TURBULENT PRESSURE-FLUCTUATIONS UNDER HYDRAULIC JUMPS

New experimental evidence on the statistical structure of turbulent pressure fluctuations at the bottom of hydraulic jumps is brought in this paper in view of its relevance on stability of the linings in stilling basins. Maximum values and the structures of temporal and spatia correlation of the anisotropic field of fluctuating pressures are described. Pressures are measured in the zones of the jump where the uplift load produced on the slabs is maximum for a 5 divided-by 10 range of Froude numbers. The results define a novel design criterion for hydraulic engineering practice. It is concluded, upon comparison with analogous results from extensive although seemingly incomplete literature, that the systematic experimentation described herein completes the information needed to characterize the statistical structure of pressure fields past hydraulic jumps.