2013 Session: 558

• Experience of Electric Bicycle Users in the Area of Davis-Sacramento, California
  Abstract: For this project, we interviewed 27 electric bicycle (e-bike) users in the Sacramento/Davis, California area. We found three significant benefits relative to conventional bicycles: functionality (speed, acceleration, ability to carry cargo), adherence to green values, and enabling bicycle transportation to be feasible for more people, and more trips. E-bikes are faster than conventional bicycles, so e-bike users can cut down commute time and ride more frequently than if they were using a conventional bicycle. The ease of acceleration makes obeying stop signs and riding uphill less onerous and provides e-bike users with more confidence interacting with automobiles. E-bikes also provide an option for green transportation for people who can’t or don’t wish to participate in conventional bicycling. Finally, they enable people with certain disabilities, illness, symptoms of aging, or time constraint, to continue to bike. The barriers to the expansion of e-bike ridership are high cost, heavy weight, lack of safe infrastructure (unsafe roads and communities, and lack of emergency charging), policy (separated bike paths are not open to e-bikes) . However, those barriers could be overcome with government and business interventions, if expansion of e-bike mode share is a desired outcome.
  Authors: Gordon, Elizabeth; Shao, Zhenying; Xing, Yan; Wang, Yunshi; Handy, Susan L.
  Authors: Gordon, Elizabeth; Shao, Zhenying; Xing, Yan; Wang, Yunshi; Handy, Susan L.
  Year: 2013
  Document Type: Paper
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-1709
• Analysis of Safety and Environmental Effects of Introducing Microcars into Traffic Flows
  Abstract: This study analyses the characteristics of traffic flow when microcars are present. A two-lane cellular automata model is formulated to simulate a mixed traffic flow consisting of conventional passenger cars and microcars. Segments of urban highway and arterial road, both with two lanes and measuring 400 m in length, are simulated, including an intersection delay with a signal cycle at the midpoint of the latter. Traffic flows with different ratios of microcars are investigated in the simulation. Four aspects of traffic conditions are calculated: the number of lane changes, the number of decelerations, and the speed variation for analysis of safety and energy consumption as a measure of environmental impact. The simulation results provide several insights into the safety and environmental impact of introducing microcars. They suggest that microcars have no effect or a positive effect on safety when measured in terms of the number of decelerations and speed variation, both on highways and arterial roads. However, safety situation as measured in terms of lane changes is reduced. Vehicle emission will obviously decrease with the introduction of microcars, especially on highways. This is also true of arterial roads in free-stream flow, but the superiority of microcar diminishes in congested flow.
  Authors: Mu, Rui; Yamamoto, Toshiyuki
  Authors: Mu, Rui; Yamamoto, Toshiyuki
  Year: 2013
  Document Type: Paper
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-1480
• Modeling Passing Events in Mixed Bicycle Traffic Using Cellular Automata
  Abstract: The primary objective of this study is to use the cellular automata method to model the characteristics of bicycle passing events in mixed bicycle traffic on separated bicycle paths. The mixed bicycle traffic is composed of two types of bicycles which are the conventional bicycle and electric bicycle. The number of passing events as well as the characteristics of mixed bicycle traffic was investigated in the field at 8 physically separated bicycle paths in China. Then a cellular automata model was calibrated using the field data to simulate the passing events in the mixed bicycle traffic. The results showed that the cellular automata model can well simulate the features of bicycle passing events. The simulation results are consistent with field observations. An increase in the ratio of electric bicycles will not significantly increase the number of passing events. But electric bicycles have a large contribution to the passing events in the mixed bicycle traffic. Electric bicycles showed to have a stronger anti-inference ability than conventional bicycles especially in the traffic condition of high flow rate. Findings of this study can improve the performance of simulation techniques to reflect the actual characteristics of mixed bicycle traffic.
