First World War methods against one-ton naval mines

How could late-1910s naval architects protect ships against one-ton or larger mines?

Deep subdivision, torpedo bulges, redundant longitudinal strength, and buoyant filling can limit flooding, though a close blast may still break the ship's back.

A one-ton or larger mine would remain a severe structural threat even after extensive protection. Subdivision and bulges are proposed alongside multiple keels to support the hull. Corking means packing part of the hull with buoyant cork; it is distinct from caulking the outside of the hull. Cork traps air and is described as difficult, though possible, to ignite. HMS Belfast supplies the warning example: a ship may stay afloat yet suffer a broken back and require major repairs in harbour.