, road maintenance activities, and aggregate replacement. By applying the proper application rate of the dust suppressant, the cost of annual dust control as well as the environmental impact can be significantly reduced. Suitable measuring techniques for evaluating dust suppressant efficiency will facilitate the choice of the most appropriate dust suppressant and its optimal application rate.

  • 7.
    Oscarsson, Karin
    et al.
    Dalarna University, School of Technology and Business Studies, Road Technology. KTH.
    Ekblad, Jonas
    Magnusson, Rolf
    Dalarna University, School of Technology and Business Studies, Road Technology.
    Methods for quantification of lignosulphonate and chloride in gravel wearing courses2010In: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402, Vol. 11, no 1, p. 171-185Article in journal (Refereed)
    Abstract [en]

    Due to oxidation, breakdown, and leaching, dust suppressants will be lost from the gravel road surface. Methods for residual dust suppressant concentration supervision are a valuable tool for estimating life-length and optimal application rates, and, hence, efficiency of different products. The objective of this study was to identify methods for quantitative analyses of lignosulphonate and chloride, develop and adapt the methods for application on a gravel matrix, and validate the methods using samples collected in-situ. Results strongly suggest that the reliability and repeatability of the developed methods (23 % for lignosulphonate and 30 % for chloride, respectively) are acceptable for determination of relative variations in residual concentrations of dust suppressed gravel wearing courses.

  • 8.
    Oscarsson, Karin
    et al.
    Dalarna University, School of Technology and Business Studies, Road Technology.
    Magnusson, Rolf
    Dalarna University, School of Technology and Business Studies, Road Technology.
    Monitoring of dust emission on gravel roads: development of a mobile methodology and examination of horizontal diffusion2009In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 43, no 4, p. 889-896Article in journal (Refereed)
    Abstract [en]

    Traffic-generated fugitive dust on gravel roads impairs visibility and deposits on the adjacent environment. Particulate matter smaller than 10 µm in diameter (PM10) is also associated with human health problems. Dust emission strength depends on the composition of granular material, road moisture, relative humidity, local climate (precipitation, wind velocity, etc.), and vehicle characteristics. The objectives of this study were to develop a reliable and rapid mobile methodology to measure dust concentrations on gravel roads, evaluate the precision and repeatability of the methodology and correspondence with the currently used visual assessment technique. Downwind horizontal diffusion was studied to evaluate the risk of exceeding the maximum allowed particulate matter concentration in ambient air near gravel roads according to European Council Directive [European Council Directive 1999/30/EC of 22 April 1999 relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air. Official Journal of the European Communities. L163/41.]. A TSI DustTrak Aerosol Monitor was mounted on an estate car travelling along test sections treated with various dust suppressants. Measured PM10 concentrations were compared to visual assessments performed at the same time. Airborne particles were collected in filters mounted behind the vehicle to compare the whole dust fraction with the PM10 concentration. For measuring the horizontal diffusion, DustTraks were placed at various distances downwind of a dusty road section. The mobile methodology was vehicle and speed dependent but not driver dependent with pre-specified driving behaviours. A high linear correlation between PM10 of different vehicles makes relative measurements of dust concentrations possible. The methodology gives continuous data series, mobility, and easy handling and provides fast, reliable and inexpensive measurements for estimating road conditions to make road maintenance more efficient. Good correlations between measured PM10-values, visually assessed dust generation and dust collected in filters were obtained. PM10 seems to be correlated to the whole dust fraction that impairs visibility on gravel roads. A decay in PM10 concentration as a function of distance from the road was observed. Measured particles principally did not travel further than 45 m from the road. The risk of exceeding the PM10 concentration stated in the EC-directive seems small.

  • 9.
    Svenson, Kristin
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    A Microdata Analysis Approach to Transport Infrastructure Maintenance2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Maintenance of transport infrastructure assets is widely advocated as the key in minimizing current and future costs of the transportation network. While effective maintenance decisions are often a result of engineering skills and practical knowledge, efficient decisions must also account for the net result over an asset's life-cycle. One essential aspect in the long term perspective of transport infrastructure maintenance is to proactively estimate maintenance needs. In dealing with immediate maintenance actions, support tools that can prioritize potential maintenance candidates are important to obtain an efficient maintenance strategy.

    This dissertation consists of five individual research papers presenting a microdata analysis approach to transport infrastructure maintenance. Microdata analysis is a multidisciplinary field in which large quantities of data is collected, analyzed, and interpreted to improve decision-making. Increased access to transport infrastructure data enables a deeper understanding of causal effects and a possibility to make predictions of future outcomes. The microdata analysis approach covers the complete process from data collection to actual decisions and is therefore well suited for the task of improving efficiency in transport infrastructure maintenance.

    Statistical modeling was the selected analysis method in this dissertation and provided solutions to the different problems presented in each of the five papers. In Paper I, a time-to-event model was used to estimate remaining road pavement lifetimes in Sweden. In Paper II, an extension of the model in Paper I assessed the impact of latent variables on road lifetimes; displaying the sections in a road network that are weaker due to e.g. subsoil conditions or undetected heavy traffic. The study in Paper III incorporated a probabilistic parametric distribution as a representation of road lifetimes into an equation for the marginal cost of road wear. Differentiated road wear marginal costs for heavy and light vehicles are an important information basis for decisions regarding vehicle miles traveled (VMT) taxation policies.

    In Paper IV, a distribution based clustering method was used to distinguish between road segments that are deteriorating and road segments that have a stationary road condition. Within railway networks, temporary speed restrictions are often imposed because of maintenance and must be addressed in order to keep punctuality. The study in Paper V evaluated the empirical effect on running time of speed restrictions on a Norwegian railway line using a generalized linear mixed model.

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