Open AccessEffect of vertical velocity profile approximations on estimates of dam breach discharge using surface velocities
Author(s) -
Liu Jie,
Xiao Hong,
Lin Pengzhi,
Zhou Chuanxing,
Wang Wei
Publication year - 2021
Publication title -
journal of flood risk management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.049
H-Index - 36
ISSN - 1753-318X
DOI - 10.1111/jfr3.12709
Subject(s) - particle image velocimetry , geology , crest , surface (topology) , hydrology (agriculture) , water level , geotechnical engineering , mechanics , geomorphology , turbulence , geometry , mathematics , physics , optics , geography , cartography
In order to investigate the relationship between water surface velocity and breach hydrograph, a series of dam breach experiments with a generalised landslide dam were conducted in an open channel of 50 m × 4 m × 2 m. The large‐scale particle image velocimetry (LSPIV) technique was applied to measure the time history of water surface velocity during the dam breach process, and the hydrography was obtained by integrating the surface velocity along the water depth. The influence of different vertical velocity profile approximation and suspended sediment concentration on the peak breach discharge were analysed and discussed. The results showed that the water depth over the breach crest can be described as a function of water surface velocity using d ¯ t = k 2 2u ¯ surf 2 / k 1 g . A simple formula based on surface velocity and breach width for the estimation of breach discharge was further proposed and verified.