Inflatable Dams

An inflatable dam provides an inexpensive and simple device for controlling the water level in a river, canal, or reservoir. It can operate under hydrodynamic conditions satisfactorily when the overflow is not high. Calculations and measurements show that the periphery of the dam and the length of the base depend largely on the inside pressure. Observations show that the water-inflated dam vibrates less than the air-inflated dam. A trip wire reduces the vibration provided the nappe is fully aerated. Nappe breakers are required when the width of the dam is large. Coefficients of discharge and variations of inside pressure with the overflow have been determined experimentally for four different shapes of the dam. It has been shown that the inside pressure increases linearly with the increase of the overflow.