A large portion of an airport property is occupied by runways and taxiways, which must be kept in excellent condition to ensure the safety of the airplanes, and the people on board. Any free objects on the airfield can cause damage to aircraft and are a possible danger to both the airplanes and the passengers. However, deterioration of the concrete airfield can be a major hazard and the presence of de-icing and anti-icing fluids may accelerate degradation. The focus of this project was the evaluation and assessment of aircraft de-icing and anti-icing fluids on the deterioration of airfield concrete. These fluids are used to remove and prevent snow and ice formation on aircraft by lowering the freezing temperature of water. The primary component in both fluids is ethylene glycol, while additives, which are proprietary and unknown, are mixed in to control various properties. Very little research has been done regarding the effect of the de-icer and anti-icers on the concrete deterioration. The aim of this study was to gain a better understanding of its influence on the deterioration of airfield concrete through a series of mechanical and electro-chemical tests, as well as microscopic and elemental analysis. Based on the comparative experiments and analyses performed using water, ethylene glycol, de-icer, and anti-icer, it appears that de-icing fluids do not prematurely cause concrete deterioration. In addition, experimental procedures in this study utilized the de-icing fluids as a concentrate, which are unrealistic conditions on an airfield, where dilution occurs from the addition of water and the presence of snow and ice. There was precipitate formation in all cases of cement paste exposure to de-icing fluid, however, which indicates that reactions are occurring and should be investigated further to determine the long term effects on concrete. With respect to the scope of this study, it was determined that the use of de-icers and anti-icers cause no significant detrimental effects on concrete mechanical properties and durability.

A large portion of an airport property is occupied by runways and taxiways, which must be kept in excellent condition to ensure the safety of the airplanes, and the people on board. Any free objects on the airfield can cause damage to aircraft and are a possible danger to both the airplanes and the passengers. However, deterioration of the concrete airfield can be a major hazard and the presence of de-icing and anti-icing fluids may accelerate degradation. The focus of this project was the evaluation and assessment of aircraft de-icing and anti-icing fluids on the deterioration of airfield concrete. These fluids are used to remove and prevent snow and ice formation on aircraft by lowering the freezing temperature of water. The primary component in both fluids is ethylene glycol, while additives, which are proprietary and unknown, are mixed in to control various properties. Very little research has been done regarding the effect of the de-icer and anti-icers on the concrete deterioration. The aim of this study was to gain a better understanding of its influence on the deterioration of airfield concrete through a series of mechanical and electro-chemical tests, as well as microscopic and elemental analysis. Based on the comparative experiments and analyses performed using water, ethylene glycol, de-icer, and anti-icer, it appears that de-icing fluids do not prematurely cause concrete deterioration. In addition, experimental procedures in this study utilized the de-icing fluids as a concentrate, which are unrealistic conditions on an airfield, where dilution occurs from the addition of water and the presence of snow and ice. There was precipitate formation in all cases of cement paste exposure to de-icing fluid, however, which indicates that reactions are occurring and should be investigated further to determine the long term effects on concrete. With respect to the scope of this study, it was determined that the use of de-icers and anti-icers cause no significant detrimental effects on concrete mechanical properties and durability.

A comprehensive study was conducted on the effects of de-icer and anti-icer chemicals on cement-based materials. Portland cement mortars and concretes were exposed to over 16 chloride-based and non-chloride-based generic and commercial products and changes in cement-based material properties were measured. Deleterious chemical actions of several types of these products on cement-based materials were observed, departing from the well-known position that attributes the concrete damage from such salts mainly to physical actions under freezing and thawing exposure. Independent of freezing and thawing exposure, mortars and concretes exposed to concentrated calcium chloride and magnesium chloride solutions were found to undergo severe deterioration whereas those exposed to sodium chloride did not. The mechanisms of deterioration are complex with factors such as concentration, temperature, and availability of calcium hydroxide playing important roles. It was found that the formation of calcium oxychloride of the form 3Ca(OH)2.CaCl2.12H2O, and the 3- and 5-form magnesium oxychloride, 3Mg(OH)2.MgCl2.8H2O and 5Mg(OH)2.MgCl2.8H2O, were the main causes for the severe deterioration, and to a lesser extent brucite, gypsum, and magnesium silicate hydrate (M-S-H). The instability of these oxychloride compounds when subjected to conditions normally encountered in sample preparation is suggested as the reason why field investigations have failed to relate distressed concrete to chemical attack by such de-icer and anti-icer chemicals. Concentrated solutions of calcium magnesium acetate were also found to be harmful to cement-based materials by dissolution of calcium hydroxide and formation of calcium acetate hydrate, whereas low concentrated solutions tended to cause slow deterioration by magnesium attack forming brucite, gypsum, and M-S-H. Potassium acetate chemicals did not cause significant deterioration in mortars when these products were diluted (25% by mass), but undiluted products (50% by mass) caused considerable distress in concrete specimens. The combined effect of chemical attack impairing concrete mechanical properties and subsequent salt scaling damage was proposed as the most likely mechanisms of field deterioration.

