I have looked at used railroad ties and all the ones i found are not any more trustworthy-I want this to last another 50 years +. I do have a front loader but will mostly be renting a material lift so i can reach across the Bridge without driving on it until the decking is on. I have contacted a rail road tie manf. and they will only sell non treated ties to private individuals. I would go the saw mill route but still need to know the joist size and spacing to support the 5000 pounds.
As for using more steal it would be too expensive.
