There are some adhesives on the market that will hold shoes on light horses somewhat, but not on the big guys. I think we need to address your problem, which is that the nails are causing your Percherons' hooves to crack. Oftentimes farriers will use nails too large for the foot when shoeing draft horses. This tends to split the walls. Constant washing of horses will cause their feet to have the natural oils flushed away and will cause the horse's feet to dry out and crack or split.
Hoof dressings can sometimes be of a benefit towards keeping the hoof wall flexible yet strong.
Hoof dressings are most beneficial when they are applied to the coronet and bulbs of the heel and massaged. This massaging should consist of at least 3 minutes per foot. I know that this seems extreme, but you are asking what can be done to save your horses' feet. This is one of these things. The horse's diet should be given serious consideration.