A comprehensive study was conducted on the effects of de-icer and anti-icer chemicals on cement-based materials. Portland cement mortars and concretes were exposed to over 16 chloride-based and non-chloride-based generic and commercial products and changes in cement-based material properties were measured. Deleterious chemical actions of several types of these products on cement-based materials were observed, departing from the well-known position that attributes the concrete damage from such salts mainly to physical actions under freezing and thawing exposure. Independent of freezing and thawing exposure, mortars and concretes exposed to concentrated calcium chloride and magnesium chloride solutions were found to undergo severe deterioration whereas those exposed to sodium chloride did not. The mechanisms of deterioration are complex with factors such as concentration, temperature, and availability of calcium hydroxide playing important roles. It was found that the formation of calcium oxychloride of the form 3Ca(OH)2.CaCl2.12H2O, and the 3- and 5-form magnesium oxychloride, 3Mg(OH)2.MgCl2.8H2O and 5Mg(OH)2.MgCl2.8H2O, were the main causes for the severe deterioration, and to a lesser extent brucite, gypsum, and magnesium silicate hydrate (M-S-H). The instability of these oxychloride compounds when subjected to conditions normally encountered in sample preparation is suggested as the reason why field investigations have failed to relate distressed concrete to chemical attack by such de-icer and anti-icer chemicals. Concentrated solutions of calcium magnesium acetate were also found to be harmful to cement-based materials by dissolution of calcium hydroxide and formation of calcium acetate hydrate, whereas low concentrated solutions tended to cause slow deterioration by magnesium attack forming brucite, gypsum, and M-S-H. Potassium acetate chemicals did not cause significant deterioration in mortars when these products were diluted (25% by mass), but undiluted products (50% by mass) caused considerable distress in concrete specimens. The combined effect of chemical attack impairing concrete mechanical properties and subsequent salt scaling damage was proposed as the most likely mechanisms of field deterioration.

För att motverka halka på vägar och skapa bättre framkomlighet och trafiksäkerhet för trafikanter under vintersäsonger, används halkskyddsmedel på vägarna. I dagsläget och sannolikt under en överskådlig framtid innebär det att man använder natriumkloridbaserade medel NaCl i form av vägsalt då NaCl är det mest effektiva samt kostnadseffektiva medlet för halkskydd. Trots att NaCl är det mest effektiva medlet mot halka kan vägsalt samtidigt orsaka vissa negativa effekter på miljön. Studier visar på att vägsaltet sprider sig i miljön genom flera olika transportmekanismer vilket gör vägsaltet till ett komplext problem. Vägsalt påverkar bland annat träden negativt, långvarig exponering för salt kan försvaga träden och leda till att träden dör. Klimatförändringar har potentialen att även i framtiden öka, om än kontraintuitivt, efterfrågan på vägsalt i städer med kallt vinterklimat. Därav behövs ett proaktivt tillvägagångssätt för att minska de negativa effekterna vägsaltet har på miljön och träden. Forskning visar på att det finns behov av mer kunskap samt kvalitativa studier gällande vägsalt och dess miljöeffekter. Hittills har det inte funnits någon probabilistisk metod för att bedöma miljörisken vägsalt utgör för gatuträden för att ge nödvändigt stöd till beslutsfattare. Riskbedömningar och riskhantering är viktiga medel i beslutstödjande arbeten. Syftet med denna studie har därav varit att utveckla, tillämpa och utvärdera modeller för övergripande miljöriskbedömningar av vägsalt som ett miljöförorenande ämne. För studien valdes två gator i Stockholms stad, Vasagatan samt Sockenvägen. Studien