ANALYZING STRESSES AND FOLDS IN CAR WRECKS USING GEOLOGIC METHODS

Using techniques commonly applied in tectonic analysis, we can analyze fold patterns deformed by automobile collisions. The stresses and folds seen in car wrecks are similar to stresses and folds in rock layers caused by geologic processes.

Knowing this relationship, will the interpretation of folds in car wrecks, using techniques applied in tectonic analysis, convey the principle angle of stress? The data produced from the analysis will include interlimb angles, dip directions, axial planes and photographs.

Analysis of the data may yield answers to additional questions. Will the natural slope of the hood produce bias results? Do the stresses created during a collision dissipate and radiate from the impact area? Lastly, will patterns in the data bring about implications to the broadness of the impacter?

With the help of AAA Auto Parts, we were able to examine four cars with varying points of impact. When studying rock folds, the use of the geographic coordinate system helps find the orientation of the strike and dip direction. When studying car wrecks, however, using this geographic coordinate system does not suffice because the vehicle is not in the same frame of reference. A modified coordinate system, first suggested by Koch, M(2004), was developed to determine the orientation of the strike and dip direction. Front, right, left and back were used to orient the folds on the vehicle. A specialized protractor was developed to measure the folds using the front of the vehicle as our heading.

The results showed that analyzing the folds produced by collisions proved obvious concepts. The stresses dissipate in the opposite direction from the point of impact, and we also observe that the stresses radiate in all directions. The vehicle’s hood showed a bias with the interlimb angles produced, with the exception of cars with planar hoods - for example, the Ford Flex. The relationship of the vehicle’s height in comparison to the unknown impacter’s height possibly influences the data recorded from the hood. Although the impacter is unknown, the variation of dip directions possibly indicates the impacter’s relative broadness. With the sum of the data, the analysis identifies the principle angle of stress.