Despite the widespread recycling of Reclaimed Asphalt Pavement (RAP), a large portion of it is still wasted. One of the main reasons is the concern with the performance of high RAP mixtures. Asphalt binder aging and subsequent rejuvenation is one source of uncertainty. Rejuvenators are frequently added to high RAP mixes to enhance the properties of the binder. This enhancement is often perceived as simply lowering the viscosity. Two important parameters that are not adequately addressed by existing methods are durability and homogeneity of the recycled binder. This research investigated these two concerns and provided quantitative indicators to measure them. The durability of rejuvenated binders was investigated through studying their long-term aging. Superpave PG tests and aging procedures were used for this purpose. Results indicated that the type and dosage of the rejuvenator has a significant impact on the aging of a rejuvenated binder. While using a proper rejuvenator can prolong the life of the binder, choosing a wrong product causes the binder to age significantly faster. The asphalt film that coats aggregates is not necessarily homogeneous. Different layers of the film are affected differently by aging and rejuvenation processes. A staged extraction method was implemented to provide representative samples from the different layers of asphalt. The stiffness of each sample was measured by Dynamic Shear Rheometer testing. Results indicated that most of the rejuvenator is absorbed by outer layers immediately after blending. As the mixture ages, the rejuvenator continues diffusing into the inner layers. Outer layers are also affected more intensely by the aging. The coupled effects of aging and rejuvenation make the recycled binder more homogeneous than virgin asphalt. This property can facilitate the use of higher target PG values for recycled binders without compromising the long-term performance. This research introduces two quantitative measures, critical PAV time and Durability Index, for evaluating the durability of recycled binders and two other parameters, Stiffness Gradient Factor and Homogeneity Index for describing the binder film homogeneity. These indicators and the knowledge obtained from this research make it possible to design and evaluate the binder rejuvenation process in a more effective manner.

När priset på naturtillgångar ökar samt att industrier måste ställa om till en mer hållbar verksamhet innebär detta även en omställning för asfaltsindustrin. Ett sätt för att använda mer återvunnet material i asfaltsindustri är att använda bindemedlet från gammal asfaltsmassa (eng.: reclaimed asphalt pavement, RAP). Detta kan dock inte göras utan komplikationer och därför måste bindemedlet föryngras innan för att kompensera för faktorer så som hög styvhet, låg krakning och trötthetsförmåga samt dålig anti-åldring förmåga hos RAPen. I det här projektet har två olika typer av föryngringsmedel använts; ett växtoljebaserat och ett petroleumbaserat mjukbitumen. Detta för att se om det var möjligt att använda förnybart och återvunnet material i bindemedlet men fortfarande uppnå samma prestanda som konventionellt bindemedel. Två blandningar gjordes hjälp av de två olika föryngringsmedlen och RAPen och analyserades parallellt med ett referensmaterial. Analyserna delades upp i två kategorier: reologi och kemi. Analyserna som föll under reologikategorin var mjukpunkt- och penetrationsanalyser, samt analyser med en dynamisk skjuvning reometer (eng.: dynamic shear rheometer, DSR) och en böjbalksreometer (eng.: bending beam rheometer, BBR). Under kemikategorin fanns analysmetoderna tunnskiktskromatografi med flamjoniseringsdetektor (TLC-FID) och Fourier transform infraröd spektroskopi (FTIR). Resultaten påvisar att åldring påverkas mycket av vilket föryngringsmedel som används, vilket blev tydligt när den reologiska förmågan testades. De kemiska analyserna gav stort sett liknade resultat oberoende av bindemedel. Blandningen som innehöll RAP och mjukbitumen visade sig vara mer mottagligt för åldring jämfört med den andra blandningen som innehöll växtolja, trots att den blandningen innehåller längre halt av RAPen. Vidare visar resultaten att blandningar kan prestera likt referensmaterialet när det kommer till reologi. Från den kemiska aspekten, uppvisar alla bindemedelsmaterial liknande egenskaper. Därför kan slutsatsen att RAPen var återvunnen med framgång när växtolja och mjukbitumen användes. / In recent years there has been a lot of focus on reduction of carbon footprint and sustainable development. For the asphalt industries, a way of doing this is to use reclaimed asphalt pavement (RAP) binders. This cannot be done without any complications and therefore, the RAP binder is normally rejuvenated to compensate for its high stiffness, and other poor properties like susceptibility to low temperature cracking and fatigue damage. In this project, two different ways of using RAP binder are investigated: one vegetable oil-based rejuvenator and one soft bitumen. Using the rejuvenator and soft bitumen together with a RAP binder, two different blends were made and compared to a reference bitumen which is commonly used in Sweden. The blends were made in such a way that the penetration values were close to the reference sample. Aging tests were performed by RTFOT and PAV. The testing of the non-aged and aged binder materials was divided into two sections: rheology and chemistry. The rheology testing included softening point, needle penetration, analysis with dynamic shear rheometer (DSR) and bending beam rheometer (BBR) whereas the chemistry testing included thin layer chromatography with flame ionization detector (TLC-FID) and Fourier transform infrared spectroscopy (FTIR). The results indicated that the ageing resistance of the binder materials is affected by the type of rejuvenator used which especially affects the rheological performance. The chemical performance was almost the same in each blend. The blend containing RAP binder and soft bitumen was more susceptible to ageing compared to the other blend containing oil-based rejuvenator even though the blend contained less of the RAP binder. The results also shows that the blends can perform equal to the reference sample for a rheological point of view. From a chemical point of view, the binders, including the reference, have the same properties. Therefore, the RAP binder was successfully recycled using both a bio-oil rejuvenator and soft bitumen.

