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Non-exhaust emissions from road transport are an important PM10 source, causing negative health effects. Measures to reduce particulate pollution from roads include dust suppression using hygroscopic solutions and road sweeping. This study investigates if porous pavements, generally used for their better noise reduction and water drainage capacity, can also improve air quality. Atmospheric measurements of NOx and PM10 were performed for 7 months along a road stretch containing two different surfaces, one porous and one dense. The PM10 concentration was significantly lower at the porous pavement during all meteorological conditions. Particle emissions measured behind the wheel of a moving car were also lower at the porous pavement. The reasons for the improved air quality are suggested to be the removal of road dust from the surface into the pores of the pavement, the reduction of the air-pumping suspension forces of the tyres, and the prolonged drying of the surface.

Non-exhaust emissions from road transport are an important PM10 source, causing negative health effects. Measures to reduce particulate pollution from roads include dust suppression using hygroscopic solutions and road sweeping. This study investigates if porous pavements, generally used for their better noise reduction and water drainage capacity, can also improve air quality. Atmospheric measurements of NOx and PM10 were performed for 7 months along a road stretch containing two different surfaces, one porous and one dense. The PM10 concentration was significantly lower at the porous pavement during all meteorological conditions. Particle emissions measured behind the wheel of a moving car were also lower at the porous pavement. The reasons for the improved air quality are suggested to be the removal of road dust from the surface into the pores of the pavement, the reduction of the air-pumping suspension forces of the tyres, and the prolonged drying of the surface.

Mastic asphalt is a material which in Sweden mainly is used as coating for bridges, parking decks, courtyards and terraces. Mastic asphalt is a material built-up by a combination of bitumen (a type of binder), well-graded aggregate (consists of both coarse and fine ballast), filler, sand and sometimes also fine graded macadam. Mastic asphalt is described as a material which in Sweden have potential to expand further. At the same time, it is becoming increasingly popular to construct buildings with solid timber frames. In 2019, the Swedish market for forestry and algaculture was analyzed, after which cross-laminated timber proved to be the construction-material that increases most in popularity. In constructions, mastic asphalt and timber may be combined. In Växjö Sweden for example, a parking deck called Limnologen is constructed with both timber frames and mastic asphalt as pavement. Another example were mastic asphalt and timber have been combined is an enormous car park built in Studen, Switzerland, which have 2142 parking lots. The aim of this master thesis was to develop a temperature-dependent thermal conductivity (for mastic asphalt BPGJA-11) which resulted in temperature development curves that correlated well with the results presented in Ellinor Sanned’s bachelor thesis “Insulation of timber with concrete and cast asphalt”. Sanned performed laboratory work were two different samples of mastic asphalt was tested in a cone calorimeter. The cone calorimeter was set to 51 kW/m2 and Sanned measured the temperature development beneath the mastic asphalt. The thermal conductivities for mastic asphalt were, in this master thesis, developed by using inverse calculation in the finite element program TASEF (Temperature Analysis in Structures Exposed to Fire). To form a reliable setup in TASEF, a sensitivity analysis was initially conducted. Information regarding thermal properties of mastic asphalt at elevated temperatures was in general considered challenging to fi, Mastic asphalt (som i denna sammanfattning benämns som gjutasfalt) är ett material som i Sverige huvudsakligen används som beläggning för broar, parkeringshus, gårdsplaner och terrasser. Gjutasfalt är ett material som är byggt upp av en kombination av bitumen (en typ av bindemedel), välgraderat stenmaterial (består av både grov och fin ballast), filler, sand och ibland även finmakadam. Gjutasfalt beskrivs som ett material som i Sverige har stor potential att expandera. Samtidigt blir det alltmer populärt att konstruera byggnader med solida träkonstruktioner. År 2019 analyserades den svenska marknaden för skog och lantbruk, varpå kors-laminerat trä visade sig vara det konstruktionsmaterial som ökar mest i popularitet. I konstruktioner kan gjutasfalt och trä kombineras. Parkeringshuset Limnologen i Växjö Sverige är ett exempel på en träkonstruktion som kombinerats med gjutasfalt som beläggning. Ett annat exempel är ett enormt parkeringshus i Studen, Schweiz, som har 2142 parkeringsplatser. Målet med denna masteruppsats var att bestämma den temperaturberoende termiska konduktiviteten (för gjutasfalt BPGJA-11) vilken resulterar i en temperaturutvecklingskurva som korrelerar väl med resultaten presenterade i Ellinor Sanneds examensarbete ”Isolering av trä med betong och gjutasfalt”. Sanned genomförde en laboration där två olika prov av gjutasfalt testades i en konkalorimeter. Konkalorimetern var inställd på 51 kW/m2 och Sanned uppmätte temperaturutvecklingen på undersidan av gjutasfalten. De termiska konduktiviteterna för gjutasfalt i denna masteruppsats arbetades fram genom ”inversberäkning” i det finita elementprogrammet TASEF (Temperature Analysis in Structures Exposed To Fire). För att bilda en tillförlitlig uppsättning i TASEF, genomfördes inledningsvis en känslighetsanalys. Information gällande termiska egenskaper av gjutasfalt vid förhöjda temperaturer var generellt sätt svåra att finna. För parametrarna som användes i TASEF gjordes därför antaganden. De term

