Active ship intercepting method

The invention discloses an active ship intercepting method, which is characterized in that image surveillance systems are mounted on the two external sides of bridge guardrails; and ship intercept devices are respectively mounted on the two sides of non-navigable span portion of a bridge. When a ship deviates from voyage route to enter set intercepting barrier start areas, the image surveillance systems transmit enabled instructions to a control system which controls intercepting barriers to erect on the water surface, the ship strikes the intercepting barriers which hold a stem of the ship, the ship drives the intercepting barriers to move together to the bridge, the intercepting barriers are separated from supporting rods under the driving of the ship, and pulls iron chains connected with the intercepting barriers to move, and the iron chains pull heavy blocks in the submarine sludge to move, accordingly, dragging resistance to the ship is produced, and effective interception of the ship to strike the bridge is achieved. The active ship intercepting method has the advantages that under the action of the dragging resistance of the intercepting barriers, the ship to strike the bridge can gradually reduce the sailing speed till the moving stops, so that the ship is prevented from being close to or striking the bridge and safety of the bridge and the ship is guaranteed.