Deliverables Rheological characteristics of new binders and their combination with binder from reclaimed asphalt - The result concerns the rheological characteristics of binders and their combination with the binder from the reclaimed asphalt. Comparisons are also performed with the rheological properties of the binders recovered from the experimental trials. The result is an important input for the future European specifications for the binders. - The output of Paramix concerning the characteristics of the combined binder (new binder + old binder from RA) is of high interest for the road authorities and contractors, in Belgium and abroad. - A lot of research in needed in this field in order to predict the performance of roads with use of reclaimed asphalt. New parameters to correct relative moisture effect on central measured deflection when comparing several data auscultation. When we are trying to evaluate the evolution of the bearing capability of the recycled pavement layers by means of the measured central deflection we have to take into account the moisture effect. The measured deflection depends on the granular layers moisture, so if we want to compare deflections with several moisture conditions its a must to correct them as they were measured with the highest moisture conditions. With the aim of estimating the granular moisture conditions while measuring, a new parameter had been developed taking into account the farthest deflection from the load plate. Correcting the moisture effect with this parameter a more accurate structural analysis can be done. New method for cold recycled mixtures design, based on its cohesion and its cracking energy and deformation The method employed for the cold mixtures design nowadays is based on tests and proceedings developed for the study of hot bituminous mixes. They are designed considering, basically, its stability, but in the case of cold recycling, the basic property to consider is the cohesion given by the emulsion to the reclaimed material. In that sense, a new methodology for the design and characterisation of these materials has been developed. It is based on the cohesion of the cold recycled materials evaluated by means of the indirect tensile test. The cohesion of the mixture is measured under dry and wet conditions, in order to evaluate, also, its resistance to the stripping, another very important parameter to characterise and to design these materials. Another parameter which is going to be considered to improve the proposed method is the tenacity (toughness) of the mixture, evaluated by means of the application of BTD test (Direct Tensile Barcelona). This test evaluates the resistance of the mixture to cracking fatigue failure in pavements. It has also been defined a new proceeding to manufacture the specimens in the laboratory which obtains specimens densities closer to the mixtures obtained at the field. Mix design procedure for hot bituminous mixtures with reclaimed asphalt One of the important steps in the rehabilitation of roads with hot reclaimed asphalt, is the design of the hot bituminous mixtures. A first step in this design procedure is the analytical design of the mixture making use of the characteristics of its constituents (new granular material, reclaimed asphalt, new binder). By means of this preliminary analytical design step, the number of experimental tests to check the basic mix characteristics against specifications and to judge its performance can be limited. Use was made of a design software Prado-win, developed earlier at BRRC and widely used in Belgium for the design of hot bituminous mixtures. Within this project this software was used and adapted for the use of mixes with reclaimed asphalt. It could be shown within this project that the so-calculated values corresponded well with the measured values on the mix composition. Hence, this analytical mix design procedure could be validated for hot mixes with reclaimed asphalt. This software is distributed by BRRC. Seminars, training courses are organized at regular time intervals and the design procedure has been presented at national and international conferences. The software is especially suitable to make a good estimate of the impact of changes in the characteristics of the RA or in the new materials. New proceeding to characterise the fatigue performance of bituminous mixtures from its breaking deformation and its fracture energy The fatigue performance is a fundamental property of the bituminous mixtures. This property defines the performance of the pavement due to fatigue cracking, considering that this is the mechanism, which produces its failure. The lower the fatigue resistance of the mixture is, the higher must be the thickness of the pavement asphalt layers to resist the same number of load applications. However, and despite its importance, this property is not considered when the mixture and its constituents are designed. The most important reason to this fact is that the determination of the fatigue performance is found out with the help of quite sophisticated tests and equipments which are more common in a laboratory or in an investigation centre than in a work laboratory. That's why the Road Laboratory of UPC has developed a new proceeding, which permits to evaluate the fatigue performance of the mixture starting from the results obtained by a direct tensile test. With the parameters determined with direct tensile tests (fracture energy, toughness, tenacity and fracture deformation) it can be evaluated the fatigue performance of the mixture in order to obtain the best composition against the fracture fatigue mechanism. Proposal of recommendations and rules summarizing the experience from the new pavement and analysis methods The idea of this result is, as a conclusion, to write a report summarising all relevant aspects that have been taken place meanwhile the three-year life of the project. One of the main goals of the project is based in the participation of all agents implied in the recycling hot/cold mixtures. The fact that the project includes from material, test and control laboratories - CEPSA-PROAS, BRRC, UPC and LGAI - to end user administrations or constructors - SNRA, GISA and COPCISA - passing through the hot and cold industrial techniques - SIM and WIRTGEN - and even considering numerical codes to simulate the behaviour of the mixtures - CIMNE and CHALMERS - makes it a interesting framework from which any result/experience should be taken in consideration. Those results, that in most of the cases, would not have been possible unless the narrow work carried out by some of the partners will be presented and summarised in a report which should be a guidelines for further research as well as a reference for those European countries with a lack of recycling mixtures knowledge. Development of improved binders for hot in-plant and cold in-situ recycling techniques Hot recycling is actually carried out in asphalt mixing plants where a percentage of reclaimed asphalt is used. The amount of reclaimed asphalt employed depends mainly on plant limitations, on mixtures design and their final requirements as well. The fresh binder used will clearly contribute to the final mixture performance. Therefore, the development of binders for