The performance of asphalt mixtures is significantly affected by the viscoelastic properties of their mastic phase. The analytical approaches used to predict the properties of mastics from their constituents’ properties are limited in their accuracy and potential to handle non-linear material behaviour. An alternative micromechanical finite element modelling approach to calculate the master curves of mastics from the binder and filler phase properties is presented, where the representative volume elements of mastics consist of linear-viscoelastic bitumen matrices and elastic spherical filler particles. For validation, shear relaxation moduli of bitumen and bitumen-filler mastics are measured at (Formula presented.) °C (Formula presented.) °C. Additionally, the model is evaluated and compared with the existing analytical solutions. The results indicate that the proposed approach is advantageous as compared to the analytical solutions, as it allows predicting the mastics’ properties over wider temperature, frequency and material ranges at better agreement with the measurements while giving insight into the micromechanical behaviour., QC 20220809

Mastic asphalt is a material which in Sweden mainly is used as coating for bridges, parking decks, courtyards and terraces. Mastic asphalt is a material built-up by a combination of bitumen (a type of binder), well-graded aggregate (consists of both coarse and fine ballast), filler, sand and sometimes also fine graded macadam. Mastic asphalt is described as a material which in Sweden have potential to expand further. At the same time, it is becoming increasingly popular to construct buildings with solid timber frames. In 2019, the Swedish market for forestry and algaculture was analyzed, after which cross-laminated timber proved to be the construction-material that increases most in popularity. In constructions, mastic asphalt and timber may be combined. In Växjö Sweden for example, a parking deck called Limnologen is constructed with both timber frames and mastic asphalt as pavement. Another example were mastic asphalt and timber have been combined is an enormous car park built in Studen, Switzerland, which have 2142 parking lots. The aim of this master thesis was to develop a temperature-dependent thermal conductivity (for mastic asphalt BPGJA-11) which resulted in temperature development curves that correlated well with the results presented in Ellinor Sanned’s bachelor thesis “Insulation of timber with concrete and cast asphalt”. Sanned performed laboratory work were two different samples of mastic asphalt was tested in a cone calorimeter. The cone calorimeter was set to 51 kW/m2 and Sanned measured the temperature development beneath the mastic asphalt. The thermal conductivities for mastic asphalt were, in this master thesis, developed by using inverse calculation in the finite element program TASEF (Temperature Analysis in Structures Exposed to Fire). To form a reliable setup in TASEF, a sensitivity analysis was initially conducted. Information regarding thermal properties of mastic asphalt at elevated temperatures was in general considered challenging to fi, Mastic asphalt (som i denna sammanfattning benämns som gjutasfalt) är ett material som i Sverige huvudsakligen används som beläggning för broar, parkeringshus, gårdsplaner och terrasser. Gjutasfalt är ett material som är byggt upp av en kombination av bitumen (en typ av bindemedel), välgraderat stenmaterial (består av både grov och fin ballast), filler, sand och ibland även