Bolt Overkill
This clip angle at the ceiling detail shows bolts with a diameter of 2-3/4" that are to fit into 13/16" diameter holes! These bolts attach a channel piece to the clip angle.
Even bolts for bridges rarely exceed 1" diameter! Large bolts are generally for things like offshore drilling structures, securing nuclear power station reactors, etc. and typically require a hydraulic wrench to install or remove.
The detail also shows anchor rods with the same diameter of 2-3/4". The anchor rod attaches the clip angle to the concrete slab above. A little bit of an overkill, we think.