There is a need to move society in a sustainable direction. One way to contribute to thismove is to change to more sustainable transport modes, such as cycling. To increase cycling, theinfrastructure is important, and good quality cycle paths are needed. However, little is known aboutthe degradation of cycle paths. This paper aims to investigate what modes of pavement distressare found on municipal cycle paths in Sweden, and what probable mechanisms lie behind suchdistress; these are determined based on questions from a state-of-practice survey, interviews, and aliterature review. The main findings are that the most commonly stated distress modes are surfaceunevenness followed by longitudinal cracks, and the most commonly stated causes of distress areageing, followed by structural interventions, and roots and vegetation. The results also show that forseveral distress modes, there are probable connections with climatic factors such as temperature andmoisture, as well as with the population size of the urban areas. Objective data are needed regardingtraffic load and the climatic factors that affect cycle paths, along with information on their structuraldesign, to better understand their degradation.

Cyclists' riding comfort, related to pavement texture and unevenness, has not been thourougly investigated, partly due to the lack of condition assessment methods specifically adapted to the speed and space limits on cycle paths. Metrics that better describe the perceived comfort of cyclists, rather than that of car users, are needed. In this paper a novel method, the Bicycle Measurement Trailer (BMT), is proposed to bridge this gap. Eight different cycle path surface types have been assessed with regards to pavement texture and for four of these surfaces the longitudinal evenness was assessed. The accuracy and repeatability of the BMT were evaluated. Finally, five different metrics (Dynamic Comfort Index, Evenness Coefficient, 0.5 m Straight Edge, International Roughness Index and Root Mean Square), were calculated from the collected data and assessed. The main findings suggest that the BMT has a high accuracy at normal and high cycling speeds and a high level of repeatability at normal cycling speed. The surfaces could be ranked according to texture, and the evenness was successfully analysed. In conclusion, the BMT could be a valuable tool to assess the cycle path surface condition in relation to bicycle riding comfort.

A recurrent challenge on cycle paths are edge cracks, which affect the traffic safety and accessibility of cyclists and produce high maintenance costs. Being both structurally thinner and narrower structures than roads, the cycle paths are extra prone to this problem. A few passages of heavy vehicles in unfavourable conditions might be enough to break the edge. The load-bearing capacity of eight municipal cycle paths in Linköping, Sweden, were assessed by falling weight deflectometer (FWD) and light falling weight deflectometer (LWD) measurements during a year-long cycle. A set of alternative Deflection Bowl Parameters (DBPs), better adapted to the structural design of cycle paths, were suggested and evaluated. The results of the FWD measurements showed that these suggested DBPs are a promising approach to evaluate the load-bearing capacity of cycle paths. From the results of the LWD measurements, it was found that the load-bearing capacity varies considerably with lateral position. The conclusion is that it might be more fruitful to measure the load-bearing capacity by LWD close to the edge, rather than the traditional approach of FWD measurements along the centre line of the cycle path.

Assuring sufficient structural stability of cycle paths is important to avoid distress. Being thin andnarrow structures, they are highly susceptible to edge cracking by passings of heavy vehicles. Twoimportant factors that affect distress are lack of lateral support at the edge and increased moisturecontent in the unbound granular materials. Three full-scale instrumented cycle path structures withdifferent structural design were constructed in a concrete pit at a test facility. Response measurementswere conducted with a falling weight deflectometer, a light weight deflectometer, and light, standardand heavy maintenance vehicles at three different groundwater table scenarios. The results confirmreduced load-bearing capacity close to the edge, and at an increased groundwater table. In general, larger transverse tensile strains can also be expected in the asphalt layer close to the edge.