hot recycling performed within PARAMIX Project has focused on obtaining and improving the structural strength as well as the fatigue behaviour of the final mixtures (two different mixtures have been assessed) so that the life period of pavements can be increased. In that sense, the effect of polymer modification or the use of renewing agents has been evaluated concluding that the renewing agents do not clearly contribute in a positive way to the final behaviour of the mixture. Nevertheless, the employ of polymer modified binders has allowed the recycling of a porous wearing course replacing it also as a SMA wearing course. Considering this type of mixture, the employ of polymer modified binders is a requirement to fulfil due to the mixture characteristics. Also as an innovation of this stage can be considered the development of a polymer modified bitumen that will allow obtaining a final High Modulus Recycled Mixture (HMM). This kind of mixture is used in order to improve the strength of the pavement layers. The objective within PARAMIX Project was focused on verifying the contribution of high modulus polymer modified binders to the improvement of structural strength and fatigue behaviour of the final recycled pavement. Cold in-situ recycling technique gives the advantage of recycling 100% of the old pavement. Nevertheless, this technique shows some drawbacks as it is the additional humidity required (in addition to the water contained in the emulsion) in order to do the compaction and coating steps. Therefore, the final cold mixture needs a curing time before being covered. This period will allow the humidity to be eliminated and in general a period of two or three weeks is a common delay. A controlled traffic circulation during this time will help the compaction of the cold recycled mixture. On the other hand, the cohesion increase of a cold recycled mixture is usually a slow process and consequently, it is necessary an immediate curing time that can last between two and six hours. The development of emulsion formulae carried out within this Project has allowed, acting on the binder and aqueous phases of the emulsions, to obtain coated surfaces of the milled material over 90% keeping them during mixture, handling and compaction processes. It has also been possible the diminishment of the additional water needed in the process, getting at the same time good cohesion behaviours. The later would contribute to a possible reduction of curing periods, which is one of the main inconveniences of this technique. The employ of polymer modified bitumens as binders of these emulsions is also a novelty within this area and it is also expected from them a great contribution to the final cohesion behaviour, strength and fatigue behaviours of the recycled mixture. The influence of polymer modification, renewing agents as well as of lower penetration grades has been evaluated. Although it is necessary to take into account that a cold recycled mixture is a mixture in evolution within time, it has been observed from Experimental Tracks that a slight better behaviour has been obtained with renewing agents. Development of an improved milling and mixing drum together with a larger mixing chamber to improve the mixing quality and influence the grain size of the recycled material Improved components for the milling and mixing process: Development of an improved milling and mixing drum together with a larger mixing chamber to improve the mixing quality and influence the grain size of the recycled material. When milling with the currently available milling drums, the milled materials grading and degree of mixing with the binding agents can be improved by changing the forward speed of the recycling machine, by changing the arrangement of the cutting tools on the milling drum and by changing the volume and exit area of the milling and mixing chamber on the recycling machine. These influence factors were tested on various milling and recycling jobs using an existing recycling machine of type Wirtgen 2200 CR. The three goals at the beginning of the project were to establish a relationship between milling machine speed and milling drum speed, to achieve a greater mixing space for the aggregate and binding agent and to achieve a greater depth of cut with the current machine. Although the machine that received these components has only been working in concrete, the factors discussed above, were successfully achieved on this particular project. There is however room for further practical research and development in this area. This subject is interesting to many contractors and consultants as it can influence the production and quality of the milled material and also the end product when recycling existing road materials. Design and construction of recycling techniques: Construction project concerning to the Spanish experimental tracks GISA elected the road where the experimental tracks have been built, according to their technical characteristics in terms of the original situation of the pavement and the requirements demanded by the technical committee. GISA has also taken care of the administrative process in order to allow the construction of the project, with the approval of the General Road Management Department of the Generalitat de Catalunya (regional Catalan Government). The reinforcement is located on a 5-kilometre two-lane track (with a particular section of three lanes along 2,3 kilometres), where 11 sub-tracks were executed: 5 with hot recycling techniques, 2 with cold recycling techniques, 2 with both hot and cold recycling techniques and 2 with conventional reinforcement. The experimental binders and mixtures were implemented in all the sub-tracks, except in the last two conventional-reinforced ones. The characterisation and dosage of the asphalt mixtures was proposed after the analysis of the deflection measurement carried out at the project road by LGAI. Performance characteristics of hot bituminous mixtures with a high percentage of reclaimed asphalt Performance aspects of bituminous mixtures with a large percentage of RA is of high interest for the road authorities and contractors. There is indeed a strong demand towards the use of a higher percentage of reclaimed asphalt. Therefore there is a strong need for research in this matter and there is a need to determine the limits of the use of RA with respect to performance or to have guidelines of how performance can be improved. Within this project BRRC concentrated mostly on the aspects of compactibility and resistance to permanent deformation (rutting). One has to keep in mind that in case of a high percentage of RA, the binder consists of very hard binder from the RA on one hand and on very soft binders on the other hand. Both new and old material are only mixed during a very short period (of the order of seconds). It is a success of this project that new binders and mixtures could be developed that lead to a good performance on site: good compaction and a very high rutting resistance. Some of the outcome of the Paramix project leading to improvements in the test methods or changes in the specifications of bituminous mixtures with RA could be incorporated in the future European standards. 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