inleds med litteraturstudier som behandlar trädens roll i urbana miljöer, vägsaltets spridningsvägar, vägsaltets påverkan på träden och miljön samt olika saltmanagementmetoder. Baserade på data från litteraturstudien utfördes miljöriskbedömningar för träd-och vegetation, grundvatten samt jord i studieområdena. En riskbedömning utfördes för ett scenario där vägsalt inte används på vägarna och risken detta kan utgöra för människor. Vidare utvecklades och arbetades det fram olika åtgärdsförslag för studieområdena. Åtgärdsförslagen bedömdes och graderades i en bedömningsmatris. Sammantaget belyser studien vikten av att kontinuerligt samla in saltdata, skapa förståelse för vägsaltets spridningsvägar, utföra miljöriskanalyser på flera miljöområden gällande vägsalt, arbeta fram olika saltmanagementmetoder samt upprätta policyn för vägsalt i syfte att minimera vägsaltets skadliga effekter på träden och ekosystemen i Stockholms stad. / To prevent slippery roads and ensure better traffic safety for road-users during winter seasons, de-icing agents are used on the roads. Currently and probably for the foreseeable future this means using the sodium chloride-based agent NaCl in the form of road salt, which currently is the most effective and cost-effective de-icer. Despite benefits for road safety road salt can at the same time pose negative effects on the environment. Several studies describe how road salt spreads in the environment through several different transport mechanisms, which deems road salt a complex problem. Road salt affects, among other things trees negatively, prolonged exposure to salt weakens the trees and can lead to the death of the damaged trees. Climate change has the potential to even in the future, albeit counterintuitively, increase the demand for NaCl based road salt, during winter seasons in cities with continental climate, as road salt is a cost-effective agent. Hence, a proactive approach is needed to be able to reduce the negative effects road salt has on the environment and trees. Research shows there is a need for more knowledge and qualitative studies regarding road salt and its environmental effects and the effects on street trees. Until now there has been no probabilistic method to assess the environmental risks posed by road salt on street trees to provide the necessary support to decision makers. Environmental risk assessments and risk management are important tools in decision support. The aim of this study has therefore been to develop, apply and evaluate a model for an overall environmental risk assessment of road salt as a pollutant. For the study two streets were chosen in the city of Stockholm, Vasagatan and Sockenvägen. The study is introduced with literature studies on the roles of trees in urban environments, the dispersal paths of road salt, the impact of road salt on trees and the environment and road salt management methods. Based on data from the literature study an environmental risk assessment was carried out for trees and vegetation, ground water and soil in the study areas. A risk assessment was carried out for a scenario where road salt is not applied on the roads and the risk this may pose to human health. Furthermore, various suggestions for mitigation methods for the study areas were developed. The proposed mitigation measures were assessed and graded in an assessment matrix. The study highlights the importance of collecting road salt data continuously over several seasons, creating an understanding of road salt's dispersal paths, performing environmental risk assessments and analysis on several environmental areas regarding road salt. The study also highlights the need for developing different salt management methods and establishing policies aimed to reduce harmful effects of road salt on the trees and ecosystems in the city of Stockholm.

