1D Bridges: Difference between revisions
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'''Example of a bridge that could be
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==Pier Losses==
Peir loss coefficients are treated as a direct energy (form) loss and can be derived from information in publications such as ''Hydraulics of Bridge Waterways'' ([http://www.ciccp.es/ImgWeb/Castilla%20y%20Leon/Documentaci%C3%B3n%20T%C3%A9cnica/Hydraulics%20of%20Bridge%20Waterways%20(1978).pdf FHA, 1978] or [https://austroads.com.au/publications/bridges/agbt08 AUSTROADS, 2019]).
Energy loss estimates from bridge piers or other obstructions, vertical or horizontal, that do not cause upstream controlled flow regimes like pressure flow, are dependent on the ratio of the obstruction's area relative to the gross area of the bridge opening, the type of piers (or piling in the case of pile bents) and the angularity of the piers with the direction of flood flow. The FHA (1978) guidance advises what form loss coefficient should be adopted based on these input parameters.
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<li>Calculate the ratio of the water area occupied by piers to the gross water area of the constriction (both based on the normal water surface) and the angularity of the piers. These inputs are used to calculate "J" in the FHA documentation.</li>
<li>Use the FHA (1978) ''Incremental Backwater Coefficient for Piers'' data to calculate Kp. This is the value which will be entered into TUFLOW as the form loss coefficient.<br>
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