finmakadam. Gjutasfalt beskrivs som ett material som i Sverige har stor potential att expandera. Samtidigt blir det alltmer populärt att konstruera byggnader med solida träkonstruktioner. År 2019 analyserades den svenska marknaden för skog och lantbruk, varpå kors-laminerat trä visade sig vara det konstruktionsmaterial som ökar mest i popularitet. I konstruktioner kan gjutasfalt och trä kombineras. Parkeringshuset Limnologen i Växjö Sverige är ett exempel på en träkonstruktion som kombinerats med gjutasfalt som beläggning. Ett annat exempel är ett enormt parkeringshus i Studen, Schweiz, som har 2142 parkeringsplatser. Målet med denna masteruppsats var att bestämma den temperaturberoende termiska konduktiviteten (för gjutasfalt BPGJA-11) vilken resulterar i en temperaturutvecklingskurva som korrelerar väl med resultaten presenterade i Ellinor Sanneds examensarbete ”Isolering av trä med betong och gjutasfalt”. Sanned genomförde en laboration där två olika prov av gjutasfalt testades i en konkalorimeter. Konkalorimetern var inställd på 51 kW/m2 och Sanned uppmätte temperaturutvecklingen på undersidan av gjutasfalten. De termiska konduktiviteterna för gjutasfalt i denna masteruppsats arbetades fram genom ”inversberäkning” i det finita elementprogrammet TASEF (Temperature Analysis in Structures Exposed To Fire). För att bilda en tillförlitlig uppsättning i TASEF, genomfördes inledningsvis en känslighetsanalys. Information gällande termiska egenskaper av gjutasfalt vid förhöjda temperaturer var generellt sätt svåra att finna. För parametrarna som användes i TASEF gjordes därför antaganden. De term

One possible solution to reduce noise resulting from tyre-pavement interaction is to use a porous pavement surface. A porous surface will reduce noise by decreasing air pressure gradients in the tyre-pavement contact as well as by decreasing the acoustical impedance of the road surface and reducing the horn effect. While reducing noise, other functional aspects of a pavement such as abrasion wear which impacts on air pollution through generation and suspension of particles, friction and rolling resistance need to be addressed. This paper analyses the acoustical behaviour of a Double Layered Porous Asphalt (DLPA), applied in the city of Linköping, Sweden, as a solution to mitigate noise, compared to a non-porous Stone Mastic Asphalt (SMA) pavement used as reference. The analysis is based on Close Proximity noise measurements, both in absolute value and as frequency spectra, acoustical homogeneity over the surface length and sound absorption measurements. The acoustic analysis is combined with analyses of air quality measurements of PM10 (Particulate Matter with aerodynamic diameter < 10 µm) from two Tapered Element Oscillating Microbalance (TEOM) measurement stations placed near each different pavement section. The initial results indicate that the porous pavement results in a noise reduction of up to 5 dB for light vehicles, and up to 4 dB for heavy vehicles. So far, the DPLA shows approximately 52 % lower PM10 concentrations than the SMA. It should be noted that PM10 is influenced also by meteorological conditions, like humidity, background sources as well as vehicle properties, e.g. use of studded tyres, and that some of the observed decrease can be due to other aspects than porosity e.g. road surface moisture and wind direction. In conclusion, the use of a porous pavement shows promising results from both acoustical and air quality aspects, given the initial, short term results., QC 20200618

