In this paper, a real-world accident that involved a tractor-semitrailer that lost its brakes on a steep downgrade is analyzed. The crash was caused by brake loss due to massive overheating caused by inoperative brakes, driving too fast for conditions, and driving in an improper gear. The effect on brake temperatures from prior uphill and downhill stretches encountered just before the crash is considered. The crash is analyzed using a Microsoft Excel spreadsheet-based transient brake model for three sets of published brake temperature modeling methodologies and parameters: The Grade Severity Rating System developed by NHTSA (GSRS), a model developed by the University of Michigan Transportation Research Institute (UMTRI), and a model developed by Rudolf Limpert (Limpert). A fourth and different approach utilized a heavy truck simulation (HVE-SIMON) with HVE Brake Designer. The results of this analysis using the four models are compared. The Microsoft Excel spreadsheet-based transient brake model is an effective tool to better understand brake performance in real-world scenarios. It can be used by traffic safety managers, those involved with vehicle design, accident reconstructionists, and highway designers to obtain a better understanding of truck brake capabilities, the effects of out-of-service criteria and driving overloaded on brake performance, and the importance of ensuring that drivers understand how brake temperature affects brake performance. HVE Brake Designer is shown to also be an effective predictor of brake temperatures on mountain descents. When equivalent parameters for thermal mass, cooling area and diffusivity constant are input into the brake temperature models of HVE, Limpert and UMTRI, there is close agreement in the calculated temperatures over a long mountain descent. The calibration method described herein should be used to assure consistent parameters between the models.
Comparison of established heavy brake heating/cooling models with HVE brake designer in a real mountain accident
Vergleich zwischen verschiedenen mit HVE Brake Designer entwickelten Bremstemperaturmodellen bei der Analyse eines reelen Bergunfalls
2006
8 Seiten, 9 Bilder, 5 Tabellen, 9 Quellen
Aufsatz (Konferenz)
Englisch
SAE Technical Papers | 2006
|British Library Conference Proceedings | 2006
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