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1.
Like pedestrians, bicyclists are vulnerable road users, representing a population with a high risk of fatal and severe injuries in traffic accidents as they are unprotected during vehicle collisions. The objective of this study is to investigate the kinematics response of bicyclists and the correlation of the injury severity with vehicle impact speed. Twenty-four car–bicyclist cases with detailed information were selected for accident reconstruction using mathematical models, which was implemented in the MADYMO program. The dynamic response of bicyclists in the typical impact configuration and the correlation of head impact conditions were analyzed and discussed with respect to the head impact speed, time of head impact and impact angle of bicyclists to vehicle impact speed. Furthermore, the injury distribution of bicyclists and the risk of head injuries and fractures of lower limbs were investigated in terms of vehicle impact speed. The results indicate that wrap-around distance (WAD), head impact speed, time of head impact, head impact angle, and throw-out distance (TOD) of the bicyclists have a strong relationship with vehicle impact speed. The vehicle impact speed corresponding to a 50% probability of head AIS 2+ injuries, head AIS 3+ injuries, and lower limb fracture risk for bicyclists is 53.8 km/h, 58.9 km/h, and 41.2 km/h, respectively. A higher vehicle impact speed produces a higher injury risk to bicyclist. The results could provide background knowledge for the establishment or modification of pedestrian regulations considering bicyclist protection as well as being helpful for developing safety measures and protection devices for bicyclists.  相似文献   

2.
Information on 2558 persons treated for injuries incurred while bicycling or walking was collected from eight hospital emergency departments over approximately a one-year time period. The emergency departments represented a mix of urban and suburban/rural sites in three states--California, New York, and North Carolina. The data were collected on special survey forms and included detailed information about the location of the injury event. Results show that, overall, 70% of the reported bicycle injury events and 64% of the reported pedestrian injury events did not involve a motor vehicle. In addition, 31% of the bicyclists and 53% of the pedestrians were injured in non-roadway locations such as sidewalks, parking lots, or off-road trails. Although pedestrians and bicyclists struck by motor vehicles in the roadway were generally the most seriously injured, they represented less than a third of the reported cases. Increased knowledge of non-roadway and non-motor vehicle pedestrian and bicyclist injury events can contribute to more effective program and countermeasure development to improve pedestrian and bicyclist safety.  相似文献   

3.

Background

Bicycling related head injuries (HIs) can be severe. Helmet use reduces head injury risk; however, there are few controlled studies of the effect of helmet legislation. We conducted this study to investigate changes in HIs after bicycle helmet legislation targeting those <18 in Alberta, Canada in 2002.

Methods

Bicyclist and pedestrian (control) HI rates and HIs as a proportion of all injuries were compared for the three years (1999–2001) before and four years (2003–2006) after bicycle helmet legislation in three age groups (children: <13, adolescents: 13–17, and adults: 18+).

Results

There were 41,270 ED visits and 2782 hospitalizations for bicyclists and 9836 ED visits and 2029 hospitalizations for pedestrians (excluding the legislation year 2002). The rate of ED HIs declined for child bicyclists and child pedestrians, while the rate of non-HIs declined in adult bicyclists and child pedestrians. The rate of hospitalized HIs declined in child bicyclists and all ages of pedestrians while non-HI rates declined for child and adult pedestrians. Non-HI rates for adolescent and adult bicyclists increased. After adjusting for sex and location, the proportion of ED bicycle HIs declined by 9% (APR = 0.91; 95% CI: 0.86, 0.95) in children, was unchanged among adolescents and increased in adults (APR = 1.08; 95% CI: 1.01, 1.15). The proportion of bicycle HI related hospitalizations decreased by 30% (APR = 0.70; 95% CI: 0.55, 0.90) in children, 36% (APR = 0.64; 95% CI: 0.49, 0.84) in adolescents and 24% (APR = 0.76; 95% CI: 0.63, 0.91) in adults. There were no observed changes in the proportion of pedestrian HIs resulting in ED visits or hospitalizations.