In Sweden, during recent years, a new type of mixing protocol has been applied, in which the order of mixing is changed from the conventional method. Improved workability and diminished mixing and compaction energy needs have been important drivers for this. Considering that it is the mastic phase, which is modified by changing the mixing order, it provides an interesting case study for explaining the mechanisms of workability in connection with the mastic phase. To do so, an analytical viscosity framework was combined with a mixture morphology framework to upscale to the mixing level and tribology principles to explain the interaction between the mastic and the aggregates. From the mastic viscosity protocol, it was found that the mixing order significantly affects the resulting mastic viscosity. To analyse the effect of this on the workability and resulting mixture performance, X-ray computed tomography was used to analyse mixtures produced by the two different mixing sequences. Mechanical testing was utilised to determine the long-term mechanical performance. In this part of the study, mastic viscosity as a function of particle concentration and distribution was directly coupled to improved mixture workability and enhanced long-term performance., QC 20151127

This thesis studies the strain response of mastic asphalt to arbitrary tension, arbitrary compression, alternating tension/compression, loading, zigzag loading and sinusoidal loading. In order to model the strain response to different loading histories, the scissors model is employed. Matlab modules are developed that are able to predict strain response not only for creep loading but also for other types of non constant stress loading such as zigzag loading and sinusoidal loading. In addition, another phenomological model, i.e. the viscoelastoplastic continuum damage model, is summarized and discussed in detail with respect to its applicability for the available data set.

This thesis studies the strain response of mastic asphalt to arbitrary tension, arbitrary compression, alternating tension/compression, loading, zigzag loading and sinusoidal loading. In order to model the strain response to different loading histories, the scissors model is employed. Matlab modules are developed that are able to predict strain response not only for creep loading but also for other types of non constant stress loading such as zigzag loading and sinusoidal loading. In addition, another phenomological model, i.e. the viscoelastoplastic continuum damage model, is summarized and discussed in detail with respect to its applicability for the available data set.

This paper focuses on the addition of commercial wax as flow improver in polymer modified bitumen intended for use in mastic asphalt pavements under Nordic climatic conditions. Different aspects are dealt with. The aim of the project is to make mastic asphalt used in Sweden today (for bridges, parking decks etc.) more environment friendly and easier to handle. However, wax modification must not have any noticeable negative impact on the performance of mastic asphalt at medium and lower temperatures. The project involves laboratory testing of wax and polymer modified binder mixtures as well as mastic asphalt mixtures. Effects of adding two commercial waxes to one polymer modified bitumen have been studied. The results show that both waxes have a flow improving/viscosity depressant impact on the polymer modified bitumen at higher temperatures, indicating a possible lower laying temperature for the mastic asphalt if modified with such waxes. Moreover, there is a stiffening effect at medium and high temperatures (below placing temperature), indicating a certain positive effect on stability. Concerning low temperature performance, there are results indicating some negative impact on crack susceptibility at low temperatures, more by the addition of one of the waxes than by addition of the other. However, it could be concluded that using up to at least 4% of either wax additive will improve workability for the mastic asphalt product under investigation making it possible to lower working temperatures without seriously affecting its good performance in any negative way., QC 20101214

This dissertation describes the research into surfacings of orthotropic steel bridge decks. The motive for this research is the frequently reported problems of this type of structures including cracking and rutting of surfacing materials and fatigue related cracks in the steel plate. An intensive experimental program was carried out on three wearing course materials, namely mastic asphalt, guss asphalt and an open synthetic material. The program also included on a bituminous based membrane material. The results of the experimental program were analysed to characterise the complex mechanical behaviour of the different materials. Within the framework of this research, models that describe the response of the surfacing materials were developed, including a newly developed unified model that describes the time-temperature characteristics of many road materials. Furthermore, constitutive relations for elastic as well as inelastic response of the materials were developed. All the developed models were implemented in the Finite Element System CAPA-3D. For verification of the different models results of laboratory tests and full-scale experiments in the LINTRACK APT facility were used. Furthermore, a scientific approach in which the non-linear response of the materials, the geometry and the load are well presented, was used to give an insight into the interaction between the different components of the structure and the vehicle at different temperatures. Because this scientific approach is too sophisticated and expensive for routine analyses and design of the structure, a practical design concept is proposed. In this concept, the geometry and the load are well presented, but the material behaviour is simplified, Civil Engineering and Geosciences

