Energy Dissipation on Block Ramps
Publication: Journal of Hydraulic Engineering
Volume 132, Issue 1
Abstract
Block ramps are structures often used in river restoration projects. They generally ensure a stable streambed and produce high energy dissipation. This paper shows the results of an experimental investigation conducted at the Hydraulic Laboratory of the Univ. of Pisa, Pisa, Italy on ramps of different slopes characterized by different bed materials. Experiments have been carried out in three different rectangular channels, where block ramps with a slope varying between and have been tested. The results have been compared with the ones obtained for a smooth ramp, which can be considered as a limit case in which the diameter of the bed material tends to zero. The amount of energy loss of such structures is essentially a function of the relative submergence, the slope, and the ratio between the critical water depth and the length of the ramp. Viscous effects and air entertainment can be considered negligible in the experimental range. Tests were carried out to find the case of nonsubmerged ramp conditions.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 132 • Issue 1 • January 2006
Pages: 41 - 48
Copyright
© 2006 ASCE.
History
Received: Mar 2, 2004
Accepted: Mar 8, 2005
Published online: Jan 1, 2006
Published in print: Jan 2006
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