M.R. Bambach

Numerical modelling of stainless steel plates in compression

Abstract The paper describes the development of numerical models for analysing stainless steel plates in compression. Material tests on coupons cut in the longitudinal, transverse and diagonal directions are included as are the results of tests on stainless steel plates. Detailed comparisons are made between the experimental and numerical ultimate loads, load–displacement curves and load–strain curves. It is shown that excellent agreement with tests can be achieved by using the compressive stress–strain curve pertaining to the longitudinal direction. The effect of anisotropy is investigated using elastic–perfectly-plastic material models, where the anisotropic material model is based on Hill’s theory. The models indicate that the effect of anisotropy is small and that it may not be required to account for anisotropy in the modelling of stainless steel plates in compression.

Characteristics of single vehicle rollover fatalities in three Australian states (2000–2007)

An analysis of 2000-2007 single vehicle rollover fatalities in three Australian states was carried out using data from the Australian National Coroners Information System. In this paper, successive selection criteria were applied to the initial dataset to analyse:overall, rollovers accounted for 35% of all occupant fatalities in a single vehicle transport injury event. For these fatalities, the occupant was ejected or stayed contained in equal proportions. However, results showed strong disparities between the more urban and densely populated states of New South Wales and Victoria, compared to the Northern Territory in terms of crash type distribution and containment of the occupant. Differences were also found in rollover initiation, speed at initiation and number of turns. Overall, the strongest association of fatal neck/thoracic spine injuries with head injuries was found for the contained, restrained occupant. This analysis of single vehicle rollover fatalities is consistent with previous findings. It also shows that in Australia, strategies for rollover injury risk mitigation will need to take into account a broad range of characteristics to be effective.

Diving versus roof intrusion: a review of rollover injury causation

Abstract Rollover injuries are the outcome of the inability of a vehicles crashworthiness design, or lack thereof, to protect its occupants during a rollover crash. While countermeasures for injuries due to ejection are well established, there is still much debate ongoing regarding injury mechanisms of occupants contained in a vehicle during a rollover and hence countermeasures required to mitigate such injuries. This paper presents and analyzes the two apparently conflicting views of injury causation for contained occupants in rollovers that have been presented in research literature to date: diving versus roof intrusion. To analyze the validity of each of these theories, the basic physics behind the underlying concepts is investigated. Injury results from the General Motors (GM) rollover Malibu II test series are then used and reanalyzed in light of the findings presented in this paper. Results show that the most injurious events in the Malibu II tests are those where the roof structure was not strengthened. It was also concluded that more work needs to be carried out to establish acceptable injury mechanisms and associated injury criteria for future rollover crash testing protocols.

Cervical and thoracic spine injury from interactions with vehicle roofs in pure rollover crashes

Around one third of serious injuries sustained by belted, non-ejected occupants in pure rollover crashes occur to the spine. Dynamic rollover crash test methodologies have been established in Australia and the United States, with the aims of understanding injury potential in rollovers and establishing the basis of an occupant rollover protection crashworthiness test protocol that could be adopted by consumer new car assessment programmes and government regulators internationally. However, for any proposed test protocol to be effective in reducing the high trauma burden resulting from rollover crashes, appropriate anthropomorphic devices that replicate real-world injury mechanisms and biomechanical loads are required. To date, consensus regarding the combination of anthropomorphic device and neck injury criteria for rollover crash tests has not been reached. The aim of the present study is to provide new information pertaining to the nature and mechanisms of spine injury in pure rollover crashes, and to assist in the assessment of spine injury potential in rollover crash tests. Real-world spine injury cases that resulted from pure rollover crashes in the United States between 2000 and 2009 are identified, and compared with cadaver experiments under vertical load by other authors. The analysis is restricted to contained, restrained occupants that were injured from contact with the vehicle roof structure during a pure rollover, and the role of roof intrusion in creating potential for spine injury is assessed. Recommendations for assessing the potential for spine injury in rollover occupant protection crash test protocols are made.

Thoracic injuries to contained and restrained occupants in single-vehicle pure rollover crashes

Around one in three contained and restrained seriously injured occupants in single-vehicle pure rollover crashes receive a serious injury to the thorax. With dynamic rollover test protocols currently under development, there is a need to understand the nature and cause of serious thoracic injuries incurred in rollover events. This will allow decisions to be made with regards to adoption of a suitable crash test dummy and appropriate thoracic injury criteria in such protocols. Valid rollover occupant protection test protocols will lead to vehicle improvements that will reduce the high trauma burden of vehicle rollover crashes. This paper presents an analysis of contained and restrained occupants involved in single-vehicle pure rollover crashes that occurred in the United States between 2000 and 2009 (inclusive). Serious thoracic injury typology and causality are determined. A logistic regression model is developed to determine associations between the incidence of serious thoracic injury and the human, vehicle and environmental characteristics of the crashes. Recommendations are made with regards to the appropriate assessment of potential thoracic injury in dynamic rollover occupant protection crash test protocols.

