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Für das Forschungsvorhaben wurden Performance-Kennwerte in den Phasen der Asphaltmischgutkonzeption, Asphaltmischgutproduktion und nach dem Asphalteinbau an 21 Baumaßnahmen für die Asphaltdeck-, -binder- und -tragschicht systematisch erfasst und ausgewertet. Als Performance-Kennwerte dienten die Ergebnisse aus den Prüfungen zur Steifigkeit, zum Widerstand gegen Kälterissbildung, zum Ermüdungs- und Verformungs-widerstand sowie zur Griffigkeitsentwicklung. Die Untersuchungen lieferten wichtige Erkenntnisse und Tendenzen bei einzelnen Performance-Kennwerten, die bereits jetzt für zwei methodische Ansätze zur Festlegung künftiger vertragsrelevanter Anforderungen genutzt werden konnten: Einerseits wurde ein Vorschlag für eine spezifische Kategorisierung von Performance-Kennwerten innerhalb der europäischen Normung aufgezeigt, andererseits konnte mit Hilfe multipler linearer Regressionsanalysen ein möglicher Weg zur Abschätzung von Performance-Kenngrößen der fertigen Schicht aus der Erstprüfung aufgezeigt werden, sodass Anforderungswerte vorab definiert werden können. Zudem zeigte sich, dass, auch wenn im Wesentlichen die Ergebnisse der konventionellen Asphaltkontrollprüfungen die Anforderungen der ZTV Asphalt erfüllen, es nicht sichergestellt ist, dass Nutzungsdauern von mindestens 30 Jahren erreicht werden können. Dies resultiert im Wesentlichen aus den Unterschieden der Performance-Kenngrößen der drei Phasen, vor allem der Ermüdungsversuche. Deshalb wurden für die Modifikation des Sicherheitskonzeptes für die rechnerische Dimensionierung zwei Ansätze vorgestellt. Es erscheint aber zwingend erforderlich, dass durch weitere Untersuchungen die erstellte Datenbank ergänzt wird. Zudem sollten die im Projekt untersuchten Strecken einer weiteren Beobachtung unterzogen werden, um den Prozess der Alterung erfassen zu können. Damit kann auch eine Validierung des Dimensionierungsverfahrens erfolgen.
Since the compulsory use of child restraints for children up to 5 years of age was introduced in 2000, restraint use among younger children has increased significantly. However, the observed rate of child restraint use plateaus at around 50%, and apparently little spillover effect has been found for older children who are not covered by the law. This report examines the restraint use patterns for children who were injured in cars in relation to driver and child passenger characteristics. Univariate and multivariate analyses were conducted to describe the association between the outcome measure (the proper use of restraints for children) and relevant variables. Better ways for parents and caregivers to improve the use of restraints for children are also discussed.
While cyclists and pedestrians are known to be at significant risk for severe injuries when exposed to road traffic accidents (RTAs) involving trucks, little is known about RTA injury risk for truck drivers. The objective of this study is to analyze the injury severity in truck drivers following RTAs. Between 1999 and 2008 the Hannover Medical School Accident Research Unit prospectively documented 43,000 RTAs involving 582 trucks. Injury severity including the abbreviated injury scale (AIS) and the maximum abbreviated injury scale (MAIS) were analyzed. Technical parameters (e.g. delta-v, direction of impact), the location of accident, and its dependency on the road type were also taken into consideration. The results show that the safety of truck drivers is assured by their vehicles, the consequence being that the risk of becoming injured is likely to be low. However, the legs especially are at high risk for severe injuries during RTAs. This probability increases in the instance of a collision with another truck. Nevertheless, in RTAs involving trucks and regular passenger vehicles, the other party is in higher risk of injury.
