Citation

Owings RP, Cantor C. Transp. Res. Rec. 1976; 594: 39-44.

Copyright

(Copyright © 1976, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

The impact of an automobile with a breakaway support for a sign or luminaire can be divided into three phases. By using simplifying assumptions, one can determine the contributions to change in vehicle momentum by each phase. The first phase involves the crushing of the automobile with negligible motion of the support. The second phase considers the contribution change in vehicle momentum by base fracture. The third phase considers the contribution to change in vehicle momentum by the acceleration of the pole. The results of this analysis are that vehicle change in momentum can be approximated by an equation that has provided valuable insight into the effect of vehicle stiffness, breakaway force level, base fracture energy, pole inertial properties, and vehicle impact speed on change in vehicle momentum. This knowledge has facilitated the subsequent development of practical laboratory acceptance test criteria to promote safer sign and luminaire supports.