Author(s): Zhenwen Ren
Linked Author(s): Zhenwen Ren
Keywords: No Keywords
Abstract: The study of river-bed variation in ice period is more difficult than that in period of unobstructed flow, due to the presence of ice jam, so that a scientific conclusion has not been reached yet. A series of hydrometric observations have been carried out in ice period in a 17-km stretch of the Yellow River from Longkou to Nanyuan ever since 1982. The main items of observations are as follows: river stage, discharge, air temperature, elevation of ice surface, thickness of ice cover, thickness of ice jam, elevation of river-bed, depth of water, velocity distribution in the cross-section, etc. To some extent, findings have been accomplished with respect to law of motion of ice jam and river bed variation in ice period, among others. It has been shown from data observed in several ice periods that the trends of river-bed variation in the entire ice period is correlated with the variation of ice jam under the ice cover. In other words, scouring is manifest as a result of increase in thickness of ice jam, and deposition with decrease in thickness of ice jam, the Fr-value of streamflow under the ice jam playing a decisive role. The empirical formula reads thus: [equation]
Year: 1988