Collision speed estimation using a single normalised crush depth-impact speed characteristic.

Theoretical consideration of the energy absorption properties of structures shows that the specific energy absorption is related to the normalised crush depth and to a stress/density parameter. Examination of the crush characteristics of the car population shows that the mean stress/density parameter of the car population in frontal crush is independent of car size. On this basis regression is carried out. Using data from nine staged frontal car to car collisions the generalised specific energy absorption representation is compared with CRASH3 and with Prasad's individual car reformulation.