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The theoretical part of the diploma thesis recapitulates the existing literature in the field of recycling asphalt mixtures with a higher content of RAP (Reclaimed asphalt pavement). The practical part of the diploma thesis examines changes in the properties of asphalt mixtures with a higher content of RAP, due to changes in mixing time. Five mixtures have been proposed for this research. It is an asphalt mixture intended for the road abrasive layer (ACO 11+). Reference mixture "A" without RAP, with a standard mixing time of 25 seconds. Mixture "B" with 40% RAP, without rejuvenator, with an extended mixing time of 40 seconds. Mixture "C" with 40% RAP, with rejuvenator and standard mixing time. Mixture "D" with 40% RAP with rejuvenator and extended mixing time of 40 seconds. Mixture "E" with 40% RAP, with rejuvenator and extended mixing time of 55 seconds.

The diploma thesis is focused on the testing of asphalt mixtures of asphalt concrete containing reclaimed asphalt and laying of the test section. The theoretical part deals with the use of reclaimed asphalt in hot asphalt mixtures, namely the specifics of rejuvenating agents, aging and asphalt mixture. Further more information on the functional properties of asphalt mixtures and the influence of reclaimed asphalt on them is given. The practical part describes testing of mixtures of ACO 11+ and ACO 11+ with 50% reclaimed asphalt and tests on asphalt binders. In order to compare the proposed mixtures, the low thermal properties of ČSN EN 12697-46 and the stiffness modules according to ČSN EN 12697-26. In the last part of the diploma thesis the results of the measured values were compared with each other in order to determine of asfphalt recovery. From the overall test results, it can be seen that the effect of the rejuvenating agent was positive. However, the desired degree of rejuvenation has not been achieved after production.

Currently it is important to address the re-use of building materials from construction reconstructed or upgraded roads. Commonly used technologies cold and hot asphalt recycling are starting using to complement with technologies using cold asphalt mixtures with rejuvinators or softeners. This type of asphalt mixtures could be used in pavement constructions with lower traffic load. This thesis deals with the design and laboratory assessment of unbound and bound mixtures R-material and recycled concrete. This thesis is experimentally testing the possibility of using functional tests to optimize the design of asphalt mixture with 100% representation of R-material with a possible revival of asphalt emulsion with a rejuvenator.

This thesis deals with the R-material use in asphalt mixtures. In the theoretical part, different kinds of flexible pavement recycling and ways of adding R-material into asphalt mixtures are discussed. The practical part deals with asphalt layers design and manufacture, specifically for binder course ACL 16+. R-material content in the blends is 0%, 20%, 25% and 30%. EVOTHERM MA3 rejuvenator is used as additive for softening of R-material. Various mixtures are compared based on tests - resistance to permanent deformation, resistance to the effects of water and low temperature properties.

The dissertation deals with the possibilities of adding recycled asphalt pavement (RAP) to the stone mastic asphalt (SMA), which is increasingly being promoted due to its good resistance to permanent deformations and high traffic load. Thanks to the use of high-quality input materials in production, this is a valuable material source. The theoretical part describes composition of SMA mixture and problems of pavement recycling. The practical part deals with SMA 11S laboratory designs with RAP ratio of 0 to 50%. Based on these suggestions, a trial section with 17 variants was placed, which varied with the content and quality of the RAP and the used additives. All variants have been subjected to functional testing not only on mixtures but also on recovered binders. The results obtained during the dissertation were used to build a certified methodology named "Methodology of application RAP to Stone Mastic Asphalt." In conclusion, the results of the dissertation are summarized.

The diploma thesis deals with the possibility of mixing binders of the PMB RC type with a binder made of reclaimed ashalt. lists the types of asphalt binders, its production and modification are in the teoretical part. There is explained the principle of rejuvenators function, types of rejuvenators. The procedures for performing tests on asphalt binders: recovery of asphalt binder, needle penetration, softening point (ring and ball method), reversible ductility, breaking point (according to Fraass) and DSR. Individual tests are evaluated and asphalt mixtures are compared in the practical part of asphalt binder. The diploma thesis deals with the possibility of mixing binders of the PMB RC type with a binder made of reclaimed ashalt. lists the types of asphalt binders, its production and modification are in the teoretical part. There is explained the principle of rejuvenators function, types of rejuvenators. The procedures for performing tests on asphalt binders: recovery of asphalt binder, needle penetration, softening point (ring and ball method), reversible ductility, breaking point (according to Fraass) and DSR. Individual tests are evaluated and asphalt mixtures are compared in the practical part of asphalt binder.

Diploma thesis deals with the influence of various dosing of Reclaimed asphalt pavement (RAP) using modified bitumen on the properties of asphalt concrete (ACO 11+) of cemented by polymer modified bitumen, while a rejuvenating agents are added into asphalt mixtures. The theoretical part of the thesis summarizes the basic knowledge of pavement recycling, polymer modified bitumens and their reuse in asphalt mixtures. The practical part deals with laboratory tests of ACO 11+ mixtures with the RAP proportion of 0 % to 50 %. The asphalt mixtures compared are evaluated by means of the Thermal Stress Restrained Specimen Test (TSRST) and Stiffness test. The results obtained within the diploma thesis can approximate the issue of recycling of asphalt mixtures with polymer modified bitumens.