An expression defined as a man (bro) engaging in sexual relations with a woman (slampiece or broad) and once the female has performed the task of pleasuring the man, either in forms of vaginal intercourse (slayin' poon), anal penetration (hittin' that ass), or oral sex (gettin' dome); the man no longer has any productive use for the worthless broad. Thus, the man will easily dispose and discard of the woman by "tossing her to the railroad tracks." Problem solved.
One who has successfully completed this process is known as a "conductor."
Broserker: bro, did u end up nailin' that sheba last night?
BrodaciousFlow: yea man, that hoochie got railed then tossed to the tracks like a used rubber.