Interpretation

Our data indicate significant declines in the proportion of child bicyclist ED HIs and child, adolescent and adult bicyclist HI hospitalizations. This is in contrast to no significant trends in the proportion of ED or hospitalized HIs among pedestrians and the unexpected increases in the proportion of ED HIs for adult bicyclists. Comparing bicyclist and pedestrian trends in the proportion of child and adolescent HIs suggests a bicycle helmet legislation effect.  相似文献   

4.
With the pressing demand of environmentally friendly personal transportation vehicles, mobility scooters become more and more popular for the short-distance transportation. Similar to pedestrians and bicyclists, scooter riders are vulnerable road users and are expected to receive severe injuries during traffic accidents. In this research, a MADYMO model of vehicle–scooter crash scenarios is numerically set up. The model of the vehicle with the scenario is validated in pedestrian–vehicle accident investigation with previous literatures in terms of throwing distance and HIC15 value. HIC15 values gained at systematic parametric studies. Injury information from various vehicle crashing speeds (i.e. from 10 m/s to 24 m/s), angles (i.e. from 0 to 360°), scooter's speeds (i.e. from 0 m/s to 4 m/s), contact positions (i.e. left, middle and right bumper positions) are extracted, analyzed and then compared with those from widely studied pedestrian–vehicle and bicycle–vehicle accidents. Results show that the ESS provides better impact protection for the riders. Riding ESS would not increase the risk higher than walking at the same impact conditions in terms of head injury. The responsible reasons should be the smaller friction coefficient between the wheel-road than the heel-road interactions, different body gestures leading to different contact positions, forces and timing. Results may shed lights upon the future research of mobility scooter safety analysis and also the safety design guidance for the scooters.  相似文献   

5.
In road traffic collisions, pedestrian injuries and fatalities account for approximately 11% and 20% of casualties in the USA and the EU, respectively. In many less motorised countries, the majority of victims are pedestrians. The significant influences of vehicle speed, pedestrian speed and pedestrian gait on pedestrian post-impact kinematics have been qualitatively noted in the literature, but there has been no quantitative approach to this problem. In this paper, the MADYMO MultiBody (MB) pedestrian model is used to analyse the influences of vehicle speed, pedestrian speed and pedestrian gait on the transverse translation of the pedestrian's head, head rotation about the vertical head axis and head impact velocity. Transverse translation has implications for injury severity because of variations in local vehicle stiffness. Head rotation is related to pedestrian stance at impact, which is known to affect the kinematics of a collision. Increased head impact velocity results in greater head injury severity. The results show that transverse translation of the head relative to the primary contact location of the pedestrian on the vehicle decreases with increasing vehicle speed and increases linearly with increasing pedestrian speed. Head rotation decreases with increasing vehicle speed and increases linearly with increasing pedestrian speed, but these variations are small. The range of head rotation values decreases with increasing vehicle speed. Head impact velocity increases linearly with vehicle speed and is largely independent of pedestrian speed. Transverse translation, head rotation and head impact velocity all vary cyclically with gait in clearly definable patterns.  相似文献   

6.
A large number of pedestrian fatalities were reported in China since the 1990s, however the exposure of pedestrians in public traffic has never been measured quantitatively using in-depth accident data. This study aimed to investigate the association between the impact speed and risk of pedestrian casualties in passenger vehicle collisions based on real-world accident cases in China. The cases were selected from a database of in-depth investigation of vehicle accidents in Changsha-IVAC. The sampling criteria were defined as (1) the accident was a frontal impact that occurred between 2003 and 2009; (2) the pedestrian age was above 14; (3) the injury according to the Abbreviated Injury Scale (AIS) was 1+; (4) the accident involved passenger cars, SUVs, or MPVs; and (5) the vehicle impact speed can be determined. The selected IVAC data set, which included 104 pedestrian accident cases, was weighted based on the national traffic accident data. The logistical regression models of the risks for pedestrian fatalities and AIS 3+ injuries were developed in terms of vehicle impact speed using the unweighted and weighted data sets. A multiple logistic regression model on the risk of pedestrian AIS 3+ injury was developed considering the age and impact speed as two variables. It was found that the risk of pedestrian fatality is 26% at 50 km/h, 50% at 58 km/h, and 82% at 70 km/h. At an impact speed of 80 km/h, the pedestrian rarely survives. The weighted risk curves indicated that the risks of pedestrian fatality and injury in China were higher than that in other high-income countries, whereas the risks of pedestrian casualty was lower than in these countries 30 years ago. The findings could have a contribution to better understanding of the exposures of pedestrians in urban traffic in China, and provide background knowledge for the development of strategies for pedestrian protection.  相似文献   

