Hmmm… I see there is a yellow plane/mesh below your tracks. I wonder what it looks like either without that geometry, or if that geometry was textured.
Although that effect is probably coming just from the shadowed bits - if you brighten up the vertical angles with something in the emissive channel (small value, too much and it would look like they would be glowing) maybe that will lessen the effect.
Will these always be used only on a completely flat surface? (Curving up/down in the context of a spline based mesh might lessen this optical illusion)
There’s also a Level of Detail system that will change the mesh depending on how far away it is, so authoring an asset (Maybe that uses a texture instead of meshes for ties/sleepers) could be a path forward.