OpenRail Designer has a command to place sleepers.
Actually (2021 R1) the main purpose is for visualization.
It is a "block" of cells to improve performances. You can't access individual sleeper and use your own cell.
You want to do more right now ?
Let's have a look on a simple script with GC. Yes simple.
V2 | Changed to avoid using track plane centerline. The centerline is only used to locate cells along. The height of the sleepers is determined from left and right rails only (3D middle between left and right rails). | PopulateSleepersFromExcel_NoNeedOfTrackPlaneCL_2023.gct |
I exported the script from transaction editor, where you can import in a new DGN file.