7.
The aim of this study was to aid the optimisation of future, vehicle based, pedestrian injury countermeasures. The German In-Depth Accident Study (GIDAS) database was queried for pedestrians impacted by the front of a passenger car or van. A total of 1030 cases from 1998 to 2008 were studied including 161 severely (AIS3+) injured pedestrians. Considering the severe injuries, the most frequent injury mechanisms were “leg-to-front end”, “head-to-windscreen area”, “chest-to-bonnet area”, and “chest-to-windscreen area”. For children, a “head-to-bonnet area” impact was the second most common source of injury. With safety systems targeting these five injury mechanisms, 73% (95% confidence interval [CI], 65–81%) of the severely injured pedestrians would be provided protection from all of their vehicle-induced severe injuries. Omitting the windscreen area, this figure is decreased to 44% (CI, 36–53%). Furthermore, 31% of the surviving pedestrians were estimated to sustain a permanent medical impairment at any level. For more severe impairment, head was the dominating body region. The study shows that when developing countermeasures for the windscreen area to mitigate head injuries, attention should be paid to the structural parts of the windscreen area with a special focus on brain injuries. Finally, the incidence and risk of severe injury were derived as functions of impact speed for different body regions and injury sources.  相似文献   

8.
The objective of this study was to determine whether the bicycle safety helmet legislation in California, enacted in 1994, was associated with statistically significant reductions in head injuries among bicyclists aged 17 years and under who were subjected to the law. The study used 44,069 patient discharge cases from all public hospitals in California, from 1991 through 2000, and a case-control design to make direct comparisons between those subjected to the law (Youth) and those who were not (Adult) across the pre- and post-legislation periods. An aggregate data analysis approach and a pooled disaggregate data fitting technique using multinomial logit models were applied. The legislation was found to be associated with a reduction of 18.2% (99% confidence interval: 11.5-24.3%) in the proportion of traumatic brain injuries (Head-TBI) among Youth bicyclists. The proportions of other head, face, and neck injuries were not significantly changed across the pre- and post-legislation periods in this age group but there was a corresponding increase of 9% (5-13%) in the proportion of all other injuries. On the other hand, there was no statistically significant change in the proportions of injury outcomes for Adult bicyclists. The youngest riders, aged 0-9 years, had the greatest decrease in the proportion of Head-TBI. The reduction was the same for motor vehicle and non-motor-vehicle-related incidents. The bicycle safety helmet legislation was associated with a decrease in the likelihood of Head-TBI for non-urban residents but not for urbanites, for males but not for females, and for Whites, Asians, and Hispanics, but not Blacks and others.  相似文献   

9.
Police reports were compared to the information provided by a hospital monitoring system for children under 15 years old injured as pedestrians and bicyclists by moving motor vehicles in Orange County, California. The analysis was limited to identifying caveats in the police report database. Underreporting by police was conservatively estimated at 20% for pedestrians and 10% for bicyclists. Comparison of the pedestrian databases suggested underreporting by police of incidents involving 0-4-year-olds, nontraffic incidents, incidents in which the vehicle was backing up, and cases not involving a child crossing a street. Comparison of the bicyclist databases indicated an underreporting by police of nontraffic cases. These caveats, in part, are related to police agency reporting requirements. The police injury severity scale was found to correlate poorly with a scale based on medical diagnoses, and substantial underreporting by police of serious injuries was demonstrated. We suggest that utilization of police injury severity scales be limited to categories of fatal, injured, and not injured (when available).  相似文献   