The high costs of maintenance related to pavement wear have caused many countries to prohibit the use of studded tyres. In Japan and Norway, regulations have also been based upon the health aspects of the road dust. In Japan studded tyres are prohibited and in Norway, restrictions have been placed on the use of studded tyres in some larger cities. In Sweden, wear particles from pavements, tyres, brakes and winter sanding/salting, have received a lot of attention the last few years. The reason for this is that measurements have shown that these particles are the main reason that the upcoming environmental quality standard for inhalable particles (PM10) will not be reached in many cities. The problem mainly occurs during dry episodes in winter and early spring and is mainly a result of studded tyre use and winter maintenance. A lot of new knowledge about wear particles is needed in order to develop cost-effective measures to deal with them. A great advantage is the possibility to study aerosols from each source both separately and in different combinations in a controlled environment. At VTI (Swedish National Road and Transport Research Institute) a road simulator (PVM), previously used for pavement and tyre wear studies, is used as a wear particle generator. The PVM can be equipped with different pavements and tyres and even friction materials such as sand can be applied. The PVM can be used at speeds up to 70 km/h and the pavement can be dry or wet. Also the temperature in the hall can be regulated below zero degrees centigrade. In this paper some results from the WearTox project will be presented. The production of PM10 from two pavements worn by studded tyres and friction tyres has been studied as well as the physical and chemical properties of the wear particles produced.

This dissertation describes the research into surfacings of orthotropic steel bridge decks. The motive for this research is the frequently reported problems of this type of structures including cracking and rutting of surfacing materials and fatigue related cracks in the steel plate. An intensive experimental program was carried out on three wearing course materials, namely mastic asphalt, guss asphalt and an open synthetic material. The program also included on a bituminous based membrane material. The results of the experimental program were analysed to characterise the complex mechanical behaviour of the different materials. Within the framework of this research, models that describe the response of the surfacing materials were developed, including a newly developed unified model that describes the time-temperature characteristics of many road materials. Furthermore, constitutive relations for elastic as well as inelastic response of the materials were developed. All the developed models were implemented in the Finite Element System CAPA-3D. For verification of the different models results of laboratory tests and full-scale experiments in the LINTRACK APT facility were used. Furthermore, a scientific approach in which the non-linear response of the materials, the geometry and the load are well presented, was used to give an insight into the interaction between the different components of the structure and the vehicle at different temperatures. Because this scientific approach is too sophisticated and expensive for routine analyses and design of the structure, a practical design concept is proposed. In this concept, the geometry and the load are well presented, but the material behaviour is simplified, Civil Engineering and Geosciences

The high costs of maintenance related to pavement wear have caused many countries to prohibit the use of studded tyres. In Japan and Norway, regulations have also been based upon the health aspects of the road dust. In Japan studded tyres are prohibited and in Norway, restrictions have been placed on the use of studded tyres in some larger cities. In Sweden, wear particles from pavements, tyres, brakes and winter sanding/salting, have received a lot of attention the last few years. The reason for this is that measurements have shown that these particles are the main reason that the upcoming environmental quality standard for inhalable particles (PM10) will not be reached in many cities. The problem mainly occurs during dry episodes in winter and early spring and is mainly a result of studded tyre use and winter maintenance. A lot of new knowledge about wear particles is needed in order to develop cost-effective measures to deal with them. A great advantage is the possibility to study aerosols from each source both separately and in different combinations in a controlled environment. At VTI (Swedish National Road and Transport Research Institute) a road simulator (PVM), previously used for pavement and tyre wear studies, is used as a wear particle generator. The PVM can be equipped with different pavements and tyres and even friction materials such as sand can be applied. The PVM can be used at speeds up to 70 km/h and the pavement can be dry or wet. Also the temperature in the hall can be regulated below zero degrees centigrade. In this paper some results from the WearTox project will be presented. The production of PM10 from two pavements worn by studded tyres and friction tyres has been studied as well as the physical and chemical properties of the wear particles produced.

