Drag factors for metal on concrete and sand?

Topics related to Vehicle Specifications, Vehicle Acceleration Tests, Vehicle Braking Tests
MSI
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Drag factors for metal on concrete and sand?

Post by MSI »

Q: References with Drag factors for metal on concrete (or a vehicle sliding on concrete or sand)?

A: Here's a starting set we posted In response to question on tumble number in the forum
  • Chapter 20 in text, "Fundamentals of Traffic Crash Reconstruction", deals with rollover crashes.
    In that chapter, they report on Warner's SAE Paper 830162 "Friction Applications in Accident Reconstruction " in which he lists drag factors for vehicles sliding on the side.
    These values are: (Pg 714)
    • Concrete: 0.30 to 0.40
    • Asphalt: 0.40
    • Gravel: 0.50 to 0.70
    • Dry Grass: 0.50
    They also present deceleration in a rollover from several sources: (Pg 714)
    • Hight: 0.40 to 0.65
    • Orlowski: 0.36 to 0.61
    • Altman: 0.48 (avg)
    • Bratten: 0.50 (avg)
    In addition are scatter plots of both roll distance v number of rolls and rollover speed v number of rolls.
    They also discuss caveats in the use of these analyses. (Pgs 712-713)
    is a reference to Warner SAE paper 83
Also see Friction Tests on Contaminated Surfaces which included effects of sand on asphalt.

We will search for more data and please, if you come across any reference/data let us know!