10.
As automobile transportation continues to increase around the world, bicyclists, pedestrians, and motorcyclists, also known as vulnerable road users (VRUs), will become more susceptible to traffic crashes, especially in countries where traffic laws are poorly enforced. Many countries, however, are employing innovative strategies to ensure that road users can more safely navigate the urban landscape. While bicyclists and motorcyclists are important road users, this paper will focus on pedestrian crash problems and solutions. Pedestrians are most at risk in urban areas due in part to the large amount of pedestrian and vehicle activity in urban areas. With this in mind, designing safe, accessible, and comprehensive facilities for pedestrians is vital to reducing pedestrian crashes. This paper will provide some insight into the magnitude of the pedestrian crash problem around the world, and will offer some lessons learned from several countries, particularly in Europe and the U.S., for improving pedestrian safety. Beginning with pedestrian safety statistics at the global, regional, and national levels, this paper will address potential countermeasures and strategies for improving pedestrian safety from an international perspective.  相似文献   

11.
Accident data have shown that in pedestrian accidents with high-fronted vehicles (SUVs and vans) the risk of pedestrian head injuries from the contact with the ground is higher than with low-fronted vehicles (passenger cars). However, the reasons for this remain poorly understood. This paper addresses this question using multibody modelling to investigate the influence of vehicle front height and shape in pedestrian accidents on the mechanism of impact with the ground and on head ground impact speed. To this end, a set of 648 pedestrian/vehicle crash simulations was carried out using the MADYMO multibody simulation software. Impacts were simulated with six vehicle types at three impact speeds (20, 30, 40 km/h) and three pedestrian types (50th % male, 5th % female, and 6-year-old child) at six different initial stance configurations, stationary and walking at 1.4 m/s.  相似文献   

12.
This paper proposes a methodology to quantify the safety benefits of an active hood lift system (AHLS) for protecting pedestrians. AHLS works by lifting up the hood of a vehicle to obtain the space to absorb the impact energy before the pedestrian's head hits the hood in pedestrian–vehicle collision. The safety benefit is defined as the number of pedestrian lives saved by the AHLS. Both actual accident data analysis and simulation experiments were conducted to develop a probabilistic pedestrian fatality model based on the head injury criteria (HIC). Then, the fatality model was further applied to estimate the safety benefit. Analysis results revealed that the 95% confidence interval of the number of pedestrian lives saved by the AHLS was between 32.8 and 83.6 pedestrians. It is believed that the proposed methodology could be further applied in evaluating other vehicular technologies for traffic safety. In addition, the outcomes of this study would be effectively utilized in establishing relevant traffic safety policies.  相似文献   

13.
In the United States, passenger vehicles are shifting from a fleet populated primarily by cars to a fleet dominated by light trucks and vans (LTVs). Because light trucks are heavier, stiffer, and geometrically more blunt than passenger cars, they pose a dramatically different type of threat to pedestrians. This paper investigates the effect of striking vehicle type on pedestrian fatalities and injuries. The analysis incorporates three major sources of data, the Fatality Analysis Reporting System (FARS), the General Estimates System (GES), and the Pedestrian Crash Data Study (PCDS). The paper presents and compares pedestrian impact risk factors for sport utility vehicles, pickup trucks, vans, and cars as developed from analyses of US accident statistics. Pedestrians are found to have a two to three times greater likelihood of dying when struck by an LTV than when struck by a car. Examination of pedestrian injury distributions reveals that, given an impact speed, the probability of serious head and thoracic injury is substantially greater when the striking vehicle is an LTV rather than a car.  相似文献   

14.
Pedestrian injuries and vehicle type in Maryland, 1995-1999   总被引:2,自引:0,他引:2  
Pedestrian deaths constitute the second largest category of motor vehicle deaths in the US. The present study examined how pedestrian injury is associated with vehicle type, while controlling for vehicle weight and speed.Police, trauma registry, and autopsy data were linked for injured pedestrians. Logistic regression analyses were performed to control for vehicle weight and speed. Outcomes included pedestrian mortality, injury severity score, and injuries to specific body regions.Compared to conventional cars, pedestrians hit by sport utility vehicles and pick-up trucks were more likely to have higher injury severity scores (odds ratio=1.48; 95% confidence interval: 1.18-1.87) and to die (odds ratio=1.72; 95% confidence interval: 1.31-2.28). These relationships diminished when vehicle weight and speed were controlled for. At lower speeds, pedestrians struck by sport utility vehicles, pick-up trucks, and vans were approximately two times as likely to have traumatic brain, thoracic, and abdominal injuries; at higher speeds, there was no such association.The overall increased danger sport utility vehicles and pick-up trucks present to pedestrians may be explained by larger vehicle masses and faster speeds. At slower speeds being hit by sport utility vehicles, and pick-up trucks, and vans resulted in specific injuries, indicating that vehicle design may contribute to different injury patterns.  相似文献   

