Rib fractures are the most frequent types of AIS3+ chest
injuries and constitute a good indication of severity. However, the
behavior of the rib cage is not well documented, and though chest
external measurements are often provided in the literature, the
strains of the ribs themselves during a crash remain unknown.
In order to address this issue, a test protocol was developed,
where the ribs of 8 PMHS were equipped with up to 96 strain gauges.
In a first series of 3 tests, the subjects were seated upright and
their chests were loaded by a 23.4 kg impactor propelled at 4.3 m/s
in 0° (pure frontal), 60° (oblique) and 90° (pure lateral)
directions. In a second series of 3 tests, the subjects were loaded
by the deployment of an unfolded airbag in the same 3 directions.
Finally, a third series of 2 tests was performed with airbags at
different distances from the subjects, in a pure lateral
direction.
This paper presents the results of the tests and an analysis of
the strain patterns. The differences between a pure frontal, a pure
lateral and an oblique loading are explored. The airbag loading is
compared to impactor loading and the severity effect is described.
Finally, the time and location of the rib fractures are analyzed as
a function of the test configuration.