  Authors: Zhao, De; Wang, Wei; Li, Chenyang; Li, Zhibin; Fu, Pengming; Hu, Xiaojian
  Authors: Zhao, De; Wang, Wei; Li, Chenyang; Li, Zhibin; Fu, Pengming; Hu, Xiaojian
  Year: 2013
  Document Type: Paper
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-1490
• Comparative Analysis of Effects of E-bikes and Bicycles on Safety of Signalized Intersections Using Traffic Conflict Technique
  Abstract: In this study, a comparative analysis was conducted to compare the risk-taking behaviors of the riders of e-biker and bicycles and their effects on safety of signalized intersections. Data were collected at fourteen signalized intersections in the city of Kunming in China. It was found that 10.31% of the e-bikers have committed at least one of the identified risky behaviors when crossing intersections, which was 1.42 times as large as that of the bikers (7.28%). Traffic conflicts technique was used to estimate the safety effects of e-bikes and bicycles. The conflicts observed in the field were divided into fifteen types. The majority of the observed conflicts were caused by the risky behaviors of the drivers of automobiles. The predominant cause was that the drivers of automobiles did not yield to the right-of-way of e-bikes/bicycles, which accounted for 76.1% of the conflicts involving e-bikes and 74.4% of the conflicts involving bicycles. About 13.8% of the conflicts were caused by the risky behaviors of e-bikers, which was significantly higher than those caused by the bicycle riders (9.2%), but significantly lower than those caused by the drivers of automobiles (77%). Red-light running was the leading cause for the conflicts in which the e-bikes were at-fault. The conflict rates associated with e-bikes and bicycles were compared. It was found that for all the conflict types the conflict rates for e-bikes were significantly higher than those for the bicycles. The conflict prediction model developed in this study showed that the presence of e-bikes significantly affected the total number of conflicts at a signalized intersection. The results of elasticity analysis showed that 1% increase in the proportion of e-bikes would increase the expected number of conflicts between automobiles and e-bikes/bicycles by 0.11%.
  Authors: Bai, Lu; Liu, Pan
  Authors: Bai, Lu; Liu, Pan
  Year: 2013
  Document Type: Paper
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-1605
• The Built Environment and Household Electric Bike Ownership:Insights from Zhongshan Metropolitan Area, China
  Abstract: Planners and policy-makers have recognized the effects of the built environment on the vehicle ownership and use. Among voluminous literature, few studies were found that examined how the built environment is associated to the household E-bike ownership. This study explored the relationship between the built environment and household electric bike ownership in the Chinese context, based on the data collected in Zhongshan Metropolitan Area. The E-bike choice models suggest that household measures dominate the number of household E-bikes, but also detect a relationship between several built environment attributes and the household E-bike ownership. All else being equal, denser and higher-mixed land-use development, more connective transportation linkages, commercial and job connections are related to lower household E-bike ownership. Households located in the urban neighborhoods tend to own fewer E-bikes, compared to suburban or rural households. The availability of competitive transportation modes is strongly related to the likelihood of owning E-bikes. The findings suggest policy-makers to consider built environment attributes in the policy-making of E-bike ownership and set differentiated policies in different areas according to the variations of the built environment. It is also suggested to integrate the E-bike ownership policies with the ownership policies of competitive modes and also policies related to public transportation service improvement.
  Authors: Zhang, Yi; Li, Yuan; Yang, Xiaoguang; Li, Chaoyang
  Authors: Zhang, Yi; Li, Yuan; Yang, Xiaoguang; Li, Chaoyang
  Year: 2013
  Document Type: Paper
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-5297
  Practice-Ready: Yes
• Analysis of Safety and Environmental Effects of Introducing Microcars into Traffic Flows
  Authors: Mu, Rui
  Authors: Mu, Rui
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-1480
• Modeling Passing Events in Mixed Bicycle Traffic Using Cellular Automata
  Authors: Zhao, De
  Authors: Zhao, De
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-1490
• The Built Environment and Household Electric Bike Ownership: Insights from Zhongshan Metropolitan Area, China
  Authors: Zhang, Yi
  Authors: Zhang, Yi
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Pedestrians and Bicyclists; Safety and Human Factors; Vehicles and Equipment
  Session: 558
  Paper Number: 13-5297