15.
New York state enacted the first safety belt use law in the United States in 1984. We evaluated the effects of the law by reviewing all hospital admissions from motor vehicle crashes in Monroe County, New York. We compared admissions for the 18 months prior to the effective date of the law with those for the 18 months after the law became effective. Police accident reports and hospital records were coupled and intensively reviewed. Motorcyclists, pedestrians, and bicyclists (bicycle collisions with motor vehicles) became controls for the study. Seat belt usage was determined from police and hospital record information. Analysis of the data revealed that safety belt use among patients hospitalized because of motor vehicle accidents increased from 11.2% before the law became effective to 53% after the law became effective. Hospital admissions decreased 11.9% among motor vehicle occupants and increased 2.6% among controls. The ISS decreased from 16.01 to 14.55 for motor vehicle occupants and increased' from 14.77 to 15.11 among controls. Among subjects all injuries decreased except injuries of the spine and abdomen, which increased in the postlaw period.  相似文献   

16.
With the expansion of bicycle usage and limited funding and/or space for segregated pedestrian and bicycle paths, there is a need for traffic, road design and local government engineers to decide if it is more appropriate for space to be shared between either cyclists and pedestrians, or between cars and cyclists, and what restrictions need to be applied in such circumstances. To provide knowledge to aid engineers and policy makers in making these decisions, this study explored death and morbidity data for the state of New South Wales, Australia to examine rates and severity of injury arising from collisions between pedestrians and cyclists, and between cyclists and motor vehicles (MVs).An analysis of the severity of hospitalised injuries was conducted using International Classification of Diseases, Version 10, Australian Modification (ICD-10-AM) diagnosis-based Injury Severity Score (ICISS) and the Disability Adjusted Life Year (DALY) was used to measure burden of injury arising from collisions resulting in death or hospitalisation. The greatest burden of injury in NSW, for the studied collision mechanisms, is for cyclists who are injured in collisions with motor vehicles. Collisions between cyclists and pedestrians also result in significant injuries. For all collision mechanisms, the odds of serious injury on admission are greater for the elderly than for those in other age groups. The significant burden of injury arising from collisions of cyclists and MVs needs to be addressed. However in the absence of appropriate controls, increasing the opportunity for conflict between cyclists and pedestrians (through an increase in shared spaces for these users) may shift the burden of injury from cyclists to pedestrians, in particular, older pedestrians.  相似文献   

17.
A surveillance system in the Emergency Department of a level 1 pediatric trauma center previously identified minor bicycle crashes as a cause of serious child abdominal injury. A discordancy exists between the apparently minor circumstances and serious injuries sustained by child bicyclists who impact bicycle handlebars. The objective of this work was to redesign the bicycle handlebar to reduce the forces transmitted to the child's abdomen during an impact with the handlebars. A retractable handlebar consisting of a spring–mass–damper system was designed to retract and absorb the majority of energy at impact (Patent pending). Because the child remains in contact with the bar after impact, the retracting system also includes a mechanism to damp the outward motion of the handlebar. This prototype will reduce the forces at impact by 50% in a collision similar to those discussed above. A unique methodology of translating research findings into product design produced a novel handlebar that absorbs significant energy that otherwise would be transferred to the child's abdomen when impacting the handlebar.  相似文献   

18.
Bicycling at night is more dangerous than in the daytime and poor conspicuity is likely to be a contributing factor. The use of reflective markings on a pedestrian's major joints to facilitate the perception of biological motion has been shown to greatly enhance pedestrian conspicuity at night, but few corresponding data exist for bicyclists. Twelve younger and twelve older participants drove around a closed-road circuit at night and indicated when they first recognized a bicyclist who wore black clothing either alone, or together with a reflective bicycling vest, or a vest plus ankle and knee reflectors. The bicyclist pedalled in place on a bicycle that had either a static or flashing light, or no light on the handlebars. Bicyclist clothing significantly affected conspicuity; drivers responded to bicyclists wearing the vest plus ankle and knee reflectors at significantly longer distances than when the bicyclist wore the vest alone or black clothing without a vest. Older drivers responded to bicyclists less often and at shorter distances than younger drivers. The presence of a bicycle light, whether static or flashing, did not enhance the conspicuity of the bicyclist; this may result in bicyclists who use a bicycle light being overconfident of their own conspicuity at night. The implications of our findings are that ankle and knee markings are a simple and very effective approach for enhancing bicyclist conspicuity at night.  相似文献   

