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The European Union is promoting a circular economy in which waste management plays an essential role. Although many studies focusing on the use of recycled materials in the manufacture of asphalt mixtures for roads have been developed, studies related to the use of recycled materials for the construction of bike lanes are scarce. In this context, the main objective of this research is to explore the behaviour of asphalt mixtures with high replacement rates of recycled materials—reclaimed asphalt pavement (RAP) and ceramic waste—by natural aggregates for the construction of bike lanes. A total of six types of asphalt mixtures were designed by combining the content of the recycled materials and natural aggregates, with replacement rates ranging from 50% to 100%. The asphalt mixtures were characterized by determining the bulk and maximum density; the void content in the mixture; and the aggregate, stability, and deformation. In conclusion, the mixture C50R50, which consists of a full replacement of natural fine and coarse aggregates by 50% ceramic waste aggregate and 50% RAP, is proposed as the most appropriate sustainable solution. In this way, the use of this asphalt mixture allows for boosting the use of recycled aggregates as well as minimizing the consumption of virgin bitumen due to its residual bitumen content. Compared to the reference asphalt mixture consisting of 100% of natural aggregates, C50R50 is a more open mixture, with higher void content and somewhat more brittleness. Even so, the mixture C50R50 could be good enough for use in low traffic roads.

The condition of the road infrastructure in rural areas is precarious in developing countries and it is common to find roads built using materials such as concrete and rarely with flexible pavement. This study proposes the use of ceramic waste as aggregates in percentages of 30% and 35% in semi-dense asphalt mixtures prepared according to the standards of the National Road Institute in Colombia. Marshall tests of susceptibility, deformation and dynamic modules were performed, finding that 30% replacements showed the best behavior for low traffic roads.

The use of micromobility vehicles is considerably growing in cities worldwide. As a result, crashes involving these vehicles are also increasing, with single-bicycle crashes accounting for a significant percentage. In most infrastructure-related crashes, the road surface was slippery. In this context, the study of pavement skid resistance is crucial to improve micromobility safety. In this research, the British pendulum tester was used to test the skid resistance of 5 different types of pavements on 17 bike lane locations in Valencia (Spain). Additionally, micromobility users’ speed was collected to analyse users’ behaviour. The results showed that asphalt, concrete, and rough painted tile pavements had the greatest skid resistance, whereas painted cobble and smooth painted tile pavements presented poor skid resistance. These values were compared with the limits set by the few guidelines that includes skid resistance thresholds. Moreover, skid resistance variability was also studied, with asphalt pavement being the most homogeneous. Based on the results of the research, several recommendations are proposed for the pavement to be used in the micromobility facility according to its typology. To this end, the investigatory level of skid resistance and the minimum braking distance required were also defined for each type of pavement and bike lane. The findings of this study contribute to the consideration of micromobility safety from the construction stage to the pavement management.

[EN] Mobility patterns and lifestyles have changed in recent years in cities worldwide, thanks to the strong rise in modes of travel commonly referred to as micromobility. In this context, e-scooters have experienced a great rise globally which has led to an increase of crashes involving this type of micromobility vehicle in urban areas. Thus, there is a need to study e-scooter users¿ behaviour and their interaction with cyclists. This research aimed at characterizing the meeting manoeuvre between micromobility users along diverse typologies of two-way bicycle track by using an in-strumented e-scooter. As a result, bicycle tracks having concrete or vegetated curb presented lower clearance distance (¿0.8 m) than those without edge elements (>1 m), with no statistically signif-icant differences found between the interaction with bicycles and e-scooters. Additionally, an online questionnaire was proposed to assess users¿ perceived risk during the meeting manoeuvre, concluding that micromobility users feel safer and more comfortable riding on pavements away from parked or moving motorized traffic, and on protected bicycle tracks., FundingThis research is part of the research project PID2019-111744RB-I00, funded by MCIN/AEI/10.13039/501100011033.