Abstract：To solve the problem of riverbed stability trend,the riverbed stability criterion was proposed based on the minimum rate of energy dissipation, Reynolds averaging method and variational principle. The riverbed stability criterion was verified by comparing literature data and longitudinal section stability coefficient. The 21years′ hydrological data of 1972, 1973, 1975—1980, 1982, 1985, 1987, 1988, 1991—2000 for six reaches of the Yellow River downstream formed by seven hydrometric stations from Huayuankou to Lijin were used to analysis the riverbed stability of the Yellow River downstream. The results show that the stability of the Yellow River downstream riverbed is gradually reduced, and the most unstable sections are in Sunkou and Aikou with riverbank needing to be reinforced. The reduced stability is due to that the Yellow River is aboveground river formed by the gradual silting of hyperconcentrated flow sediment at midstream and downstream with raised riverbed.
2017, Vol. 38 
