In Figure 2, the vertical line represents the Code
of Practice maximum wheel impact force of 230kN.
Although the heavy haul rail networks from which
the data came are not part of the defined interstate
network, it’s clear that in normal operation very
large impact forces can occur and excessively
exceed the Code of Practice specification (for rolling
stock operation and testing) [11]. The frequency of
high impact wheel forces in the histogram columns
of Figure 2 lies along the sloping, dashed straight
line, which means the distribution would appear as a