Limit State Design Method for PC Crossties withstanding Impact Wheel Load
Hajime WAKUI, Hiroyuki OKUDA, Hiromi INOUE
From the viewpoint of a limit state design method for PC crossties, experiments
and analyses were carried out on crack characteristics in serviceability limit state,
life evaluation in fatigue limit state and safety factor assessments in ultimate
limit state under impact loading. It is preferable to increase the decompression
moment by 30 percent more for the unbonded post-tensioned type, than for the
pre-tensioned type. It is important to assume an appropriate load distribution
curve to evaluate its fatigue life accurately. It is also necessary to take into
consideration the loading rate effects on material properties to assess impact
bending capacity. Through these studies, a new design method, composed of impact
wheel load, dynamic response and limit state design, is proposed in order to
rationalize and improve PC crosstie design.