Data linkage for injury surveillance and research in Australia: perils, pitfalls and potential

Objective: To outline some of the key issues for injury‐related data linkage studies in Australia and describe potential applications of data linkage for injury surveillance and research.

Head Injuries to Restrained Occupants in Single-Vehicle Pure Rollover Crashes

Objective: Studies performed previously of seat-belted occupants in real-world passenger vehicle rollover-only crashes have identified the head as one of the body regions most often seriously injured. However, there have been few studies investigating how these head injuries occur in any detail. This study aims to investigate the characteristics and patterns of head injury to seat-belted occupants in real-world rollover-only crashes and to identify possible biomechanical mechanisms responsible for head injury to aid in the development of a dynamic rollover test protocol. Methods: National Automotive Sampling System–Crashworthiness Data System (NASS-CDS) data were used to generate summary statistics and perform logistic regression analysis of restrained and contained occupants in U.S. pure trip-over rollover crashes. Specific information from selected CDS cases focused on identifying potential mechanisms and patterns of serious head injury and the rollover conditions under which the injury occurred are also presented. Results: Twenty-one percent of seriously injured occupants in pure trip-over rollovers had a serious head injury. On average, occupants seated on the far side of the rollover sustained serious head injuries more frequently and were more likely to receive injuries to the inboard side of the head than near-side occupants. Serious head injuries appear to be decoupled from serious injuries to other body regions except for a relationship found between basal skull fractures and cervical spine fractures. Serious head injuries were sustained by some occupants who had less than 15 cm of roof crush above their seated position. Conclusions: Serious brain injuries appear to occur frequently as a result of loading to the periphery of the head from contact with the roof assembly. Two mechanisms of injury for basal skull fractures in rollover crashes were identified. The injury patterns and locations of contact to the head are sensitive to the seated position of the occupant.

Injury typology of fatal motorcycle collisions with roadside barriers in Australia and New Zealand

Motorcyclists contribute significantly to road trauma around the world through the high incidence of serious injuries and fatalities. The role of roadside safety barriers in such trauma is an area of growing concern amongst motorcyclists, road authorities and road safety researchers and advocates. This paper presents a case series analysis of motorcyclists that were fatally injured following a collision with a roadside barrier during the period 2001-2006 in Australia and New Zealand. Injury profiles and severities are detailed, and associations with crash characteristics are investigated. It is shown that the thorax region had the highest incidence of injury and the highest incidence of maximum injury in fatal motorcycle-barrier crashes, followed by the head region. This is in contrast to fatal motorcycle crashes in all single- and multi-vehicle crash modes, where head injury predominates. The injury profiles of motorcyclists that slid into barriers and those that collided with barriers in the upright posture were similar. However, those that slid in were more likely to receive thorax and pelvis injuries.

Fatality risk for motorcyclists in fixed object collisions

Motorcyclists contribute significantly to road trauma around the world through the high incidence of serious injuries and fatalities. Around one fourth of motorcyclist fatalities may be attributed to collisions with fixed objects. A greater understanding of factors associated with fatalities occurring from fixed object collisions will enable safer roadway infrastructure design for motorcyclists. In this article, a multiple variable logistic regression model is developed to determine such factors, from a nationally representative weighted sample of around 30,000 single-vehicle fixed object motorcycle collisions which occurred in the United States over the 10-year period between 2000 and 2009. Additionally, a single variable logistic regression model is developed for motorcyclist fatality risk from fixed object collisions as a function of travel speed. This model may be a useful predictive tool for implementing motorcyclist safety strategies.

Risk factors associated with the severity of injury outcome for paediatric road trauma

Road trauma is one of the most common causes of injury for children. Yet risk factors associated with different levels of injury severity for childhood road trauma have not been examined in-depth. This study identifies crash and injury risk factors associated with the severity of non-fatal injury outcome for paediatric road trauma. A retrospective analysis was conducted of paediatric road trauma identified in linked police-reported and hospitalisation records during 1 January 2001 to 31 December 2011 in New South Wales (NSW), Australia. The linkage rate was 54%. Injury severity was calculated from diagnosis classifications in hospital records using the International Classification of Disease Injury Severity Score. Univariate and multi-variable logistic regression was conducted. There were 2412 car occupants, 1701 pedestrians and 612 pedal cyclists hospitalised where their hospital record linked to a police report. For car occupants, unauthorised vehicle drivers had twice the odds (OR: 2.21, 95%CI 1.47-3.34) and learner/provisional drivers had one and a half times higher odds (OR: 1.54, 95%CI 1.15-2.07) of a child car occupant sustaining a serious injury compared to a minor injury. For pedal cyclists and pedestrians, there were lower odds of a crash occurring during school commuting time and higher odds of a crash occurring during the weekend or on a dry road for children who sustained a serious versus a minor injury. Injury prevention initiatives, such as restraint and helmet use, that should reduce injury and/or crash severity are advocated.