Characterization of the pressure field over a stepped spillway in Roller Compacted Concrete dams

摘要

In the Laboratory of Scale Models of the Hydraulics, Maritime and Environmental Engineering Department of the UPC a physical model of a stepped spillway has been assembled. In this paper, the pressure field over a stepped spillway is characterized, providing information about the maximum and minimum pressures registered over the spillway in order to evaluate these hydrodynamic loads with the resistance of the concrete and the cavitation risk. For all the tested discharges occurs a fully developed skimming flow regime over the chute. This flow regime introduces several characteristics to the pressure field that are focused from two different aspects: the first one shows the behavior of the pressure over the symmetry center of the horizontal faces of the steps along the whole chute, downstream the point of inception of air entrainment; and the second one points out the characterization of pressure profiles over the horizontal and vertical faces of the steps.