Experimental Results and Analysis on Dynamic Loading Characteristics of PC Crossties
Hiroyuki OKUDA, Hajime WAKUI
Drop-weight experiments and FEM analyses on ballasted tracks using PC crossties
were carried out. PC crossties have dynamic loading characteristics, in which the
crosstie bending moment per unit impact wheel load at its rail-seat section has a
peak of some 2 times that for the unit static wheel load for around 1.5 milli-second
duration. This peak is considered to be due to the resonance effect in relation to
both natural frequencies of PC crossties and duration of the impact wheel load,
as well as the rail-pad stiffness increase. The dynamic loading characteristics
are effectively irrespective of ballast support conditions. As a result of these
studies, design bending moments under impact wheel load have been determined for
the rail-seat section and the midsection.