First, you need to import the alembic file using the File menu, Merge, import as Ornatrix Alembic. This will create a Hair Object with a BakedHair modifier with the alembic file.

Second, add the Animation Cache modifier to the Hair Object and load the alembic file there to get the animation(if there is any). 

Jeordanis Figuereo (Product Designer. EPHERE Inc.)