Water hammer in a bottom sluice

Conclusions

• 1. In the case of damage of the supporting devices and consequent falling, gates at the downstream sides of bottom sluices are subjected to hydrodynamic impact loading, which exceeds by a large factor (several times) not only the actual load, but also the design load for the given case. This results in immediate destruction of the gate.

• 2. The water hammer phase t_p=0.097≈0.1 sec corresponds to a vibration≈b 1/10=10 Hz, which is very close to the natural frequency of a gate having the same dimensions, in water [2]. Under these conditions, there is the possibility of initiation of a self-oscillatory regimen, which may lead to quick falling of the gate on the sill.

• 3. Strengthening the construction of the gate in the case under consideration would be pointless, since the falling gate could destroy the sluice walls, which are a part of the powerhouse.

• 4. Placement of the gates at the downstream end of very long bottom sluices may be allowed only in the case of highly reliable construction of the hooks and spreader beams, intended to prevent the gates from falling on their sills.