With its massive life, is Battering ram good in using them as folder/meatshield for ballistae and catapult assault force?

What about if use archers in place of ballistae/catapult? Say, 50k rams with 74k archers plus the standard layers?

9 millions food per hour for 90k ram is a pain to upkeep. That is 72 lv5 npc worth of food per day.