Based on the theory analysis of the mechanism and sediment movement,the main effect factors to the maximum scour depth in concave bank were analyzed, the scour experiments under different conditions with analogy model of the bend channel were designed.
Based on the observation and analysis of flow structure, a formula to calculate the maximum scour depth is obtained by using single factor analysis dimensional analysis, regression and optimization with the help of a computer.
when the scouring amount for all river reaches is maximum,the average scour depth of the river bed of the Jingjiang river reach will be 2.0～5.3 m,with its channel storage increment of 1.3 billion m~3; and for Chenglingji reach,the average scour depth of the river bed will be 2.5 m,with its channel storage increment of about 0.85 billion m~3;
To solve turbid-water dissipation in mountain river, The factors on influence to scour depth in energy dissipation were analyzed in this paper under the circumstance of pebble river bed and bed load in turbid -water.
According to many model experiments, the paper analyzed the relations between scour depth in turbid-water and discharge per unit width、sediment concentration、sand fraction and the impact of tailwater depth and sediment discharge on scour pit depth in details, discussed the variation relationships between the ratio of turbid-water to clear-water and Froude numbers, selected a suitable formula of turbid jet-trajectory distance.
n the basis of analyzing the property of water jet in the water cushion of scour pit,a newformula for estimation of scour depth is proposed by considering the concepts both of energy dissipationand of jet diffusion.
Viewing from the local scour, Zhaogou and peiyu projects are with the most severe local scour,and analysis demonstrates that scour depth is not only related to flow velocity but also closely to the angle of flow to the Popectbeing scoured.
From model tests and hydraulic calculations about the submerged groins in the macro-tidal bore area of Qiantangjiang Estuary, the development mechanism of scour at the upstream side of submerge groins under the bore action is proposed. Then the relaIton between upstream side scour depth of groin and water depth before arriving of the bore, the bore height, the groin height and the groin shape is established.