In 2014, 32,675 deaths were recorded in vehicle crashes within the United States. Out of these, 51% of the fatalities occurred in rural highways compared to 49% in urban highways. No specific crash data are available ...In 2014, 32,675 deaths were recorded in vehicle crashes within the United States. Out of these, 51% of the fatalities occurred in rural highways compared to 49% in urban highways. No specific crash data are available for the built-up areas along rural highways. Due to high fatalities in rural highways, it is important to identify the factors that cause the vehicle crashes. The main objective of this study is to determine the factors associated with se- verities of crashes that occurred in built-up areas along the rural highways of Nevada. Those factors could aid in making informed decisions while setting up speed zones in these built-up areas. Using descriptive statistics and binary logistic regression model, 337 crashes that occurred in 11 towns along the rural highways from 2002 to 2010 were analyzed. The results showed that more crashes occurred during favorable driving conditions, e.g., 87% crashes on dry roads and 70% crashes in clear weather. The binary logistic regression model showed that crashes occurred from midnight until 4 a.m. were 58.3% likely to be injury crashes rather than property damage only crashes, when other factors were kept at their mean values. Crashes on weekdays were three times more likely to be injury crashes than that occurred on weekends. When other factors were kept at their mean value, crashes involving motorcycles had an 80.2% probability of being injury crashes. Speeding was found to be 17 times more responsible for injury crashes than mechanical defects of the vehicle. As a result of this study, the Nevada Department of Transportation now can take various steps to improve public safety, including steps to reduce speeding and encourage the use of helmets for motorcycle riders.展开更多
Speeding is often considered as one of the major reasons of traffic crashes. As a result, State Departments of Transportations （DOTs） receive requests from communities to decrease speed limits in towns along rural h...Speeding is often considered as one of the major reasons of traffic crashes. As a result, State Departments of Transportations （DOTs） receive requests from communities to decrease speed limits in towns along rural highways. Such requests, coupled with the lack of proper manuals, have forced state DOTs to reduce the speed limits. A proper speed-zone manual is required to establish consistent speed zones across a state. This paper reviewed the literature on speed, crashes, enforcement techniques, and speed-zone manuals. A nationwide survey was conducted to identify various factors affecting the decisions of speed zones establishing. This paper identified best practices based on the literature review and expert opinions, and proposed a comprehensive framework for a speed-zone manual. The Nevada DOT traffic engineers were also interviewed during this research to incorpo- rate their opinions in the framework. The framework provided in this paper has six phases. They are; 1） speed-zone identification; 2） speed-limit determination; 3） transition-zone detailed design; 4） speed-zone approval; 5） speed-limit enforcement; and 6） follow-up study. Relevant studies, and manuals corresponding to each phases were presented in this paper. This framework is useful for NDOT, other state DOTs within the U.S., and transportation agencies worldwide that haven＇t had speed zone manuals currently to develop a proper speed-zone manual.展开更多
基金Nevada Department of Transportation(NDOT)for funding the studyprovided under grant#P255-11-803 by NDOT
文摘In 2014, 32,675 deaths were recorded in vehicle crashes within the United States. Out of these, 51% of the fatalities occurred in rural highways compared to 49% in urban highways. No specific crash data are available for the built-up areas along rural highways. Due to high fatalities in rural highways, it is important to identify the factors that cause the vehicle crashes. The main objective of this study is to determine the factors associated with se- verities of crashes that occurred in built-up areas along the rural highways of Nevada. Those factors could aid in making informed decisions while setting up speed zones in these built-up areas. Using descriptive statistics and binary logistic regression model, 337 crashes that occurred in 11 towns along the rural highways from 2002 to 2010 were analyzed. The results showed that more crashes occurred during favorable driving conditions, e.g., 87% crashes on dry roads and 70% crashes in clear weather. The binary logistic regression model showed that crashes occurred from midnight until 4 a.m. were 58.3% likely to be injury crashes rather than property damage only crashes, when other factors were kept at their mean values. Crashes on weekdays were three times more likely to be injury crashes than that occurred on weekends. When other factors were kept at their mean value, crashes involving motorcycles had an 80.2% probability of being injury crashes. Speeding was found to be 17 times more responsible for injury crashes than mechanical defects of the vehicle. As a result of this study, the Nevada Department of Transportation now can take various steps to improve public safety, including steps to reduce speeding and encourage the use of helmets for motorcycle riders.
基金Nevada Department of Transportation(NDOT)for funding and guidance for this studyThe funding of this research was provided under Grant #P255-11-803 by NDOT
文摘Speeding is often considered as one of the major reasons of traffic crashes. As a result, State Departments of Transportations （DOTs） receive requests from communities to decrease speed limits in towns along rural highways. Such requests, coupled with the lack of proper manuals, have forced state DOTs to reduce the speed limits. A proper speed-zone manual is required to establish consistent speed zones across a state. This paper reviewed the literature on speed, crashes, enforcement techniques, and speed-zone manuals. A nationwide survey was conducted to identify various factors affecting the decisions of speed zones establishing. This paper identified best practices based on the literature review and expert opinions, and proposed a comprehensive framework for a speed-zone manual. The Nevada DOT traffic engineers were also interviewed during this research to incorpo- rate their opinions in the framework. The framework provided in this paper has six phases. They are; 1） speed-zone identification; 2） speed-limit determination; 3） transition-zone detailed design; 4） speed-zone approval; 5） speed-limit enforcement; and 6） follow-up study. Relevant studies, and manuals corresponding to each phases were presented in this paper. This framework is useful for NDOT, other state DOTs within the U.S., and transportation agencies worldwide that haven＇t had speed zone manuals currently to develop a proper speed-zone manual.