Safety of light goods vehicles - findings from the German joint project of BASt, DEKRA, UDV and VDA
(2011)
Light goods vehicles (LGVs) are an important part of the vehicle fleet, providing a vital component in the European transportation system. On the other hand, LGVs are in the focus of public discussion regarding road safety. In order to analyse the accident situation of LGVs in an objective manner, Federal Highway Research Institute (BASt), VDA, DEKRA and German Insurers Accident Research (UDV) launched a joint project. The aim of this project, which will be finished by mid of 2011, is to identify reasonable measures which will further improve the safety of LGVs. For the first time, these partners jointly together conducted a research project and put together their know-how in accident research. Analyses are based on real-life accident data from the GIDAS database, the Accident Database of UDV (UDB), the DEKRA database and national statistics. The findings deliver answers to questions within the arena of future legislative actions and consumer protection activities. The analyses of databases cover areas of primary and secondary safety of LGVs with a special focus on advanced driver assistance systems (ADAS), driver behaviour as well as partner and occupant protection. Key figures from national statistics are used to highlight hotspots of accidents of LGVs in Germany. Finally, the proposed countermeasures are assessed regarding their potential effectiveness. Amongst others, the results show that the accident situation of LGVs is very similar to that of passenger cars. Noteworthy variations could be found in collisions with pedestrians, at reversing and regarding accident causes. Occupant safety of LGVs is on a higher level compared to cars. Results indicate that seatbelt use is on a significantly lower level compared to cars. This leads to higher-than-average injury risk for unbelted LGV occupants. When it comes to partner protection, there are problems with compatibility at LGVs. For car occupants there is a very high injury risk when colliding with a LGV. It indicates that higher passive safety test standards for LGVs would be counterproductive if they further increase stiffness of LGVs. The analysis of LGV-pedestrian accidents shows that pedestrian kinematic differs significantly from car-pedestrian accidents. At this point, existing pedestrian related test standards developed for cars cannot be adopted to LGVs. When it comes to active safety, ESC proved its effectiveness once again. Beyond that, rear view cameras, advanced emergency braking systems and lane departure warning systems show a safety potential, too. In addition to any technical countermeasures previously discussed, the importance of the driver behavior and attitude regarding the accident risk was investigated. In order to develop successful actions it is important to understand the main target population. In the case of LGV especially the crafts business and smaller companies are the major contributors the safety issue.
This work aims at bringing evidence for mass incompatibility in frontal impact for cars built according to the UNECE R94 regulation. French national injury accidents database census for years 2005 to 2008 were used for the analysis. The heterogeneity of frontal self-protection among cars of different masses is investigated, as well as the partner protection parameter offered by these cars. The last part of the analysis deals with the estimation of the benefit, in terms of fatal and severe injuries avoided, if crashworthiness was harmonized for the whole fleet of vehicle. This calculation is done for France and is extended to all Europe.
In most of developed countries, the progress made in passive safety during the last three decades allowed to drastically reduce the number of killed and severely injured especially for occupants of passenger cars. This reduction is mainly observed for frontal impacts for which the AIS3+ injuries has been reduced about 52% for drivers and 38% for front passengers. The stiffening of the cars' structure coupled with the generalization of airbags and the improvement of the seatbelt restraint (load limiter, pretension, etc.) allowed to protect vital body regions such as head, neck and thorax. However, the abdomen did not take advantage with so much success of this progress. The objective of this study is to draw up an inventory on the abdominal injuries of the belted car occupants involved in frontal impact, to present adapted counter-measures and to assess their potential effectiveness. In the first part the stakes corresponding to the abdominal injuries will be defined according to types of impact, seat location, occupants' age and type of injured organs. Then, we shall focus on the abdominal injury risk curves for adults involved in frontal impact and on the comparisons of the average risks according to the seat location. In the second part we will list counter-measures and we shall calculate their effectiveness. The method of case control will be used in order to estimate odds ratio, comparing two samples, given by occupants having or not having the studied safety system. For this study, two type of data sources are used: national road injured accident census and retrospective in-depth accident data collection. Abdominal injuries are mainly observed in frontal impact (52%). Fatal or severe abdominal occupant- injuries are observed at least in 27% of cases, ranking this body region as the most injured just after the thorax (51%). In spite of a twice lower occupation rate in the back seats compared to the front seats, the number of persons sustaining abdominal injuries at the rear place is higher than in the front place. In recent cars, the risk of having a serious or fatal abdominal injury in a frontal impact is 1.6% for the driver, 3.6% for the front passenger and 6.3% for the rear occupants. The most frequently hurt organs are the small intestine (17%), the spleen (16%) and the liver (13%). The most common countermeasures have a good efficiency in the reduction of the abdominal injuries for the adults: the stiffness of the structure of the seats allows decreasing the abdominal injury risk from 54% (driver) to 60% (front occupant), the seatbelt pretensioners decrease also this risk from 90% (driver) to 83% (front passenger).
