The impact of a moving load speed on the dynamic overload of beams,
assuming that the track of the load has no unevenness, is examined.
First the problem of a visco-elastic beam on a Winkler foundation
subjected to a force moving at a constant speed will be solved. Using
the Bubnov-Galerkin method, the deflections of the beam, and then the
bending moments and shear forces will be determined. The solution of the
problem will be obtained both for the case of a forced vibration and the
case of a free vibration after the moving force has left the beam. Using
these solutions, dynamic amplification factors will be determined for
the deflections, bending moments, and shear forces, which are different
for the two cases.
The magnitude of the amplification factors increases and decreases
alternately as a function of the speed. In the case of a single force on
a beam, the dynamic overloads are limited, and do not exceed 60%. There
is no resonance phenomenon in the beam subjected to the single moving
force. The dynamic amplification factors determined in this way can be
used as correction coefficients when designing engineering structures
subjected to moving loads by static methods.