This compression aids in preventing the frame 40 from sliding on the tie 12, and further seals {HEAD ~ the rail seat area} 18 beneath {TAIL ~ the tie pad} from any incursion of moisture 
beneath
This compression aids in preventing the frame 40 from sliding on the tie 12 , and further seals { HEAD ~ the rail seat area } 18 beneath { TAIL ~ the tie pad } from any incursion of moisture
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH