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Roadway and traffic characteristics for bicycling Author Janice Kirner Providelo Suely da Penha Sanches Presenter 謝博任 • Abstract • The promotion of bicycle transportation includes the provision of suitable infrastructure for cyclists. • The present paper describes research developed to define which roadway and traffic characteristics are prioritized by users and potential users in the evaluation of quality of roads for bicycling in urban areas of Brazilian medium-sized cities. • A focus group discussion identified 14 attributes representing characteristics that describe the quality of roads for bicycling in Brazilian cities. Abstract The five most important attributes, in their opinion, are: (1) lane width; (2) motor vehicle speed; (3) visibility at intersections; (4) presence of intersections; and (5) street trees (shading). Therefore, the research suggests that to promote bicycle use in Brazilian medium-sized cities, these attributes must be prioritized. Introduction The promotion of bicycling is part of the current strategy of urban planning and transport. In order to determine if a road is suitable for bicycling or not, and what improvements need to be made to increase the level of service for bicycles on specific situations, it is important to know how cyclists perceive the characteristics that define the roadway environment. Introduction A prior focus group discussion identified the following 14 characteristics as the ones that can best describe the quality of roads for cycling in Brazilian cities: 1. motor vehicle traffic volume 2. motor vehicle speed 3. signalized intersections 4. presence of heavy vehicles 5. presence of intersections Introduction 6. direction of traffic flow (one-way or two-way) 7. visibility at intersections 8. pavement condition, 9. lane width 10. driveways and side streets 11. on-street vehicle parking 12. roundabout 13. grades (slope) 14. street trees (shading) Roadway and traffic characteristics for cycling A focus group discussion was carried out in the Brazilian city of Rio Claro, in the state of Sao Paulo. The focus group was conducted with eight participants, whose profile varied among: 1. experienced bicyclists 2. participants of a local NGO related to bicycling 3. students and professors from the Department of Geography of a local University (UNESP, Rio Claro) involved in transportation planning or similar fields 4. members from the Secretary of Transportation of the local municipality. Roadway and traffic characteristics for cycling The data collected in the discussion was then analyzed through the method of Content Analysis, developed by Bardin (1995). The survey The method chosen to assess the perceptions of individuals was the application of questionnaires based on the Likert-type scale. participants also answered a series of questions about their profile: 1. gender 2. age 3. education level 4. whether or not they could ride a bicycle 5. bicycle availability at the household 6. what type of cyclist they were 7. travel motives in which the bicycle is used 8. types of infrastructure used to ride a bicycle and frequency of bicycle use. The survey The survey was conducted between March and April of 2009. A total of 451 questionnaireswere distributed in the cities of Sao Carlos and Rio Claro. The analysis was performed on 447 complete questionnaires. The survey The survey Method of Successive Intervals In this research, the Method of Successive Intervals, developed by Guilford (1975) was chosen. It is based on psychometric scales for estimation of individuals’ opinion, originally proposed by Thurstone (1927). These scales have been broadly used in fields such as applied psychology, health and marketing (Blischke et al. 1975), and also in several researches in the field of transportation (Correia and Wirasinghe 2007). Method of Successive Intervals As an example, Fig. 1 presents the observed frequencies for the attribute ‘‘presence of heavy vehicles’’. Most of the respondents (59.5%) are in category 5, which means they totally agreed with the statement, and only 2.7% are in category 1 Method of Successive Intervals Results As can be seen in Table 9, the respondents considered ‘‘lane width’’ to be the most important attribute of shared use roadways (score 1.00) followed by ‘‘motor vehicle speed’’ with score 0.87. Several published researches also identified the width of the road as a main factor in the evaluation of the shared road quality for bicycles (Sorton and Walsh 1994; Harkey et al. 1998; Epperson 1994; Landis 1994, 1996; Landis et al. 1997, 2003; Dixon 1996). Results The least important attributes were ‘‘driveways and side streets’’ (score 0.00), and ‘‘pavement condition’’ (score 0.07). Surprisingly, ‘‘motor vehicle volume’’ appeared as rather unimportant, with a score of 0.30, while in most bicycle level-of-service models, the volume of vehicles has a significant importance. Conclusions It was verified that the most important characteristic in the evaluation of quality of roads for bicycling was 1.lane width 2. followed by motor vehicle speed 3.visibility at intersections 4. presence of intersections and 5. street trees. Therefore, the research suggests that to promote bicycle in roadways of shared traffic in Brazilian medium-sized cities, these attributes must be prioritized by 1. providing larger lane width 2.reducing motor vehicle speed 3. increasing visibility at intersections 4. reducing the number of intersections and 5. increasing the number of street trees 6. to guarantee more shading on the roads. Conclusions One of the interesting findings is that, for these survey participants, the motor vehicle speed is more important than the motor vehicle volume, meaning that they are willing to ride a bicycle sharing the road with a great number of cars, if those are travelling at lower speeds, and as long as the lane is wide. Conclusions Further studies on this topic could contribute to the understanding of the opinion of users and potential users on the quality of roads for bicycling. As a suggestion, other surveys focusing different profiles of participants, or including different attributes, would be recommended.