The High Coast Bridge is one of the world´s longest suspension bridges. The waterproofing and pavement for this bridge had to be chosen with care. A lowest average temperature of -–20°C, a minimum temperature of -–40°C and a maximum temperature of +30°C have been recorded in this reigon of Sweden. To be able to recommend the most suitable system for the bridge, a research project was started by the Swedish National Road Administration as early as 1992. As a result of research and testing during the project period, a suitable system for the bridge was suggested by the Swedish Road Administration in 1996. The waterproofing and pavement system chosen for the High Coast bridge consists of an epoxy primer system, an SBS-modified bituminous sheet layer, coarse aggregate mastic asphalt with SBSmodified bitumen and split mastic asphalt with SBS-modified bitumen and fibres. Various waterproofing and pavement producst and systems were tested in the research project, both separately and in different combinations for evaluation. Laboratory testing was performed at the Swedish National Road and Transport Research Institute (VTI), starting in 1992. Testing covered characteristics and performance of the various products and systems at low and high temperatures. Important parameters studied for total built-up systems included adhesion (to steel deck and between layers), shear and sliding resistance. Systems with SBS-modified bituminous sheet (3.5 mm thick), SBS-modified fine aggregate mastic asphalt (4 mm) and conventional fine aggregate mastic asphalt (4 mm) were compared. In 1993, eight different systems were laid on a steel bridge at Pitsund (further north than the High Coast Bridge) for evaluation on site and laboratory testing at VTI. Fatigue tests of the entire waterproofing and pavement system were performed for four possible systems and the reference system at the Otto Graf Institute (FMPA) in Stuttgart. Testing was performed in accordance with the German ZTV-BEL ST-92 “Dau

The High Coast Bridge is one of the world´s longest suspension bridges. The waterproofing and pavement for this bridge had to be chosen with care. A lowest average temperature of -–20°C, a minimum temperature of -–40°C and a maximum temperature of +30°C have been recorded in this reigon of Sweden. To be able to recommend the most suitable system for the bridge, a research project was started by the Swedish National Road Administration as early as 1992. As a result of research and testing during the project period, a suitable system for the bridge was suggested by the Swedish Road Administration in 1996. The waterproofing and pavement system chosen for the High Coast bridge consists of an epoxy primer system, an SBS-modified bituminous sheet layer, coarse aggregate mastic asphalt with SBSmodified bitumen and split mastic asphalt with SBS-modified bitumen and fibres. Various waterproofing and pavement producst and systems were tested in the research project, both separately and in different combinations for evaluation. Laboratory testing was performed at the Swedish National Road and Transport Research Institute (VTI), starting in 1992. Testing covered characteristics and performance of the various products and systems at low and high temperatures. Important parameters studied for total built-up systems included adhesion (to steel deck and between layers), shear and sliding resistance. Systems with SBS-modified bituminous sheet (3.5 mm thick), SBS-modified fine aggregate mastic asphalt (4 mm) and conventional fine aggregate mastic asphalt (4 mm) were compared. In 1993, eight different systems were laid on a steel bridge at Pitsund (further north than the High Coast Bridge) for evaluation on site and laboratory testing at VTI. Fatigue tests of the entire waterproofing and pavement system were performed for four possible systems and the reference system at the Otto Graf Institute (FMPA) in Stuttgart. Testing was performed in accordance with the German ZTV-BEL ST-92 “Dau