Location
Madrid, Spain
Session
Session 4
Start Date
12-1-2022 12:50 PM
Description
One method for rehabilitating and modernizing embankment dams is the addition of a concrete overlay that protects the embankment and allows floods to pass safely over the dam. Roller compacted concrete is commonly used, which makes it practical to use a stepped construction that also enhances energy dissipation. Analysis of flow conditions over such structures requires computation of aerated flow and its effects on flow depth, training wall design, and energy dissipation. This paper describes Spillway Pro, an energy-based water surface profile calculation tool for smooth spillway chutes (Wahl et al. 2019), recently improved to also analyze stepped chutes. The tool is applicable to a wide range of chute slopes, including flatter slopes typical of embankment dam overlays and steeper slopes encountered on concrete gravity dams. An energy-based analysis allows Spillway Pro to be applied to situations differing from the idealized configurations covered by available empirical approaches, such as non-constant slopes, varying step heights, and converging chutes. Spillway Pro integrates water surface profile calculations, aerated flow effects, and cavitation analysis, which is potentially important for steeper slopes and large unit discharges. Simultaneous calculation of smooth and stepped-chute flow profiles enables rapid assessment of the energy dissipation benefits of steps, as well as a comparison of the aerated flow and cavitation issues for smooth vs. stepped chute alternatives.
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Included in
Hydraulic Computations for Stepped Concrete Overlays of Embankment Dams
Madrid, Spain
One method for rehabilitating and modernizing embankment dams is the addition of a concrete overlay that protects the embankment and allows floods to pass safely over the dam. Roller compacted concrete is commonly used, which makes it practical to use a stepped construction that also enhances energy dissipation. Analysis of flow conditions over such structures requires computation of aerated flow and its effects on flow depth, training wall design, and energy dissipation. This paper describes Spillway Pro, an energy-based water surface profile calculation tool for smooth spillway chutes (Wahl et al. 2019), recently improved to also analyze stepped chutes. The tool is applicable to a wide range of chute slopes, including flatter slopes typical of embankment dam overlays and steeper slopes encountered on concrete gravity dams. An energy-based analysis allows Spillway Pro to be applied to situations differing from the idealized configurations covered by available empirical approaches, such as non-constant slopes, varying step heights, and converging chutes. Spillway Pro integrates water surface profile calculations, aerated flow effects, and cavitation analysis, which is potentially important for steeper slopes and large unit discharges. Simultaneous calculation of smooth and stepped-chute flow profiles enables rapid assessment of the energy dissipation benefits of steps, as well as a comparison of the aerated flow and cavitation issues for smooth vs. stepped chute alternatives.