Impact in Railway Bridges.

Discussion: Historical load effects on fatigue of metallic railway bridges

“…A value of 0•08 is typical for steel bridges with a span of 20 m or more, and 0•11 for 11 m spans. The effects on the bridge can be estimated conservatively by assuming that the driving wheels are spinning while stationary at the mid-span of the bridge, as has been justified by Inglis (1932). Table 6 shows the number of blows (N) and magnification factor (α) for each locomotive type considered by the authors.…”