The bump of a boat into a gate-structure dam: An unusual risk scenario

摘要

The possibility of the bump of a boat against the dam structure was experienced at Isoia Serafini dam, the largest gate-structure dam in Italy, sited on the Po river near the town of Cremona. A large barge broke moorings about 40 km upstream of the dam site and started to float adrift toward the dam driven by the river flood. To face the possible impact against the dam an emergency action plan was immediately activated. Three central gates were completely opened, so as to produce a drugging stream in the central part of the river to drive the boat across one of the opened gates. The drugging effect was effective and successful. The barge passed through the dam without any impact and damage to the structures. After the event, numerical analyses were carried out to evaluate the severity of a possible bump into a gate. The results showed that the gate is able to absorb the kinetic energy of the barge motion, by mostly dissipating it in plastic deformation process. Large permanent displacements may be expected in the gate, but the supporting devices of the gate should not experience significant permanent deformations.