19.
This study identifies and compares the significant factors affecting pedestrian crash injury severity at signalized and unsignalized intersections. The factors explored include geometric predictors (e.g., presence and type of crosswalk and presence of pedestrian refuge area), traffic predictors (e.g., annual average daily traffic (AADT), speed limit, and percentage of trucks), road user variables (e.g., pedestrian age and pedestrian maneuver before crash), environmental predictors (e.g., weather and lighting conditions), and vehicle-related predictors (e.g., vehicle type). The analysis was conducted using the mixed logit model, which allows the parameter estimates to randomly vary across the observations. The study used three years of pedestrian crash data from Florida. Police reports were reviewed in detail to have a better understanding of how each pedestrian crash occurred. Additionally, information that is unavailable in the crash records, such as at-fault road user and pedestrian maneuver, was collected. At signalized intersections, higher AADT, speed limit, and percentage of trucks; very old pedestrians; at-fault pedestrians; rainy weather; and dark lighting condition were associated with higher pedestrian severity risk. For example, a one-percent higher truck percentage increases the probability of severe injuries by 1.37%. A one-mile-per-hour higher speed limit increases the probability of severe injuries by 1.22%. At unsignalized intersections, pedestrian walking along roadway, middle and very old pedestrians, at-fault pedestrians, vans, dark lighting condition, and higher speed limit were associated with higher pedestrian severity risk. On the other hand, standard crosswalks were associated with 1.36% reduction in pedestrian severe injuries. Several countermeasures to reduce pedestrian injury severity are recommended.  相似文献   

20.
The head is the body region that most frequently incurs fatal and serious injuries of cyclists in collisions against vehicles. Many research studies investigated helmet effectiveness in preventing head injuries using accident data. In this study, the impact attenuation characteristics of three Japanese child bicycle helmets were examined experimentally in impact tests into a concrete surface and a vehicle. A pedestrian adult headform with and without a Japanese child bicycle helmet was dropped onto a concrete surface and then propelled into a vehicle at 35 km/h in various locations such as the bonnet, roof header, windshield and A-pillar. Accelerations were measured and head injury criterion (HIC) calculated. In the drop tests using the adult headform onto a concrete surface from the height of 1.5 m, the HIC for a headform without a child helmet was 6325, and was reduced by around 80% when a child helmet was fitted to the headform. In the impact tests, where the headform was fired into the vehicle at 35 km/h at various locations on a car, the computed acceleration based HIC varied depending on the vehicle impact locations. The HIC was reduced by 10–38% for impacts headforms with a child helmet when the impact was onto a bonnet-top and roof header although the HIC was already less than 1000 in impacts with the headform without a child helmet. Similarly, for impacts into the windshield (where a cyclist’s head is most frequently impacted), the HIC using the adult headform without a child helmet was 122; whereas when the adult headform was used with a child helmet, a higher HIC value of more than 850 was recorded. But again, the HIC values are below 1000. In impacts into the A-pillar, the HIC was 4816 for a headform without a child helmet and was reduced by 18–38% for a headform with a child helmet depending on the type of Japanese child helmet used. The tests demonstrated that Japanese child helmets are effective in reducing accelerations and HIC in a drop test using an adult headform onto a relatively rigid hard surface, i.e., simulating a road surface or concrete path. However, when the impact tests are into softer surfaces, the child helmet’s capacity to decrease accelerations is accordingly reduced. Impacts into the windshield, while below the critical HIC value of 1000, indicated higher HIC values for a headform with a child helmet compared to an adult headform without a child helmet. The unpredictable nature of the results indicates further research work is required to assess how representative the stiffness of an adult headform is when compared to an actual head.  相似文献   

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