A Review and Analysis of the Performance of Laminated Side Glazing in Rollover Accidents

Advanced glazing has been investigated as a means by which to reduce occupant ejection in rollover accidents. However, most testing on these advanced glazing materials has not effectively captured the occupant kinematics typically seen in actual rollover accidents, and as a result, passing these tests does not ensure occupant retention. While current work has attempted to characterize the dynamic (impact) and static (push-out) material properties necessary for understanding the containment performance of advanced glazing, most testing has consisted of single impacts. Rollover accidents typically include multiple impacts and potentially long duration centrifugal forces on the side glazing. As such, there is little test and/or simulation data to support the theory that advanced glazing would substantially reduce the risk of occupant ejection in rollover accidents. The risk of head injury due to occupant impacts may not be significantly different between tempered and laminated glazing, but higher neck forces have generally been reported for laminated glazing. The laceration potential of laminated glazing may also be significant. This paper reviews the existing literature and testing in the area of automotive glazing materials, with specific emphasis on the containment potential of advanced glazing. We also present an analysis of the centrifugal forces on side window glazing due to occupant contact during rollover accidents. These forces most likely exceed the containment potential of laminated glazing.