In Germany averagely two million traffic accidents happen each year and emergency medical services are called to more than 400 000 patients. Even though this number is decreasing continuously (due to improvements in the fields of vehicle safety, road construction, and accident prevention) every case is yet a challenge for the rescuers and requires improvements in emergency medicine as well. Especially during diagnostics right at the accident scene, there are only limited instruments available to gain the necessary knowledge of the injuries suffered, to come to essential decisions about treatment or transport. To provide an additional diagnostic aid by scouting and estimating the situation, a software-tool calculating the likeliness of the most frequent severe injuries (AIS 3-6) of front occupants in passenger cars has been developed to deliver this necessary information about particular accident scenarios. To achieve this, logistic likelihood functions have been calculated in a multivariate regression analysis analysing all AIS 3+ injuries in the GIDAS database of the years 1999-2006 that happened more than four times
To elucidate the risk of pedestrians, bicycle and motorbike users, data of two accident research units from 1999 to 2014 were analysed in regard to demographic data, collision details, preclinical and clinical data using SPSS. 14.295 injured vulnerable road users were included. 92 out of 3610 pedestrians ("P", 2.5%), 90 out of 8307 bicyclists ("B", 1.1%) and 115 out of 4094 motorcycle users ("M", 2.8%) were diagnosed with spinal fractures. Thoracic fractures were most frequent ahead of lumbar and cervical fractures. Car collisions were most frequent mechanism (68, 62 and 36%). MAIS was 3.8, 2.8 and 3.2 for P, B and A with ISS 32, 16 and 23. AIS-head was 2.2, 1.3 and 1.5). Vulnerable road users are at significant risk for spine fractures. These are often associated with severe additional injuries, e.g. the head and a very high overall trauma severity (polytrauma).
The bicyclist accidents were analyzed to get better understanding of the occurrences and frequency of the accidents, injury distributions, as well as correlation of injury severity/outcomes with engineering and human factors in two different countries of China and Germany. The accident cases that occurred from 2001 to 2006 were collected from IVAC database in Changsha and GIDAS database in Hannover. Based on specified sampling criteria, 1,570 bicyclist cases were selected from IVAC database in Changsha, and 1806 cases were collected from Hannover, documented in GIDAS database. Statistical analyses were carried out by using these selected data. The results from the statistical analysis are presented and discussed in this study.
In Germany, in-depth accident investigations are carried out in the Hannover area since 1973. In 1999 a second region was added with surveys in Dresden and the surrounding area. Internationally, the acronym GIDAS (German In-Depth Accident Study) is commonly used for these surveys. Compared to many other countries, the sample sizes of the GIDAS surveys are much larger. The goal is to collect 1.000 accidents involving personal injuries per year and region. Data collection takes place by using a sampling procedure, which can be interpreted as a two-stage process with time intervals as primary units and accidents as secondary units. An important question is, to what extend these samples are representative for the target population from which they are drawn. Analyses show, for example, that accidents with persons killed or seriously injured are overrepresented in the samples compared to accidents with slightly injured persons. This means, that these data are subject to biases due to uncontrolled variation of sample inclusion probability. Therefore, appropriate weighting and expansion methods have to be applied in order to adjust or correct for these biases. The contribution describes the statistical and methodological principles underlying the GIDAS surveys with respect to sampling procedure, data collection and expansion. In addition, some suggestions regarding potential improvements of study design are made from a methodological point of view.