It's usually stored in bunkers with a concrete floor and side walls. The transfer trucks back up to the bunker and dump the silage, then large tractors push it up while at the same time compacting it. There are plenty of YT videos on the process.
To : osudairy, I know you read #1 video, While they where taken down the 3 silos on the farm, they too where taking down the old barns and they destroyed the hen / chicken barns with the house that was there since 1940 and it was a beautiful old house and it was sad to see it go. They destroyed all of them in one day, they had each destruction crew for the house, the 4 barns, the silos and a destruction crew to take down the chicken house that held 70 chickens and they all came down on the same day? never saw so many tractors and alot of dump trucks?