En viabilité hivernale, la prévision de l’état de surface des infrastructures s’avère indispensable, et permet une anticipation, une meilleure coordination et une efficacité d’intervention des services d’exploitation. La majorité des pays dispose de modèles de prévision de la température de surface d'infrastructures et des routes en particulier (TSR). La complexité de ces outils d’aide à la décision est croissante, pour servir au mieux les usagers et l’exploitant. Le microclimat urbain influence le bilan énergétique de surface selon différents processus : radiatifs, aérodynamiques et hydrologiques. Néanmoins, d’autres processus physiques anthropiques influencent cette TSR, tel que le trafic. Des travaux ont été menés par le passé concernant l’apport énergétique du trafic dans le bilan thermique de la ville. Celui-ci a fait l’objet d’études sur les périodes estivales et les îlots de chaleur urbains associés. Cependant, dans les cas de dégradations des conditions hivernales de circulation, ces apports énergétiques ont été intégrés de façon marginale dans la modélisation des paramètres de surface de la route. L’absence de cette contribution du trafic dans la modélisation du bilan énergétique de surface explique, dans une certaine limite, la prévision imparfaite de l’état de surface de la route. La bibliographie recense plusieurs études conduites afin d’identifier et de quantifier ces effets du trafic. Elles n'ont pas ou peu traité la perte ou le gain d'énergie causé par le passage des véhicules sur le bilan énergétique de surface, ou sur la modélisation de la TSR. Dans la présente étude, deux approches ont été proposées pour paramétrer le trafic dans le modèle numérique Town Energy Balance (TEB), l'une globale et la seconde détaillée. Leur analyse comparée indique que la seconde a significativement amélioré les résultats de la modélisation de la TSR. Les apports thermiques du trafic ont augmenté la TSR de 2 à 4°C pour la rapprocher des mesures expérimentales (écart de 0.5 à 1°C en moyenne). Elle est le résultat de l’effet cumulatif des différents processus physiques associés au trafic, et varie en fonction de ses paramètres (densité, vitesse de circulation, fluidité, etc.). Une étude de sensibilité a été menée afin d’apprécier les processus physiques responsables de l’amélioration de la TSR. Les résultats indiquent que l’effet turbulent, la densité de flux radiatif ainsi que la densité de flux due aux frottements des pneumatiques contribuent le plus à l'augmentation la TSR. Néanmoins la contribution énergétique de chacun de ces processus dépend à la fois des paramètres du trafic et des conditions météorologiques. Cette étude a présenté également une analyse préliminaire de l’influence de la lame d’eau présente en surface sur la TSR. Cette dernière décroit en fonction de l’épaisseur de la lame d’eau. Les facteurs anthropiques tels que le trafic et l’adjonction de fondants routiers sur la lame d’eau présente en surface sont décrits et discutés, et une paramétrisation proposée en perspectives / In winter maintenance, forecasting the infrastructure surface status is mandatory, to allow anticipation, better coordination and efficiency of services. The majority of countries have forecast models of the infrastructure surface temperature and especially roads one (RST). The complexity of these decision tools is growing, to best serve the users and managers. The urban microclimate influences the surface energy balance according to various processes: radiative, aerodynamic and hydrologic. However, other anthropogenic physical processes influence this RST, such as traffic. Studies have been carried out in the past about the traffic heat input in the town heat balance. These were conducted on the summer periods and associated urban heat islands. However, in case of traffic in adverse winter conditions, these energy contributions were marginally integrated into the modeling of the road surface parameters. The absence of this traffic's contribution in the surface energy balance modeling explains, to a given limit, the imperfect forecasting of road surface status. The literature identifies several studies conducted to identify and to quantify these effects of traffic. They have insufficiently or not treated the loss or gain on energy caused by circulating vehicles on the surface energy balance, or on modeling the RST. In this study, two approaches have been proposed to parameterize the traffic in the Town Energy Balance (TEB) numerical model, this first one being overall and the second one detailed. Their comparative analysis indicates that the second significantly improved the results of the RST modeling. The traffic heat inputs increased RST by 2 to 4°C, results being then closer to experimental measurements (average difference of 0.5 to 1°C). It is the result of the cumulative effect of the various traffic physical processes, and varies according to its parameters (density, vehicle velocity, fluidity, etc.). A sensitivity analysis was conducted to assess the physical processes responsible for the improvement of the RST. The results indicate that the turbulent effect, the radiative heat flux and flux density due to tires friction represent the greatest contribution to RST increase. Nevertheless the energy contribution of each of these processes depends both traffic parameters and weather conditions. This study also presented a preliminary analysis of the influence of a water layer over the surface on the RST. The latter decreases as a function of the thickness of the water layer. Anthropogenic factors such as traffic and the addition of de-icing products into the water layer present on the surface are described and discussed, and a parameterization proposed as a perspective